From 51cbe342779bdc4f043a1480c011075740f80635 Mon Sep 17 00:00:00 2001
From: Tammo van der Heide <vanderhe@uni-bremen.de>
Date: Thu, 15 Aug 2024 13:50:57 +0200
Subject: [PATCH] Parallelize (MPI, optional) two-center integration

---
 .github/workflows/build.yml                   |  48 ++++-
 CMakeLists.txt                                |  23 ++
 README.rst                                    |  27 ++-
 cmake/SkProgsUtils.cmake                      | 129 +++++++++++
 common/include/error.fypp                     |  21 ++
 common/lib/CMakeLists.txt                     |  16 +-
 common/lib/environment.F90                    | 121 +++++++++++
 common/lib/globalenv.F90                      | 194 +++++++++++++++++
 common/lib/mpienv.F90                         | 203 ++++++++++++++++++
 common/lib/mpifx.F90                          |  18 ++
 common/lib/schedule.F90                       |  65 ++++++
 config.cmake                                  |  15 +-
 external/mpifx/CMakeLists.txt                 |   8 +
 sktools/src/sktools/calculators/sktwocnt.py   |   2 +-
 sktwocnt/lib/CMakeLists.txt                   |  25 ++-
 sktwocnt/lib/gridorbital.f90                  |   2 +-
 sktwocnt/lib/{twocnt.f90 => twocnt.F90}       | 168 +++++++++++++--
 sktwocnt/prog/CMakeLists.txt                  |  16 +-
 sktwocnt/prog/cmdargs.f90                     |   6 +-
 sktwocnt/prog/input.f90                       |  23 +-
 sktwocnt/prog/{main.f90 => main.F90}          |  24 ++-
 sktwocnt/prog/output.f90                      |  16 +-
 test/prog/sktable/CMakeLists.txt              |   4 +-
 .../Non-Relativistic/Dynamic-conv/_C-C.skf    |  42 ++++
 .../Non-Relativistic/Dynamic-conv/config      |   1 +
 .../Non-Relativistic/Dynamic-conv/skdef.hsd   |  72 +++++++
 .../Non-Relativistic/Dynamic-noconv/_C-C.skf  |  48 +++++
 .../Non-Relativistic/Dynamic-noconv/config    |   1 +
 .../Non-Relativistic/Dynamic-noconv/skdef.hsd |  72 +++++++
 test/prog/sktable/bin/testwithworkdir         |  15 +-
 test/prog/sktable/tests                       |   2 +
 utils/export/skprogs-config.cmake.in          |  11 +
 utils/test/check_submodule_commits            | 112 ++++++++++
 33 files changed, 1486 insertions(+), 64 deletions(-)
 create mode 100644 common/lib/environment.F90
 create mode 100644 common/lib/globalenv.F90
 create mode 100644 common/lib/mpienv.F90
 create mode 100644 common/lib/mpifx.F90
 create mode 100644 common/lib/schedule.F90
 create mode 100644 external/mpifx/CMakeLists.txt
 rename sktwocnt/lib/{twocnt.f90 => twocnt.F90} (89%)
 rename sktwocnt/prog/{main.f90 => main.F90} (53%)
 create mode 100644 test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/_C-C.skf
 create mode 100644 test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/config
 create mode 100644 test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/skdef.hsd
 create mode 100644 test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/_C-C.skf
 create mode 100644 test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/config
 create mode 100644 test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/skdef.hsd
 create mode 100755 utils/test/check_submodule_commits

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 4b0d6f77..501fbe06 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -16,6 +16,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest]
+        mpi: [nompi, openmpi]
         config: [Debug]
         version: [13]
 
@@ -38,11 +39,31 @@ jobs:
           --slave /usr/bin/gfortran gfortran /usr/bin/gfortran-${{ matrix.version }} \
           --slave /usr/bin/gcov gcov /usr/bin/gcov-${{ matrix.version }}
 
+    - name: Enable MPI build
+      if: contains(matrix.mpi, 'openmpi') || contains(matrix.mpi, 'mpich')
+      run: echo "WITH_MPI=true" >> $GITHUB_ENV
+
+    - name: Disable MPI build
+      if: contains(matrix.mpi, 'nompi')
+      run: echo "WITH_MPI=false" >> $GITHUB_ENV
+
     - name: Set Compiler
       run: |
         echo "FC=gfortran" >> $GITHUB_ENV
         echo "CC=gcc" >> $GITHUB_ENV
 
+    - name: Install OpenMPI
+      if: contains(matrix.mpi, 'openmpi')
+      run: |
+        sudo apt-get update
+        sudo apt-get install libopenmpi-dev
+
+    - name: Install MPICH
+      if: contains(matrix.mpi, 'mpich')
+      run: |
+        sudo apt-get update
+        sudo apt-get install mpich
+
     - name: Compile and Install libXC
       run: |
         git clone https://gitlab.com/libxc/libxc.git
@@ -50,7 +71,7 @@ jobs:
         git checkout 6.2.2
         cmake -DCMAKE_INSTALL_PREFIX=${PWD}/${BUILD_DIR}/${INSTALL_DIR} -DENABLE_FORTRAN=True -B ${BUILD_DIR} .
         cd ${BUILD_DIR}
-        make -j 2
+        make -j2
         make install
         cd ../../
 
@@ -65,8 +86,10 @@ jobs:
         pip3 install cmake fypp numpy scipy
 
     - name: Configure build
-      run: |
-        cmake -B ${BUILD_DIR} -DCMAKE_INSTALL_PREFIX=${PWD}/${BUILD_DIR}/${INSTALL_DIR} -DCMAKE_BUILD_TYPE=Debug .
+      run: >-
+        cmake -B ${BUILD_DIR} -DWITH_MPI=${WITH_MPI}
+        -DCMAKE_INSTALL_PREFIX=${PWD}/${BUILD_DIR}/${INSTALL_DIR}
+        -DCMAKE_BUILD_TYPE=${{ matrix.config }} .
 
     - name: Build project
       run: cmake --build ${BUILD_DIR}
@@ -74,7 +97,19 @@ jobs:
     - name: Run regression tests
       run: |
         pushd ${BUILD_DIR}
-        ctest -j 2 --output-on-failure
+        ctest -j2 --output-on-failure
+        popd
+
+    - name: Configure build (TEST_MPI_PROCS=2)
+      if: contains(matrix.mpi, 'openmpi') || contains(matrix.mpi, 'mpich')
+      run: |
+        cmake -B ${BUILD_DIR} -DTEST_MPI_PROCS=2 .
+
+    - name: Run regression tests (TEST_MPI_PROCS=2)
+      if: contains(matrix.mpi, 'openmpi') || contains(matrix.mpi, 'mpich')
+      run: |
+        pushd ${BUILD_DIR}
+        ctest -j1 --output-on-failure
         popd
 
     - name: Install project
@@ -96,6 +131,7 @@ jobs:
       CMAKE_OPTIONS: >-
         -DCMAKE_BUILD_TYPE=${{ matrix.config }}
         -DFYPP_FLAGS='-DTRAVIS'
+        -DWITH_MPI=false
 
     steps:
     - name: Checkout code
@@ -128,7 +164,7 @@ jobs:
         git checkout 6.2.2
         cmake -DCMAKE_INSTALL_PREFIX=${PWD}/${BUILD_DIR}/${INSTALL_DIR} -DENABLE_FORTRAN=True -B ${BUILD_DIR} .
         cd ${BUILD_DIR}
-        make -j 2
+        make -j2
         make install
         cd ../../
 
@@ -156,7 +192,7 @@ jobs:
     - name: Run regression tests
       run: |
         pushd ${BUILD_DIR}
-        ctest -j 2 --output-on-failure
+        ctest -j2 --output-on-failure
         popd
 
     - name: Install project
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 11181e34..3cc6f9e5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -30,6 +30,16 @@ endif()
 
 find_package(Libxc QUIET)
 
+if(WITH_MPI)
+  find_package(MPI REQUIRED)
+  if(NOT MPI_FORTRAN_FOUND)
+    message(FATAL_ERROR "Compiler ${CMAKE_Fortran_COMPILER} is not MPI capable but is specified "
+      "for a WITH_MPI=TRUE build")
+  endif()
+  list(FILTER MPI_Fortran_COMPILE_OPTIONS EXCLUDE REGEX  "-fallow-argument-mismatch")
+  message(STATUS "MPI_Fortran_COMPILE_OPTIONS: ${MPI_Fortran_COMPILE_OPTIONS}")
+endif()
+
 if (Libxc_FOUND AND Libxc_VERSION VERSION_LESS "6.0.0")
   message(FATAL_ERROR "SkProgs requires libXC version >=6.0.0 to work properly.")
 endif()
@@ -72,6 +82,19 @@ set(FYPP_BUILD_FLAGS "${FYPP_FLAGS}" "--file-var-root=${CMAKE_SOURCE_DIR}"
 set(PYTHON_INTERPRETER "python3" CACHE STRING
   "Python interpreter to use for installing and test python components")
 
+############## External components (optional) #################
+
+# Note 1 : GIT_TAG hashes below must be updated with the utils/test/check_submodule_commits script!
+# Note 2 : GIT_REPOSITORY URLs should be to https// addresses for the CI pipelines to see them
+
+if(WITH_MPI)
+  set(MPIFX_GIT_REPOSITORY "https://github.com/dftbplus/mpifx.git")
+  set(MPIFX_GIT_TAG "aca7a212f68778aacb33ed33925d45f83dab91ca")  # do not change manually!
+  skprogs_config_hybrid_dependency(MpiFx MpiFx::MpiFx "${HYBRID_CONFIG_METHODS}" "QUIET"
+    external/mpifx "${exclude}" "${MPIFX_GIT_REPOSITORY}" "${MPIFX_GIT_TAG}")
+  list(APPEND PKG_CONFIG_REQUIRES mpifx)
+endif()
+
 #################### Add source components ####################
 
 add_subdirectory(common)
diff --git a/README.rst b/README.rst
index 2ce0e3e5..c5ac64eb 100644
--- a/README.rst
+++ b/README.rst
@@ -27,7 +27,9 @@ Prerequisites
 
 * LAPACK/BLAS libraries (or compatible equivalents)
 
-* libXC library with f03 interface (version >=6.0.0)
+* libXC library with f03 interface (>=6.0.0)
+
+* MpiFx (>=1.5, MPI-enabled build only)
 
 
 Obtaining via Conda
@@ -65,7 +67,11 @@ Follow the usual CMake build workflow:
   the install location (i.e. path stored in ``YOUR_SKPROGS_INSTALL_FOLDER``,
   e.g. ``$HOME/opt/skprogs``) and the build directory (e.g. ``_build``)::
 
-    FC=gfortran cmake -DCMAKE_INSTALL_PREFIX=YOUR_SKPROGS_INSTALL_FOLDER -B _build .
+    FC=gfortran cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=YOUR_SKPROGS_INSTALL_FOLDER -B _build .
+
+  An MPI enabled build is obtained by additionally setting ``-DWITH_MPI=1``
+  (default: ``-DWITH_MPI=0``). At the moment only the two-center integration
+  code ``sktwocnt`` is MPI parallelized and benefits from multiple processors.
 
   If libXC is installed in a non-standard location, you may need to specify
   either the ``CMAKE_PREFIX_PATH`` environment variable (if libXC was built with
@@ -86,6 +92,18 @@ Follow the usual CMake build workflow:
     ctest -j
     popd
 
+* If you want to test the MPI enabled binary with more than one MPI-process, you
+  should set the ``TEST_MPI_PROCS`` variable in ``config.cmake`` accordingly,
+  e.g.::
+
+    set(TEST_MPI_PROCS "2" CACHE STRING "Nr. of processes used for testing")
+
+  The ``TEST_MPI_PROCS`` cache variable can be updated or changed also after the
+  compilation by invoking CMake with the appropriate ``-D`` option, e.g.::
+
+    cmake -B _build -DTEST_MPI_PROCS=2 .
+    pushd _build; ctest; popd
+
 * If the tests were successful, install the package via ::
 
     cmake --install _build
@@ -177,6 +195,11 @@ follows:
 
     skgen -o slateratom -t sktwocnt sktable -d C,H,O C,H,O
 
+  For an MPI enabled binary, make sure to prepend any required information to
+  the two-center binary, e.g.::
+
+    skgen -o slateratom -t "mpirun -np 2 sktwocnt" sktable -d C C |& tee output
+
   The SK-files will be created in the current folder. See the help (e.g. ``skgen
   -h``) for additional options.
 
diff --git a/cmake/SkProgsUtils.cmake b/cmake/SkProgsUtils.cmake
index d5f85909..d9f5dfdf 100644
--- a/cmake/SkProgsUtils.cmake
+++ b/cmake/SkProgsUtils.cmake
@@ -50,6 +50,11 @@ endfunction()
 function (skprogs_add_fypp_defines fyppflags)
 
   set(_fyppflags "${${fyppflags}}")
+
+  if(WITH_MPI)
+    list(APPEND _fyppflags -DWITH_MPI)
+  endif()
+
   set(${fyppflags} ${_fyppflags} PARENT_SCOPE)
 
 endfunction()
@@ -195,6 +200,130 @@ macro(skprogs_setup_global_compiler_flags)
 endmacro()
 
 
+# Handles a hybrid dependency.
+#
+# Depending on the list items in the config_methods variable, it will try to:
+#
+# - checkout the source as a submodule within the origin sub-folder ("Submodule")
+# - find the package as external dependency ("Find")
+# - fetch the source from a git repository ("Fetch") into the build folder
+#
+# The methods are tried in the order of their appearance until success the first eligible one.
+#
+# The methods "Submodule" and "Fetch" would call the passed sub-directory with add_subdirectory()
+# passing two variables with the source and binary directory.
+#
+# Args:
+#     package [in]: Name of the dependency to look for.
+#     config_methods [in]: Config methods to try
+#     target [in]: Name of the target, which must be exported after the configuration.
+#     findpkgopts [in]: Options to pass to find_package()
+#     subdir [in]: Subdirectory with CMakeFiles.txt for integrating package source.
+#     subdiropts [in]: Options to pass to the add_subdir() command.
+#     git_repository [in]: Git repository to fetch the package from.
+#     git_tag [in]: Git tag to use when fetching the source.
+#
+# Variables:
+#     <UPPER_PACKAGE_NAME>_SOURCE_DIR, <UPPER_PACKAGE_NAME>_BINARY_DIR:
+#         Source and binary directories for the build (to pass to add_subdirectory())
+#
+macro(skprogs_config_hybrid_dependency package target config_methods findpkgopts subdir subdiropts
+    git_repository git_tag)
+
+  set(_allowed_methods "submodule;find;fetch;pkgconf")
+  string(TOLOWER "${package}" _package_lower)
+  string(TOUPPER "${package}" _package_upper)
+
+  foreach(_config_method IN ITEMS ${config_methods})
+
+    string(TOLOWER "${_config_method}" _config_lower)
+    if(NOT ${_config_lower} IN_LIST _allowed_methods)
+      message(FATAL_ERROR "${package}: Unknown configuration method '${_config_method}'")
+    endif()
+
+    if("${_config_lower}" STREQUAL "find")
+
+      message(STATUS "${package}: Trying to find installed package")
+      find_package(${package} ${findpkgopts})
+      if(${package}_FOUND)
+        message(STATUS "${package}: Installed package found")
+        break()
+      else()
+        message(STATUS "${package}: Installed package could not be found")
+      endif()
+
+    elseif("${_config_lower}" STREQUAL "pkgconf")
+      message(STATUS "${package}: Trying to find installed package (pkg-config)")
+
+      find_package(PkgConfig QUIET)
+      if(PkgConfig_FOUND)
+        pkg_check_modules("${_package_upper}" QUIET "${package}")
+        if("${${_package_upper}_FOUND}")
+          message(STATUS "${package}: Installed package found (pkg-config)")
+          add_library("${target}" INTERFACE IMPORTED)
+          target_link_libraries(
+            "${target}"
+            INTERFACE
+            "${${_package_upper}_LINK_LIBRARIES}"
+          )
+          target_include_directories(
+            "${target}"
+            INTERFACE
+            "${${_package_upper}_INCLUDE_DIRS}"
+          )
+          break()
+        else()
+          message(STATUS "${package}: Installed package could not be found (pkg-config)")
+        endif()
+      endif()
+
+    elseif("${_config_lower}" STREQUAL "submodule")
+
+      if (NOT EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${subdir}/origin/CMakeLists.txt
+          AND GIT_WORKING_COPY)
+        message(STATUS "${package}: Downloading via git submodule update")
+        execute_process(COMMAND ${GIT_EXECUTABLE} submodule update --init ${subdir}/origin
+          WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
+      endif()
+
+      if (EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/${subdir}/origin/CMakeLists.txt)
+        message(STATUS "${package}: Using source in ${subdir}/origin")
+        set(${_package_upper}_SOURCE_DIR "origin")
+        set(${_package_upper}_BINARY_DIR)
+        add_subdirectory(${subdir} ${subdiropts})
+        break()
+      endif()
+
+    elseif("${_config_lower}" STREQUAL "fetch")
+
+      message(STATUS "${package}: Fetching from repository ${git_repository}@${git_tag}")
+      FetchContent_Declare(${_package_lower} GIT_REPOSITORY ${git_repository} GIT_TAG ${git_tag})
+      FetchContent_GetProperties(${_package_lower})
+      if(NOT ${_package_lower}_POPULATED)
+        FetchContent_Populate(${_package_lower})
+      endif()
+      set(${_package_upper}_SOURCE_DIR "${${_package_lower}_SOURCE_DIR}")
+      set(${_package_upper}_BINARY_DIR "${${_package_lower}_BINARY_DIR}")
+      add_subdirectory(${subdir} ${subdiropts})
+      break()
+
+    endif()
+
+  endforeach()
+
+  if(NOT TARGET ${target})
+    message(FATAL_ERROR "Could not configure ${package} to export target '${target}'")
+  endif()
+
+  unset(_allowed_methods)
+  unset(_package_lower)
+  unset(_package_upper)
+  unset(_config_method)
+  unset(_config_lower)
+
+endmacro()
+
+
 # Checks whether the current compiler fullfills minimal version requirements.
 #
 #
diff --git a/common/include/error.fypp b/common/include/error.fypp
index cbd9d419..b474c16c 100644
--- a/common/include/error.fypp
+++ b/common/include/error.fypp
@@ -15,6 +15,27 @@
 #!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 
 
+#! Macro to return an error flag if return variable available or throw
+#! an error and shut down otherwise
+#:def ERROR_HANDLING(errVar, errNumber, msg)
+  block
+    use common_accuracy, only : lc
+    use common_message
+    !> Error handling string
+    character(lc) :: stringTmp
+
+    write(stringTmp,"(A)")${msg}$
+    if (present(${errVar}$)) then
+      ${errVar}$ = ${errNumber}$
+      call warning(stringTmp)
+      return
+    else
+      call error(stringTmp)
+    end if
+  end block
+#:enddef ERROR_HANDLING
+
+
 #! Propagation of error handling, for now it just returns when in error
 #:def HANDLE_ERROR(errVar)
   if (present(${errVar}$)) then
diff --git a/common/lib/CMakeLists.txt b/common/lib/CMakeLists.txt
index 7a3a653a..a245b89d 100644
--- a/common/lib/CMakeLists.txt
+++ b/common/lib/CMakeLists.txt
@@ -31,12 +31,26 @@ set(sources-f90
   utils.F90)
 
 set(sources-fpp
-  assert.F90)
+  assert.F90
+  environment.F90
+  globalenv.F90
+  mpifx.F90
+  schedule.F90)
+
+if(WITH_MPI)
+  list(APPEND sources-fpp
+    mpienv.F90)
+endif()
 
 skprogs_preprocess("${FYPP}" "${fypp_flags}" "F90" "f90" "${sources-fpp}" sources-f90-preproc)
 
 add_library(skprogs-common ${sources-f90} ${sources-f90-preproc})
 
+if(WITH_MPI)
+  target_link_libraries(skprogs-common MPI::MPI_Fortran)
+  target_link_libraries(skprogs-common MpiFx::MpiFx)
+endif()
+
 set(moddir ${CMAKE_CURRENT_BINARY_DIR}/modfiles)
 set_target_properties(skprogs-common PROPERTIES Fortran_MODULE_DIRECTORY ${moddir})
 target_include_directories(skprogs-common PUBLIC
diff --git a/common/lib/environment.F90 b/common/lib/environment.F90
new file mode 100644
index 00000000..6d2c7d56
--- /dev/null
+++ b/common/lib/environment.F90
@@ -0,0 +1,121 @@
+!--------------------------------------------------------------------------------------------------!
+!  DFTB+: general package for performing fast atomistic simulations                                !
+!  Copyright (C) 2006 - 2023  DFTB+ developers group                                               !
+!                                                                                                  !
+!  See the LICENSE file for terms of usage and distribution.                                       !
+!--------------------------------------------------------------------------------------------------!
+
+#:include 'common.fypp'
+#:include 'error.fypp'
+
+!> Contains computer environment settings
+module common_environment
+  use common_globalenv, only : shutdown, stdOut
+#:if WITH_MPI
+  use common_globalenv, only : globalMpiComm
+  use common_mpienv, only : TMpiEnv, TMpiEnv_init, TMpiEnv_final
+#:endif
+  implicit none
+
+  private
+  public :: TEnvironment, TEnvironment_init
+
+
+  !> Contains environment settings.
+  type :: TEnvironment
+    private
+
+    !> Whether this process is the lead?
+    logical, public :: tGlobalLead = .true.
+
+    !> Nr. of groups in the system
+    integer, public :: nGroup = 1
+
+    !> Id of current group (starts with 0)
+    integer, public :: myGroup = 0
+
+  #:if WITH_MPI
+    !> Global mpi settings
+    type(TMpiEnv), public :: mpi
+
+    !> Whether MPI environment had been initialised
+    logical :: mpiInitialised = .false.
+  #:endif
+
+  contains
+    procedure :: destruct => TEnvironment_destruct
+    procedure :: shutdown => TEnvironment_shutdown
+
+  #:if WITH_MPI
+    procedure :: initMpi => TEnvironment_initMpi
+  #:endif
+
+  end type TEnvironment
+
+
+contains
+
+  !> Returns an initialized instance.
+  subroutine TEnvironment_init(this)
+
+    !> Instance
+    type(TEnvironment), intent(out) :: this
+
+    continue
+
+  end subroutine TEnvironment_init
+
+
+  !> Finalizes the environment.
+  subroutine TEnvironment_destruct(this)
+
+    !> Instance
+    class(TEnvironment), intent(inout) :: this
+
+    #:if WITH_MPI
+      if (this%mpiInitialised) then
+        call TMpiEnv_final(this%mpi)
+        this%mpiInitialised = .false.
+      end if
+    #:endif
+
+    flush(stdOut)
+
+  end subroutine TEnvironment_destruct
+
+
+  !> Gracefully cleans up and shuts down.
+  !!
+  !! Note: This routine must be collectively called by all processes.
+  subroutine TEnvironment_shutdown(this)
+
+    !> Instance
+    class(TEnvironment), intent(inout) :: this
+
+    call this%destruct()
+    call shutdown()
+
+  end subroutine TEnvironment_shutdown
+
+
+#:if WITH_MPI
+  !> Initializes MPI environment.
+  subroutine TEnvironment_initMpi(this, nGroup)
+
+    !> Instance
+    class(TEnvironment), intent(inout) :: this
+
+    !> Number of process groups to create
+    integer, intent(in) :: nGroup
+
+    ! MPI settings
+    call TMpiEnv_init(this%mpi, globalMpiComm=globalMpiComm, nGroup=nGroup)
+    this%tGlobalLead = this%mpi%tGlobalLead
+    this%nGroup = this%mpi%nGroup
+    this%myGroup = this%mpi%myGroup
+    this%mpiInitialised = .true.
+
+  end subroutine TEnvironment_initMpi
+#:endif
+
+end module common_environment
diff --git a/common/lib/globalenv.F90 b/common/lib/globalenv.F90
new file mode 100644
index 00000000..e4aad0a0
--- /dev/null
+++ b/common/lib/globalenv.F90
@@ -0,0 +1,194 @@
+!--------------------------------------------------------------------------------------------------!
+!  DFTB+: general package for performing fast atomistic simulations                                !
+!  Copyright (C) 2006 - 2023  DFTB+ developers group                                               !
+!                                                                                                  !
+!  See the LICENSE file for terms of usage and distribution.                                       !
+!--------------------------------------------------------------------------------------------------!
+
+#:include 'common.fypp'
+
+!> Contains fundamental global computing environment settings.
+!!
+!! It contains global settings and routines, which can be used already before the parsing of the
+!! input has taken place and the details of the user settings for the running-environment are
+!! known. Also, it can be used by routines which are not MPI-aware but wish to make I/O or abort the
+!! code.
+module common_globalenv
+  use, intrinsic :: iso_fortran_env, only : output_unit, error_unit
+#:if WITH_MPI
+  use mpi, only : MPI_COMM_WORLD
+  use extlibs_mpifx, only : mpifx_comm, MPI_THREAD_FUNNELED, mpifx_init_thread, mpifx_abort,&
+      & mpifx_barrier, mpifx_finalize
+#:endif
+  implicit none
+
+  private
+  public :: initGlobalEnv, destructGlobalEnv
+  public :: abortProgram, shutdown, synchronizeAll
+  public :: stdOut, stdOut0, stdErr, stdErr0, tIoProc
+  public :: withMpi
+  #:if WITH_MPI
+    public :: globalMpiComm
+  #:endif
+
+
+  !> Unredirected standard out
+  integer, parameter :: stdOut0 = output_unit
+
+  !> Unredirected standard error
+  integer, parameter :: stdErr0 = error_unit
+
+  !> Standard out file handler
+  integer, protected :: stdOut = stdOut0
+
+  !> Standard error file handler
+  integer, protected :: stdErr = stdErr0
+
+  !> Whether current process is the global lead process
+  logical, protected :: tIoProc = .true.
+
+#:if WITH_MPI
+  !> Global MPI communicator (used for aborts)
+  type(mpifx_comm), protected :: globalMpiComm
+#:endif
+
+  !> Whether code was compiled with MPI support
+  logical, parameter :: withMpi = ${FORTRAN_LOGICAL(WITH_MPI)}$
+
+#:if WITH_MPI
+  !> Whether MPI finalization should be performed at the end
+  logical :: doMpiFinalization = .true.
+#:endif
+
+
+contains
+
+  !> Initializes global environment (must be the first statement of a program).
+  subroutine initGlobalEnv(outputUnit, mpiComm, errorUnit, devNull)
+
+    !> Customised global standard output
+    integer, intent(in), optional :: outputUnit
+
+    !> Customised global MPI communicator
+    integer, intent(in), optional :: mpiComm
+
+    !> Customised global standard error
+    integer, intent(in), optional :: errorUnit
+
+    !> Unit of the null device (needed for follow processes to suppress their output)
+    integer, intent(in), optional :: devNull
+
+    integer :: outputUnit0, errorUnit0, devNull0
+
+  #:if WITH_MPI
+    integer :: mpiComm0
+  #:endif
+
+    if (present(outputUnit)) then
+      outputUnit0 = outputUnit
+    else
+      outputUnit0 = stdOut0
+    end if
+
+    if (present(errorUnit)) then
+      errorUnit0 = errorUnit
+    else
+      errorUnit0 = stdErr0
+    end if
+
+  #:if WITH_MPI
+    if (present(mpiComm)) then
+      mpiComm0 = mpiComm
+      doMpiFinalization = .false.
+    else
+      mpiComm0 = MPI_COMM_WORLD
+      call mpifx_init_thread(requiredThreading=MPI_THREAD_FUNNELED)
+    end if
+
+    call globalMpiComm%init(commid=mpiComm0)
+    if (globalMpiComm%lead) then
+      stdOut = outputUnit0
+      stdErr = errorUnit0
+    else
+      if (present(devNull)) then
+        devNull0 = devNull
+      else
+        open(newunit=devNull0, file="/dev/null", action="write")
+      end if
+      stdOut = devNull0
+      stdErr = devNull0
+    end if
+    tIoProc = globalMpiComm%lead
+  #:else
+    stdOut = outputUnit0
+    stdErr = errorUnit0
+  #:endif
+
+  end subroutine initGlobalEnv
+
+
+  !> Finalizes global environment (must be the last statement of a program).
+  subroutine destructGlobalEnv()
+
+  #:if WITH_MPI
+    if (doMpiFinalization) then
+      call mpifx_finalize()
+    end if
+  #:endif
+
+  end subroutine destructGlobalEnv
+
+
+  !> Gracefully shuts down environment and stops execution.
+  !!
+  !! Note: this routine must be called collectively by all processes.
+  subroutine shutdown()
+
+    call synchronizeAll()
+    call destructGlobalEnv()
+    stop
+
+  end subroutine shutdown
+
+
+  !> Aborts program execution immediately.
+  !!
+  !! Note: if this routine is called by any the processes, execution immediately stops
+  !! without waiting for any other processes.
+  subroutine abortProgram(errorCode)
+
+    !> Error code to emit (default: 1)
+    integer, intent(in), optional :: errorCode
+
+    integer :: errorCode0
+  #:if WITH_MPI
+    integer :: error
+  #:endif
+
+    if (.not. present(errorCode)) then
+      errorCode0 = 1
+    else
+      errorCode0 = errorCode
+    end if
+
+  #:if WITH_MPI
+    call mpifx_abort(globalMpiComm, errorCode0, error)
+    if (error /= 0) then
+      write(stdErr0, "(A,I0,A)") "Process ", globalMpiComm%rank, " could not be aborted."
+    end if
+  #:endif
+    error stop
+
+  end subroutine abortProgram
+
+
+  !> Waits until all processes reach this point.
+  subroutine synchronizeAll()
+
+  #:if WITH_MPI
+    call mpifx_barrier(globalMpiComm)
+  #:endif
+
+  end subroutine synchronizeAll
+
+end module common_globalenv
diff --git a/common/lib/mpienv.F90 b/common/lib/mpienv.F90
new file mode 100644
index 00000000..ddab0589
--- /dev/null
+++ b/common/lib/mpienv.F90
@@ -0,0 +1,203 @@
+!--------------------------------------------------------------------------------------------------!
+!  DFTB+: general package for performing fast atomistic simulations                                !
+!  Copyright (C) 2006 - 2023  DFTB+ developers group                                               !
+!                                                                                                  !
+!  See the LICENSE file for terms of usage and distribution.                                       !
+!--------------------------------------------------------------------------------------------------!
+
+#:include "common.fypp"
+#:include "error.fypp"
+
+
+!> Contains MPI related environment settings
+module common_mpienv
+  use common_accuracy, only : lc
+  use extlibs_mpifx, only : mpifx_comm, mpifx_allgather, MPI_COMM_TYPE_SHARED
+  use common_message, only : error
+  implicit none
+
+  private
+  public :: TMpiEnv, TMpiEnv_init, TMpiEnv_final
+
+
+  !> Contains MPI related environment settings
+  type :: TMpiEnv
+
+    !> Global MPI communicator
+    type(mpifx_comm) :: globalComm
+
+    !> Communicator to access processes within current group
+    type(mpifx_comm) :: groupComm
+
+    !> Communicator to access equivalent processes in other groups
+    type(mpifx_comm) :: interGroupComm
+
+    !> Communicator within the current node
+    type(mpifx_comm) :: nodeComm
+
+    !> Size of the process groups
+    integer :: groupSize
+
+    !> Number of processor groups
+    integer :: nGroup
+
+    !> Group index of the current process (starts with 0)
+    integer :: myGroup
+
+    !> Rank of the processes in the given group (with respect of globalComm)
+    integer, allocatable :: groupMembersGlobal(:)
+
+    !> Rank of the processes in the given group (with respect of MPI_COMM_WORLD)
+    integer, allocatable :: groupMembersWorld(:)
+
+    !> Whether current process is the global lead
+    logical :: tGlobalLead
+
+    !> Whether current process is the group lead
+    logical :: tGroupLead
+
+  contains
+
+    procedure :: mpiSerialEnv
+
+  end type TMpiEnv
+
+
+contains
+
+  !> Initializes MPI environment.
+  ! ---------------------------------------------------------------
+  ! Initializes global communicator and group communicators
+  ! Example:
+  ! globalSize = 10
+  ! nGroup = 2
+  ! groupSize = 5
+  !                        rank
+  ! globalComm:      0 1 2 3 4 5 6 7 8 9
+  ! groupComm:       0 1 2 3 4 0 1 2 3 4
+  ! interGroupComm:  0 0 0 0 0 1 1 1 1 1
+  ! ---------------------------------------------------------------
+  ! SCALAPACK
+  ! Different groups handle different kpoints/spin (iKS)
+  ! All procs within a group know eigenval(:,iKS)
+  ! These are distributed to all other nodes using interGroupComm
+  ! eigenvec(:,:,iKS) are used to build the density matrix, DM(:,:,iKS)
+  ! DM(:,:,iKS) contains kWeight(iK) and occupation(iKS)
+  ! total DM(:,:) is obtained by mpiallreduce with MPI_SUM
+  ! ---------------------------------------------------------------
+  ! LIBNEGF
+  ! Different groups handle different kpoints/spin (iKS)
+  ! All procs within a group know densMat(:,:,iKS)
+  ! DM(:,:,iKS) contains kWeight(iK) and occupation(iKS)
+  ! total DM(:,:) is obtained by mpiallreduce with MPI_SUM
+  ! ---------------------------------------------------------------
+  subroutine TMpiEnv_init(this, globalMpiComm, nGroup)
+
+    !> Initialised instance on exit
+    type(TMpiEnv), intent(out) :: this
+
+    !> The global MPI communicator (assumed to be MPI_COMM_WORLD if not specified)
+    type(mpifx_comm), optional, intent(in) :: globalMpiComm
+
+    !> Number of process groups to create
+    integer, intent(in), optional :: nGroup
+
+    if (present(globalMpiComm)) then
+      this%globalComm = globalMpiComm
+    else
+      call this%globalComm%init()
+    end if
+    if (present(nGroup)) then
+      this%nGroup = nGroup
+    else
+      this%nGroup = 1
+    end if
+
+    call setup_inter_node_communicator(this)
+    call setup_subgrids_common(this)
+
+    this%tGlobalLead = this%globalComm%lead
+    this%tGroupLead = this%groupComm%lead
+
+    if (this%tGlobalLead .and. .not. this%tGroupLead) then
+      call error("Internal error: Global lead process is not a group leading process")
+    end if
+
+  end subroutine TMpiEnv_init
+
+
+  !> Finalises the communicators in the structure supplied here
+  subroutine TMpiEnv_final(this)
+
+    !> Initialised instance
+    type(TMpiEnv), intent(inout) :: this
+
+    call this%interGroupComm%free()
+    call this%groupComm%free()
+
+  end subroutine TMpiEnv_final
+
+
+  !> Routine to check this is a single processor instance, stopping otherwise (useful to call in
+  !! purely serial codes to avid multiple copies being invoked with mpirun)
+  subroutine mpiSerialEnv(this, iErr)
+
+    !> Instance
+    class(TMpiEnv), intent(in) :: this
+
+    !> Optional error flag
+    integer, intent(out), optional :: iErr
+
+    if (this%globalComm%size > 1) then
+      @:ERROR_HANDLING(iErr, -1, 'This is serial code, but invoked on multiple processors')
+    end if
+
+  end subroutine mpiSerialEnv
+
+
+  !> Sets up subgrids and group communicators used with common (non-NEGF) solvers.
+  subroutine setup_subgrids_common(this)
+
+    !> Environment instance
+    type(TMpiEnv), intent(inout) :: this
+
+    integer :: myRank, myGroup
+    character(lc) :: tmpStr
+    type(mpifx_comm) :: mpiCommWorld
+
+    this%groupSize = this%globalComm%size / this%nGroup
+    if (this%nGroup * this%groupSize /= this%globalComm%size) then
+      write(tmpStr, "(A,I0,A,I0,A)") "Number of groups (", this%nGroup,&
+          & ") not compatible with number of processes (", this%globalComm%size, ")"
+      call error(tmpStr)
+    end if
+
+    this%myGroup = this%globalComm%rank / this%groupSize
+    myRank = mod(this%globalComm%rank, this%groupSize)
+    call this%globalComm%split(this%myGroup, myRank, this%groupComm)
+    allocate(this%groupMembersGlobal(this%groupSize))
+    call mpifx_allgather(this%groupComm, this%globalComm%rank, this%groupMembersGlobal)
+
+    ! Make a wrapper around MPI_COMM_WORLD and get group member ids within that descriptor
+    call mpiCommWorld%init()
+    allocate(this%groupMembersWorld(this%groupSize))
+    call mpifx_allgather(this%groupComm, mpiCommWorld%rank, this%groupMembersWorld)
+
+    myGroup = myRank
+    myRank = this%myGroup
+    call this%globalComm%split(myGroup, myRank, this%interGroupComm)
+
+  end subroutine setup_subgrids_common
+
+
+  !> Sets up a communicator within the node to use MPI shared memory.
+  subroutine setup_inter_node_communicator(this)
+
+    !> Environment instance
+    type(TMpiEnv), intent(inout) :: this
+
+    call this%globalComm%split_type(MPI_COMM_TYPE_SHARED, this%globalComm%rank, this%nodeComm)
+
+  end subroutine setup_inter_node_communicator
+
+end module common_mpienv
diff --git a/common/lib/mpifx.F90 b/common/lib/mpifx.F90
new file mode 100644
index 00000000..78b7dda9
--- /dev/null
+++ b/common/lib/mpifx.F90
@@ -0,0 +1,18 @@
+!--------------------------------------------------------------------------------------------------!
+!  DFTB+: general package for performing fast atomistic simulations                                !
+!  Copyright (C) 2006 - 2023  DFTB+ developers group                                               !
+!                                                                                                  !
+!  See the LICENSE file for terms of usage and distribution.                                       !
+!--------------------------------------------------------------------------------------------------!
+
+#:include 'common.fypp'
+
+!> Exporting mpifx functionality if compiled with mpi support, otherwise empty.
+module extlibs_mpifx
+#:if WITH_MPI
+  use libmpifx_module
+#:endif
+  implicit none
+  public
+
+end module extlibs_mpifx
diff --git a/common/lib/schedule.F90 b/common/lib/schedule.F90
new file mode 100644
index 00000000..b1d08f4a
--- /dev/null
+++ b/common/lib/schedule.F90
@@ -0,0 +1,65 @@
+!--------------------------------------------------------------------------------------------------!
+!  DFTB+: general package for performing fast atomistic simulations                                !
+!  Copyright (C) 2006 - 2023  DFTB+ developers group                                               !
+!                                                                                                  !
+!  See the LICENSE file for terms of usage and distribution.                                       !
+!--------------------------------------------------------------------------------------------------!
+
+#:include 'common.fypp'
+
+!> Contains routines helpful for MPI-parallelisation.
+module common_schedule
+  use common_environment, only : TEnvironment
+  implicit none
+
+  private
+  public :: getStartAndEndIndex
+
+
+contains
+
+  !> Returns the start and end index of an MPI process that calculates parts of a loop.
+  subroutine getStartAndEndIndex(env, nElements, iStart, iEnd)
+
+    !> Environment settings
+    type(TEnvironment), intent(in) :: env
+
+    !> Array size to split
+    integer, intent(in) :: nElements
+
+    !> Start and end index of current element range
+    integer, intent(out) :: iStart, iEnd
+
+  #:if WITH_MPI
+    !! Size of split index regions
+    integer :: splitSize
+
+    !! Number of elements that exceed integer times nProcs
+    integer :: offset
+  #:endif
+
+    @:ASSERT(nElements >= 0)
+
+  #:if WITH_MPI
+    @:ASSERT(env%mpi%globalComm%rank < env%mpi%globalComm%size)
+
+    splitSize = nElements / env%mpi%globalComm%size
+
+    ! start and end indices assuming equal split sizes
+    iStart = env%mpi%globalComm%rank * splitSize + 1
+    iEnd = iStart + splitSize - 1
+
+    ! distribute possible remainder to the ranges at the end
+    offset = env%mpi%globalComm%size - mod(nElements, env%mpi%globalComm%size)
+    if (env%mpi%globalComm%rank + 1 > offset) then
+      iStart = iStart + env%mpi%globalComm%rank - offset
+      iEnd = iEnd + env%mpi%globalComm%rank - offset + 1
+    end if
+  #:else
+    iStart = 1
+    iEnd = nElements
+  #:endif
+
+  end subroutine getStartAndEndIndex
+
+end module common_schedule
diff --git a/config.cmake b/config.cmake
index a34d68b9..b78abcde 100644
--- a/config.cmake
+++ b/config.cmake
@@ -7,10 +7,20 @@
 # automatically default to RelWithDebInfo if used in a single configuration build. Uncomment or
 # override it only if you want a non-default single configuration build.
 
+option(WITH_MPI "Whether SkProgs should support MPI-parallelism" FALSE)
+
 #
 # Test environment settings
 #
-set(TEST_RUNNER_TEMPLATE " " CACHE STRING "How to run the tests")
+set(TEST_MPI_PROCS "1" CACHE STRING "Nr. of MPI processes used for testing")
+
+# Command line used to launch the test code.
+# The escaped variables (\${VARIABLE}) will be substituted by the corresponding CMake variables.
+if(WITH_MPI)
+  set(TEST_RUNNER_TEMPLATE "mpiexec -n \${TEST_MPI_PROCS}" CACHE STRING "How to run the tests")
+else()
+  set(TEST_RUNNER_TEMPLATE " " CACHE STRING "How to run the tests")
+endif()
 
 #
 # Installation options
@@ -32,3 +42,6 @@ set(INSTALL_MODULEDIR "${INSTALL_INCLUDEDIR}/modfiles" CACHE PATH
 #set(TOOLCHAIN "gnu" CACHE STRING "Prefix of the toolchain file to be read from the sys/ folder")
 # Uncomment and set it if you want to override the automatic, compiler based toolchain file
 # selection.
+
+set(HYBRID_CONFIG_METHODS "Submodule;Find;Fetch" CACHE STRING
+  "Configuration methods to try in order to satisfy hybrid dependencies")
diff --git a/external/mpifx/CMakeLists.txt b/external/mpifx/CMakeLists.txt
new file mode 100644
index 00000000..f06f5b47
--- /dev/null
+++ b/external/mpifx/CMakeLists.txt
@@ -0,0 +1,8 @@
+# This CMakeLists.txt should be invoked via skprogs_config_hybrid_dependency()!
+
+set(BUILD_EXPORTED_TARGETS_ONLY TRUE)
+
+add_subdirectory(${MPIFX_SOURCE_DIR} ${MPIFX_BINARY_DIR})
+
+add_library(MpiFx::MpiFx INTERFACE IMPORTED GLOBAL)
+target_link_libraries(MpiFx::MpiFx INTERFACE MpiFx)
diff --git a/sktools/src/sktools/calculators/sktwocnt.py b/sktools/src/sktools/calculators/sktwocnt.py
index c58a56aa..7ee5eeb7 100644
--- a/sktools/src/sktools/calculators/sktwocnt.py
+++ b/sktools/src/sktools/calculators/sktwocnt.py
@@ -278,7 +278,7 @@ def __init__(self, binary, workdir):
     def run(self):
         fpin = open(os.path.join(self._workdir, INPUT_FILE), "r")
         fpout = open(os.path.join(self._workdir, STDOUT_FILE), "w")
-        proc = subproc.Popen([self._binary], cwd=self._workdir,
+        proc = subproc.Popen(self._binary.split(), cwd=self._workdir,
                              stdin=fpin, stdout=fpout, stderr=subproc.STDOUT)
         proc.wait()
         fpin.close()
diff --git a/sktwocnt/lib/CMakeLists.txt b/sktwocnt/lib/CMakeLists.txt
index 779ef7c0..8b13ef03 100644
--- a/sktwocnt/lib/CMakeLists.txt
+++ b/sktwocnt/lib/CMakeLists.txt
@@ -1,16 +1,33 @@
+set(projectdir ${PROJECT_SOURCE_DIR})
+
+#
+# General options for all targets
+#
+set(fypp_flags ${FYPP_BUILD_FLAGS} ${FYPP_CONFIG_FLAGS})
+list(APPEND fypp_flags -I${projectdir}/common/include -DRELEASE="'${RELEASE}'")
+
 set(sources-f90
   bisection.f90
   gridorbital.f90
   quadrature.f90
-  twocnt.f90
   xcfunctionals.f90)
 
-add_library(skprogs-sktwocnt ${sources-f90})
+set(sources-fpp
+  twocnt.F90)
+
+skprogs_preprocess("${FYPP}" "${fypp_flags}" "F90" "f90" "${sources-fpp}" sources-f90-preproc)
+
+add_library(skprogs-sktwocnt ${sources-f90} ${sources-f90-preproc})
 
 target_link_libraries(skprogs-sktwocnt skprogs-common)
 
-target_link_libraries(skprogs-sktwocnt skprogs-common Libxc::xcf03 Libxc::xc)
-target_link_libraries(skprogs-sktwocnt skprogs-common LAPACK::LAPACK)
+target_link_libraries(skprogs-sktwocnt Libxc::xcf03 Libxc::xc)
+target_link_libraries(skprogs-sktwocnt LAPACK::LAPACK)
+
+if(WITH_MPI)
+  target_link_libraries(skprogs-sktwocnt MPI::MPI_Fortran)
+  target_link_libraries(skprogs-sktwocnt MpiFx::MpiFx)
+endif()
 
 set(moddir ${CMAKE_CURRENT_BINARY_DIR}/modfiles)
 set_target_properties(skprogs-sktwocnt PROPERTIES Fortran_MODULE_DIRECTORY ${moddir})
diff --git a/sktwocnt/lib/gridorbital.f90 b/sktwocnt/lib/gridorbital.f90
index 06cb594c..717f5c14 100644
--- a/sktwocnt/lib/gridorbital.f90
+++ b/sktwocnt/lib/gridorbital.f90
@@ -128,7 +128,7 @@ elemental function TGridorb1_getValue(this, rr) result(rad)
 
     ! sanity check
     ! if (this%nGrid < ninter + 1) then
-    !   write(*,*) "Not enough points in the orbital grid!"
+    !   write(stdOut,*) "Not enough points in the orbital grid!"
     !   stop
     ! end if
 
diff --git a/sktwocnt/lib/twocnt.f90 b/sktwocnt/lib/twocnt.F90
similarity index 89%
rename from sktwocnt/lib/twocnt.f90
rename to sktwocnt/lib/twocnt.F90
index 9c63bf24..61119113 100644
--- a/sktwocnt/lib/twocnt.f90
+++ b/sktwocnt/lib/twocnt.F90
@@ -1,8 +1,12 @@
+#:include 'common.fypp'
+
 !> Module that contains the two-center integrator routines for tabulating Hamiltonian and overlap.
 module twocnt
 
   use common_accuracy, only : dp
   use common_constants, only : pi, rec4pi
+  use common_globalenv, only : stdOut
+  use common_environment, only : TEnvironment
   use common_anglib, only : initGaunt, freeGaunt, realGaunt
   use common_coordtrans, only : coordtrans_becke_12, coordtrans_radial_becke2
   use common_sphericalharmonics, only : TRealTessY, TRealTessY_init
@@ -11,11 +15,16 @@ module twocnt
   use common_partition, only : partition_becke_homo
   use common_splines, only : spline3ders
   use common_fifo, only : TFiFoReal2
+  use common_schedule, only : getStartAndEndIndex
   use common_interpolation, only : get2ndNaturalSplineDerivs, get_cubic_spline
   use common_poisson, only : solvePoisson, TBeckeGridParams, TBeckeIntegrator,&
       & TBeckeIntegrator_init, TBeckeIntegrator_setKernelParam, TBeckeIntegrator_precompFdMatrix,&
       & TBeckeIntegrator_buildLU, TBeckeIntegrator_getCoords, TBeckeIntegrator_solveHelmholz
 
+#:if WITH_MPI
+  use extlibs_mpifx, only : MPI_SUM, MPI_MAX, mpifx_allreduceip
+#:endif
+
   use gridorbital, only : TGridorb2
   use xcfunctionals, only : xcFunctional
 
@@ -152,7 +161,10 @@ module twocnt
 contains
 
   !> Calculates Hamiltonian and overlap matrix elements for different dimer distances.
-  subroutine get_twocenter_integrals(inp, imap, skham, skover)
+  subroutine get_twocenter_integrals(env, inp, imap, skham, skover)
+
+    !> Environment settings
+    type(TEnvironment), intent(in) :: env
 
     !> parsed twocnt input instance
     type(TTwocntInp), intent(in), target :: inp
@@ -229,6 +241,18 @@ subroutine get_twocenter_integrals(inp, imap, skham, skover)
     !! number of radial and angular integration abscissas
     integer :: nRad, nAng
 
+    !! start and end index for MPI parallelization, if applicable
+    integer :: iParallelStart, iParallelEnd
+
+    !! number of distances that fit inside a batch of length 1 Bohr
+    integer :: nDistPer1Bohr
+
+    !! number of MPI ranks SkTwocnt was executed with and rank of this instance
+    integer :: nProcs, rank
+
+    !! true, if the number of MPI ranks exceeds the number of distances of a 1 Bohr batch
+    logical :: tCoresExceedBatch
+
     select case (inp%iXC)
     case(xcFunctional%LDA_PW91)
       call xc_f03_func_init(xcfunc_x, XC_LDA_X, XC_UNPOLARIZED)
@@ -320,27 +344,48 @@ subroutine get_twocenter_integrals(inp, imap, skham, skover)
 
     call TIntegMap_init(imap, atom1, atom2)
 
-    ! calculate lines for 1 Bohr in one batch.
+  #:if WITH_MPI
+    nProcs = env%mpi%globalComm%size
+    rank = env%mpi%globalComm%rank
+  #:else
+    nProcs = 1
+    rank = 0
+  #:endif
+
     dist = 0.0_dp
     tDynlen = (inp%maxdist > 0.0_dp)
+    ! calculate lines for 1 Bohr in one batch
+    nDistPer1Bohr = ceiling(1.0_dp / inp%dr)
+    tCoresExceedBatch = (nDistPer1Bohr < nProcs)
+
     if (tDynlen) then
-      nBatchline = ceiling(1.0_dp / inp%dr)
-      maxdist = inp%maxdist + real(nBatchline, dp) * inp%dr
+      if (tCoresExceedBatch) then
+        ! We do not want cores to idle around, therefore increase the batch size if the number of
+        ! MPI ranks exceeds the number of distances of the default batch length of 1 Bohr. An
+        ! increased batch size later requires the Hamiltonian and overlap data to be cropped to the
+        ! same size one would have obtained with the default batch length of 1 Bohr.
+        nBatchline = nProcs
+      else
+        nBatchline = nDistPer1Bohr
+      end if
+      maxdist = inp%maxdist + real(nDistPer1Bohr, dp) * inp%dr
     else
       maxdist = abs(inp%maxdist)
       nBatchline = ceiling((maxdist - inp%r0) / inp%dr)
     end if
     nBatch = 0
     denserrmax = 0.0_dp
-    allocate(denserr(nBatchline))
+    allocate(denserr(nBatchline), source=0.0_dp)
+    call getStartAndEndIndex(env, nBatchline, iParallelStart, iParallelEnd)
     lpBatch: do
-      allocate(skhambuffer(imap%ninteg, nBatchline))
-      allocate(skoverbuffer(imap%ninteg, nBatchline))
-      write(*, "(A,I0,A,F6.3,A,F6.3)") "Calculating ", nBatchline, " lines: r0 = ",&
+      allocate(skhambuffer(imap%ninteg, nBatchline), source=0.0_dp)
+      allocate(skoverbuffer(imap%ninteg, nBatchline), source=0.0_dp)
+      write(stdOut, "(A,I0,A,F6.3,A,F6.3)") "Calculating ", nBatchline, " lines: r0 = ",&
           & inp%r0 + inp%dr * real(nBatch * nBatchline, dp), " dr = ", inp%dr
-      lpDist: do ir = 1, nBatchline
+      denserr(:) = 0.0_dp
+      lpDist: do ir = iParallelStart, iParallelEnd
         dist = inp%r0 + inp%dr * real(nBatch * nBatchline + ir - 1, dp)
-        write(*, "(A,F6.2,A)") 'Calculating dimer distance: ', dist, ' Bohr'
+        write(*, "(A,F6.2,A,1I0)") 'Calculating dimer distance: ', dist, ' Bohr, on rank ', rank
         call gengrid2_2(quads, coordtrans_becke_12, partition_becke_homo, beckepars, dist, grid1,&
             & grid2, dots, weights)
         nRad = size(quads(1)%xx)
@@ -350,33 +395,51 @@ subroutine get_twocenter_integrals(inp, imap, skham, skover)
             & inp%camBeta, inp%tGlobalHybrid, inp%tLC, inp%tCam, imap, xcfunc_xc, xcfunc_x,&
             & xcfunc_xsr, xcfunc_c, skhambuffer(:, ir), skoverbuffer(:, ir), denserr(ir))
       end do lpDist
+    #:if WITH_MPI
+      call mpifx_allreduceip(env%mpi%globalComm, dist, MPI_MAX)
+      call mpifx_allreduceip(env%mpi%globalComm, denserr, MPI_SUM)
+      call mpifx_allreduceip(env%mpi%globalComm, skhambuffer, MPI_SUM)
+      call mpifx_allreduceip(env%mpi%globalComm, skoverbuffer, MPI_SUM)
+    #:endif
       denserrmax = max(denserrmax, maxval(denserr))
       maxabs = max(maxval(abs(skhambuffer)), maxval(abs(skoverbuffer)))
       if (tDynlen) then
         tConverged = (maxabs < inp%epsilon)
         ! if new batch gave no contributions above tolerance: omit it and exit
-        if (tConverged .or. dist > maxdist) exit
-        nBatch = nBatch + 1
+        if (tConverged .or. dist > maxdist) then
+          if (tCoresExceedBatch) then
+            ! If the number of cores lead to an increased batch size, we have to store the last
+            ! batch to be later able to crop the data to agree with the default batch size.
+            call hamfifo%push_alloc(skhambuffer)
+            call overfifo%push_alloc(skoverbuffer)
+          end if
+          exit lpBatch
+        end if
         call hamfifo%push_alloc(skhambuffer)
         call overfifo%push_alloc(skoverbuffer)
+        nBatch = nBatch + 1
       else
         tConverged = .true.
         call hamfifo%push_alloc(skhambuffer)
         call overfifo%push_alloc(skoverbuffer)
-        exit
+        exit lpBatch
       end if
     end do lpBatch
 
-    if (.not. tConverged) then
-      write(*, "(A,F6.2,A,ES10.3)") "Warning, maximal distance ", inp%maxdist,&
-          & " reached! Max integral value:", maxabs
-    end if
-    write(*, "(A,ES10.3)") "Maximal integration error: ", denserrmax
-
     ! hand over Hamiltonian and overlap
     call hamfifo%popall_concat(skham)
     call overfifo%popall_concat(skover)
 
+    if (tDynlen .and. tCoresExceedBatch) then
+      call cropData(inp, tConverged, nDistPer1Bohr, maxdist, skham, skover)
+    end if
+
+    if (.not. tConverged) then
+      write(stdOut, "(A,F6.2,A,ES10.3)") "Warning, maximal distance ", inp%maxdist,&
+          & " reached! Max integral value:", maxabs
+    end if
+    write(stdOut, "(A,ES10.3)") "Maximal integration error: ", denserrmax
+
     ! finalize libxc objects
     if (inp%tGlobalHybrid .or. inp%tCam) then
       if (inp%iXC == xcFunctional%CAMY_PBEh) then
@@ -697,6 +760,70 @@ subroutine getskintegrals(beckeInt, radialHFQuadrature, nRad, nAng, atom1, atom2
   end subroutine getskintegrals
 
 
+  !> Crops the Hamiltonian (H) and overlap (S) matrices to the number of distances one would have
+  !! obtained with the default 1 Bohr batch length.
+  subroutine cropData(inp, tConverged, nDistPer1Bohr, maxdist, skham, skover)
+
+    !> twocnt input instance
+    type(TTwocntInp), intent(in) :: inp
+
+    !> true, if the Hamiltonian and overlap matrix elements are converged
+    logical, intent(in) :: tConverged
+
+    !> maximum dimer distance to tabulate
+    real(dp), intent(in) :: maxdist
+
+    !> Hamiltonian and overlap matrices to crop
+    real(dp), intent(inout), allocatable :: skham(:,:), skover(:,:)
+
+    !! number of distances that fit inside a batch of length 1 Bohr
+    integer :: nDistPer1Bohr
+
+    !! number of full 1 Bohr batches that H and S have been tabulated for
+    integer :: nBatchInTot
+
+    !! iterates over 1 Bohr batches
+    integer :: iSmallBatch
+
+    !! start and end index of the current 1 Bohr batch
+    integer :: iSmallBatchStart, iSmallBatchEnd
+
+    !! maximum absolute of H and S matrix elements in current 1 Bohr batch
+    integer :: maxabs
+
+    !! end index when cropping H and S
+    integer :: iEnd
+
+    !! number of 1 Bohr batches within the maximum distance
+    integer :: nBatch
+
+    nDistPer1Bohr = ceiling(1.0_dp / inp%dr)
+
+    if (tConverged) then
+      ! crop to full 1 Bohr batches (converged version)
+      nBatchInTot = floor(real(size(skham, dim=2), dp) / real(nDistPer1Bohr, dp))
+      do iSmallBatch = 1, nBatchInTot
+        iSmallBatchStart = (iSmallBatch - 1) * nDistPer1Bohr + 1
+        iSmallBatchEnd = iSmallBatch * nDistPer1Bohr
+        maxabs = max(maxval(abs(skham(:, iSmallBatchStart:iSmallBatchEnd))),&
+            & maxval(abs(skover(:, iSmallBatchStart:iSmallBatchEnd))))
+        if (maxabs < inp%epsilon) then
+          iEnd = max(iSmallBatch - 1, 1) * nDistPer1Bohr
+          skham = skham(:, 1:iEnd)
+          skover = skover(:, 1:iEnd)
+          exit
+        end if
+      end do
+    else
+      ! crop to full 1 Bohr batches (max. distance reached version)
+      nBatch = ceiling(((maxdist - inp%r0) / inp%dr + 1.0_dp) / real(nDistPer1Bohr, dp) - 1.0_dp)
+      skham = skham(:, 1:nBatch * nDistPer1Bohr)
+      skover = skover(:, 1:nBatch * nDistPer1Bohr)
+    end if
+
+  end subroutine cropData
+
+
   !> Calculates libXC renormalized density superposition of dimer.
   pure function getLibxcRho(rho) result(rhor)
 
@@ -797,7 +924,8 @@ subroutine getDivergence(nRad, nAng, drho1, drho2, r1, r2, theta1, theta2, vsigm
     tval = aa(1, :)
 
     if ((rval(2) < rval(1)) .or. (tval(2) > tval(1))) then
-      write(*,*) 'getDivergence: Expected ascending order in radii and descending order in theta!'
+      write(stdOut,*) 'getDivergence: Expected ascending order in radii and descending order in&
+          & theta!'
       stop
     end if
 
diff --git a/sktwocnt/prog/CMakeLists.txt b/sktwocnt/prog/CMakeLists.txt
index 624afac7..395d62e2 100644
--- a/sktwocnt/prog/CMakeLists.txt
+++ b/sktwocnt/prog/CMakeLists.txt
@@ -1,10 +1,22 @@
+set(projectdir ${PROJECT_SOURCE_DIR})
+
+#
+# General options for all targets
+#
+set(fypp_flags ${FYPP_BUILD_FLAGS} ${FYPP_CONFIG_FLAGS})
+list(APPEND fypp_flags -I${projectdir}/common/include -DRELEASE="'${RELEASE}'")
+
 set(sources-f90
   cmdargs.f90
   input.f90
-  main.f90
   output.f90)
 
-add_executable(sktwocnt ${sources-f90})
+set(sources-fpp
+  main.F90)
+
+skprogs_preprocess("${FYPP}" "${fypp_flags}" "F90" "f90" "${sources-fpp}" sources-f90-preproc)
+
+add_executable(sktwocnt ${sources-f90} ${sources-f90-preproc})
 
 target_link_libraries(skprogs-sktwocnt skprogs-common Libxc::xcf03 Libxc::xc)
 target_link_libraries(sktwocnt skprogs-sktwocnt)
diff --git a/sktwocnt/prog/cmdargs.f90 b/sktwocnt/prog/cmdargs.f90
index 689a41b0..2cee0df5 100644
--- a/sktwocnt/prog/cmdargs.f90
+++ b/sktwocnt/prog/cmdargs.f90
@@ -1,6 +1,8 @@
 !> Module that handles command line argument parsing.
 module cmdargs
 
+  use common_globalenv, only : stdOut
+
   implicit none
   private
 
@@ -28,10 +30,10 @@ subroutine parse_command_arguments()
       call get_command_argument(1, arg)
       select case (arg)
       case ('--version')
-        write(*, '(A,1X,A)') programName, programVersion
+        write(stdOut, '(A,1X,A)') programName, programVersion
         stop
       case default
-        write(*, '(A,A,A)') "Invalid command line argument '", arg, "'"
+        write(stdOut, '(A,A,A)') "Invalid command line argument '", arg, "'"
         error stop
       end select
     end if
diff --git a/sktwocnt/prog/input.f90 b/sktwocnt/prog/input.f90
index 85515dde..b1a9cf1f 100644
--- a/sktwocnt/prog/input.f90
+++ b/sktwocnt/prog/input.f90
@@ -2,6 +2,7 @@
 module input
 
   use common_accuracy, only : dp
+  use common_globalenv, only : stdOut
   use gridorbital, only : TGridorb2_init
   use twocnt, only : TTwocntInp, TAtomdata
   use xcfunctionals, only : xcFunctional
@@ -133,7 +134,7 @@ subroutine readInput(inp, fname)
       call nextline_(fp, iLine, line)
       read(line, *, iostat=iErr) inp%omega
       if (inp%omega < 1.0e-08_dp) then
-        write(*,'(a)') 'Chosen omega too small!'
+        write(stdOut,'(a)') 'Chosen omega too small!'
         stop
       end if
       call checkerror_(fname, line, iLine, iErr)
@@ -144,7 +145,7 @@ subroutine readInput(inp, fname)
       call nextline_(fp, iLine, line)
       read(line, *, iostat=iErr) inp%omega, inp%camAlpha, inp%camBeta
       if (inp%omega < 1.0e-08_dp) then
-        write(*,'(a)') 'Chosen omega too small!'
+        write(stdOut,'(a)') 'Chosen omega too small!'
         stop
       end if
       call checkerror_(fname, line, iLine, iErr)
@@ -257,10 +258,10 @@ subroutine readatom_(fname, fp, iLine, potcomps, tDensitySuperpos, tReadRadDeriv
       ! (positive where abs(r * R(r)) has its maximum)
       imax = maxloc(abs(data(:, 1) * data(:, 2)), dim=1)
       if (data(imax, 2) < 0.0_dp) then
-        write(*, "(A,F5.2,A)") "Wave function negative at the maximum of radial probability&
+        write(stdOut, "(A,F5.2,A)") "Wave function negative at the maximum of radial probability&
             & (r =", data(imax, 1), " Bohr)"
-        write(*, "(A)") "Please change the sign of the wave function (and of its derivatives)!"
-        write(*, "(A,A,A)") "File: '", trim(buffer), "'"
+        write(stdOut, "(A)") "Please change the sign of the wave function (and of its derivatives)!"
+        write(stdOut, "(A,A,A)") "File: '", trim(buffer), "'"
         stop
       end if
     end do
@@ -307,7 +308,7 @@ subroutine readatom_(fname, fp, iLine, potcomps, tDensitySuperpos, tReadRadDeriv
       call TGridorb2_init(atom%ddrho, data(:, 1), data(:, 4))
     else
       if (trim(line) /= "noread") then
-        write(*, "(A,I0,A)") "Line ", iLine, " ignored since density is not needed."
+        write(stdOut, "(A,I0,A)") "Line ", iLine, " ignored since density is not needed."
       end if
     end if
 
@@ -410,7 +411,7 @@ subroutine checkangmoms_(angmoms)
     integer, intent(in) :: angmoms(:)
 
     if (maxval(angmoms) > 4) then
-      write(*,*) "Only angular momentum up to 'f' is allowed."
+      write(stdOut,*) "Only angular momentum up to 'f' is allowed."
       stop
     end if
 
@@ -454,10 +455,10 @@ subroutine error_(txt, fname, line, iLine)
     !> index of erroneous line
     integer, intent(in) :: iLine
 
-    write(*, "(A,A)") "!!! Parsing error: ", txt
-    write(*, "(2X,A,A)") "File: ", trim(fname)
-    write(*, "(2X,A,I0)") "Line number: ", iLine
-    write(*, "(2X,A,A,A)") "Line: '", trim(line), "'"
+    write(stdOut, "(A,A)") "!!! Parsing error: ", txt
+    write(stdOut, "(2X,A,A)") "File: ", trim(fname)
+    write(stdOut, "(2X,A,I0)") "Line number: ", iLine
+    write(stdOut, "(2X,A,A,A)") "Line: '", trim(line), "'"
 
     stop
 
diff --git a/sktwocnt/prog/main.f90 b/sktwocnt/prog/main.F90
similarity index 53%
rename from sktwocnt/prog/main.f90
rename to sktwocnt/prog/main.F90
index 182c423d..50acef8e 100644
--- a/sktwocnt/prog/main.f90
+++ b/sktwocnt/prog/main.F90
@@ -1,7 +1,11 @@
+#:include 'common.fypp'
+
 !> Program to calculate two-center integrals of Slater-Koster tables.
 program main
 
   use common_accuracy, only : dp
+  use common_environment, only : TEnvironment, TEnvironment_init
+  use common_globalenv, only : initGlobalEnv, destructGlobalEnv, stdOut
   use input, only : readInput
   use twocnt, only : TTwocntInp, TIntegMap, get_twocenter_integrals
   use output, only : write_sktables
@@ -18,14 +22,26 @@ program main
   !> resulting Hamiltonian and overlap matrices
   real(dp), allocatable :: skham(:,:), skover(:,:)
 
+  type(TEnvironment) :: env
+
+  call initGlobalEnv()
+  call TEnvironment_init(env)
+#:if WITH_MPI
+  call env%initMpi(1)
+#:endif
   call parse_command_arguments()
 
   call readInput(inp, "sktwocnt.in")
-  write(*, "(A)") "Input done."
+  write(stdOut, "(A)") "Reading input done."
+
+  call get_twocenter_integrals(env, inp, imap, skham, skover)
+  write(stdOut, "(A)") "Two-center integration done."
 
-  call get_twocenter_integrals(inp, imap, skham, skover)
-  write(*, "(A)") "Twocnt done."
+  if (env%tGlobalLead) then
+    call write_sktables(skham, skover)
+  end if
 
-  call write_sktables(skham, skover)
+  call env%destruct()
+  call destructGlobalEnv()
 
 end program main
diff --git a/sktwocnt/prog/output.f90 b/sktwocnt/prog/output.f90
index 43d941e8..aa5a58e6 100644
--- a/sktwocnt/prog/output.f90
+++ b/sktwocnt/prog/output.f90
@@ -2,6 +2,7 @@
 module output
 
   use common_accuracy, only : dp
+  use common_globalenv, only : stdOut
 
   implicit none
   private
@@ -17,8 +18,19 @@ subroutine write_sktables(skham, skover)
     !> Hamiltonian and overlap matrix
     real(dp), intent(in) :: skham(:,:), skover(:,:)
 
-    call write_sktable_("at1-at2.ham.dat", skham)
-    call write_sktable_("at1-at2.over.dat", skover)
+    if (size(skham, dim=2) > 0) then
+      call write_sktable_("at1-at2.ham.dat", skham)
+      write(stdOut, "(A)") "SK-table (Hamiltonian) written."
+    else
+      write(stdOut, "(A)") "Nothing to write (Hamiltonian)."
+    end if
+
+    if (size(skover, dim=2) > 0) then
+      call write_sktable_("at1-at2.over.dat", skover)
+      write(stdOut, "(A)") "SK-table (overlap) written."
+    else
+      write(stdOut, "(A)") "Nothing to write (overlap)."
+    end if
 
   end subroutine write_sktables
 
diff --git a/test/prog/sktable/CMakeLists.txt b/test/prog/sktable/CMakeLists.txt
index 936d4a15..03880d6d 100644
--- a/test/prog/sktable/CMakeLists.txt
+++ b/test/prog/sktable/CMakeLists.txt
@@ -15,7 +15,7 @@ set(fypp_flags ${FYPP_CONFIG_FLAGS})
 list(APPEND fypp_flags -I${projectdir}/common/include -DRELEASE="'${releasename}'")
 
 execute_process(
-  COMMAND ${FYPP} ${fypp_flags}
+  COMMAND ${FYPP} ${fypp_flags} -DMPI_PROCS=${TEST_MPI_PROCS}
   INPUT_FILE ${builddir}/_sktable_tests.fypp
   OUTPUT_FILE ${builddir}/_sktable_tests)
 
@@ -31,5 +31,5 @@ foreach(test IN LISTS tests)
   add_test(
     NAME sktable_${test}
     COMMAND ${PYTHON_INTERPRETER} ${srcdir}/bin/testwithworkdir ${test} ${builddir}
-    -r ${srcdir})
+    -r ${srcdir} -m ${TEST_RUNNER})
 endforeach()
diff --git a/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/_C-C.skf b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/_C-C.skf
new file mode 100644
index 00000000..2bee28f4
--- /dev/null
+++ b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/_C-C.skf
@@ -0,0 +1,42 @@
+0.500000 19
+   0.000000000000E+00  -1.991451862433E-01  -5.008031450092E-01  -4.388315590227E-02   0.000000000000E+00   3.643020862183E-01   3.643020862183E-01   0.000000000000E+00   2.000000000000E+00   2.000000000000E+00
+   1.201000000000E+01 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
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+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   3.219086673683E-04  -1.955462093865E-05   0.000000000000E+00   1.800903426339E-04  -8.155727862988E-05   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -1.974277096770E-04   1.209670522897E-05   0.000000000000E+00  -1.342770484994E-04   2.744297023381E-05
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   1.228469937433E-04  -6.266286348893E-06   0.000000000000E+00   6.767859252726E-05  -1.453381467879E-05   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -1.009520160444E-04   3.006612318733E-06   0.000000000000E+00  -5.703809671614E-05  -2.777821745454E-05
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   4.909066157092E-05  -1.475531792103E-06   0.000000000000E+00   2.236043875471E-05   1.199590708793E-05   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -5.297820724564E-05  -1.320577661839E-06   0.000000000000E+00  -9.753202995221E-06  -5.221413384600E-05
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   2.047400797332E-05   3.252581690915E-07   0.000000000000E+00   1.745201506921E-06   2.062966143228E-05   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -2.154277831327E-05  -3.164061077605E-06   0.000000000000E+00   1.955180355808E-05  -5.571035481656E-05
+
+
+Spline
+12 0.0553585
+112.9353346817185 2.801373701455403 -0.1119994835253462
+0.035 0.0375    0.204206 -35.71077211012958 2016.504000000031 24177.93762071238
+0.0375 0.04    0.12791 -25.17491577974109 2197.838532155373 -120889.6881035729
+0.04 0.0425    0.07682029999999999 -16.45240477090621 1291.165871378576 -57585.58520643491
+0.0425 0.045    0.0428593 -11.07630513663398 859.2739823303137 16659.22892930921
+0.045 0.04533    0.0207993 -6.467574682557872 984.2181993001326 -2167173.572075024
+0.04533 0.045334    0.0186943 -6.526006277016704 -1161.283637054166 353213222.4907721
+0.045334 0.046259    0.0186682 -6.518342311433599 3077.275032831984 -1324559.571220061
+0.046259 0.047184    0.0142234 -4.225362350069925 -598.3777773036936 561811.1110751317
+0.047184 0.0493131    0.0102476 -3.890262342340788 960.6480559297889 -100763.5210502349
+0.0493131 0.0503195    0.00534702 -1.169934109375229 317.0412179256228 -143026.9144497911
+0.0503195 0.0513259    0.00434492 -0.9663840979460291 -114.7856421811885 10348.58893883691
+0.0513259 0.0553585    0.00326664 -1.165980214261954 -83.5411824570522 -5782.515169399558 27636944.82683195 -3877959552.095367
+
+This SPLINE is just a DUMMY-SPLINE!!!!!!!!!!!!!!!
+
diff --git a/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/config b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/config
new file mode 100644
index 00000000..3aab270d
--- /dev/null
+++ b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/config
@@ -0,0 +1 @@
+C C
diff --git a/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/skdef.hsd b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/skdef.hsd
new file mode 100644
index 00000000..6ced8eab
--- /dev/null
+++ b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-conv/skdef.hsd
@@ -0,0 +1,72 @@
+SkdefVersion = 1
+
+Globals {
+  Superposition = density
+  XCFunctional = LDA {}
+}
+
+AtomParameters {
+
+  C {
+    AtomConfig {
+      AtomicNumber = 6
+      Mass = 12.01
+      Occupations {
+	1S = 1.0 1.0
+	2S = 1.0 1.0
+	2P = 2.0 0.0
+      }
+      ValenceShells = 2s 2p
+      Relativistics = None
+    }
+    DftbAtom {
+      ShellResolved = No
+      DensityCompression = PowerCompression { Power = 2; Radius = 7.0 }
+      WaveCompressions = SingleAtomCompressions {
+	S = PowerCompression { Power = 2; Radius = 2.7 }
+	P = PowerCompression { Power = 2; Radius = 2.7 }
+      }
+    }
+  }
+
+}
+
+
+OnecenterParameters {
+
+  $StandardDeltaFilling {
+    DeltaFilling = 0.01
+  }
+
+  C {
+    $StandardDeltaFilling
+    Calculator = SlaterAtom {
+      Exponents {
+	S = 0.5 1.14 2.62 6.0
+	P = 0.5 1.14 2.62 6.0
+      }
+      MaxPowers {
+	S = 3
+	P = 3
+      }
+    }
+  }
+
+}
+
+TwoCenterParameters {
+
+  $EqGrid = EquidistantGrid {
+      GridStart = 8.0
+      GridSeparation = 0.5
+      Tolerance = 5e-5
+      MaxDistance = 12.0
+  }
+
+  $SkTwocnt_300_150 = Sktwocnt {
+    IntegrationPoints = 300 150
+  }
+
+  C-C { Grid = $EqGrid; Calculator = $SkTwocnt_300_150 }
+
+}
diff --git a/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/_C-C.skf b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/_C-C.skf
new file mode 100644
index 00000000..7c6e45ff
--- /dev/null
+++ b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/_C-C.skf
@@ -0,0 +1,48 @@
+0.500000 25
+   0.000000000000E+00  -1.991451862433E-01  -5.008031450092E-01  -4.388315590227E-02   0.000000000000E+00   3.643020862183E-01   3.643020862183E-01   0.000000000000E+00   2.000000000000E+00   2.000000000000E+00
+   1.201000000000E+01 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   3.219086673683E-04  -1.955462093865E-05   0.000000000000E+00   1.800903426339E-04  -8.155727862988E-05   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -1.974277096770E-04   1.209670522897E-05   0.000000000000E+00  -1.342770484994E-04   2.744297023381E-05
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   1.228469937433E-04  -6.266286348893E-06   0.000000000000E+00   6.767859252726E-05  -1.453381467879E-05   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -1.009520160444E-04   3.006612318733E-06   0.000000000000E+00  -5.703809671614E-05  -2.777821745454E-05
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   4.909066157092E-05  -1.475531792103E-06   0.000000000000E+00   2.236043875471E-05   1.199590708793E-05   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -5.297820724564E-05  -1.320577661839E-06   0.000000000000E+00  -9.753202995221E-06  -5.221413384600E-05
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   2.047400797332E-05   3.252581690915E-07   0.000000000000E+00   1.745201506921E-06   2.062966143228E-05   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -2.154277831327E-05  -3.164061077605E-06   0.000000000000E+00   1.955180355808E-05  -5.571035481656E-05
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   7.063622131663E-06   9.625515572233E-07   0.000000000000E+00  -8.526308665088E-06   1.996835788813E-05   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   3.430861462875E-07  -3.499518052138E-06   0.000000000000E+00   3.427845533508E-05  -4.541637226559E-05
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -6.486186365540E-07   1.054240409289E-06   0.000000000000E+00  -1.296048334703E-05   1.418623554365E-05   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   1.383793345544E-05  -2.963448902885E-06   0.000000000000E+00   3.737537198328E-05  -2.791987934497E-05
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -5.183000983418E-06   8.635250595737E-07   0.000000000000E+00  -1.336257931418E-05   6.113292508301E-06   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   1.999995439150E-05  -2.034913172819E-06   0.000000000000E+00   3.251616618959E-05  -8.763086604784E-06
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -7.274730120167E-06   5.472458444468E-07   0.000000000000E+00  -1.106775078140E-05  -2.103818266608E-06   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   2.061203707744E-05  -1.047185407574E-06   0.000000000000E+00   2.341202817384E-05   8.155530513834E-06
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -7.468690382990E-06   2.117453765767E-07   0.000000000000E+00  -7.331090226859E-06  -8.988969613913E-06   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   1.771796717585E-05  -1.962395798075E-07   0.000000000000E+00   1.310077315003E-05   2.069459751665E-05
+   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00  -6.386677784830E-06  -7.702235117823E-08   0.000000000000E+00  -3.222548200783E-06  -1.374764544683E-05   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   0.000000000000E+00   1.312792135917E-05   4.316364845240E-07   0.000000000000E+00   3.641528826244E-06   2.818443964454E-05
+
+
+Spline
+12 0.0553585
+112.9353346817185 2.801373701455403 -0.1119994835253462
+0.035 0.0375    0.204206 -35.71077211012958 2016.504000000031 24177.93762071238
+0.0375 0.04    0.12791 -25.17491577974109 2197.838532155373 -120889.6881035729
+0.04 0.0425    0.07682029999999999 -16.45240477090621 1291.165871378576 -57585.58520643491
+0.0425 0.045    0.0428593 -11.07630513663398 859.2739823303137 16659.22892930921
+0.045 0.04533    0.0207993 -6.467574682557872 984.2181993001326 -2167173.572075024
+0.04533 0.045334    0.0186943 -6.526006277016704 -1161.283637054166 353213222.4907721
+0.045334 0.046259    0.0186682 -6.518342311433599 3077.275032831984 -1324559.571220061
+0.046259 0.047184    0.0142234 -4.225362350069925 -598.3777773036936 561811.1110751317
+0.047184 0.0493131    0.0102476 -3.890262342340788 960.6480559297889 -100763.5210502349
+0.0493131 0.0503195    0.00534702 -1.169934109375229 317.0412179256228 -143026.9144497911
+0.0503195 0.0513259    0.00434492 -0.9663840979460291 -114.7856421811885 10348.58893883691
+0.0513259 0.0553585    0.00326664 -1.165980214261954 -83.5411824570522 -5782.515169399558 27636944.82683195 -3877959552.095367
+
+This SPLINE is just a DUMMY-SPLINE!!!!!!!!!!!!!!!
+
diff --git a/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/config b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/config
new file mode 100644
index 00000000..3aab270d
--- /dev/null
+++ b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/config
@@ -0,0 +1 @@
+C C
diff --git a/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/skdef.hsd b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/skdef.hsd
new file mode 100644
index 00000000..901a17cd
--- /dev/null
+++ b/test/prog/sktable/LDA-PW91/Non-Relativistic/Dynamic-noconv/skdef.hsd
@@ -0,0 +1,72 @@
+SkdefVersion = 1
+
+Globals {
+  Superposition = density
+  XCFunctional = LDA {}
+}
+
+AtomParameters {
+
+  C {
+    AtomConfig {
+      AtomicNumber = 6
+      Mass = 12.01
+      Occupations {
+	1S = 1.0 1.0
+	2S = 1.0 1.0
+	2P = 2.0 0.0
+      }
+      ValenceShells = 2s 2p
+      Relativistics = None
+    }
+    DftbAtom {
+      ShellResolved = No
+      DensityCompression = PowerCompression { Power = 2; Radius = 7.0 }
+      WaveCompressions = SingleAtomCompressions {
+	S = PowerCompression { Power = 2; Radius = 2.7 }
+	P = PowerCompression { Power = 2; Radius = 2.7 }
+      }
+    }
+  }
+
+}
+
+
+OnecenterParameters {
+
+  $StandardDeltaFilling {
+    DeltaFilling = 0.01
+  }
+
+  C {
+    $StandardDeltaFilling
+    Calculator = SlaterAtom {
+      Exponents {
+	S = 0.5 1.14 2.62 6.0
+	P = 0.5 1.14 2.62 6.0
+      }
+      MaxPowers {
+	S = 3
+	P = 3
+      }
+    }
+  }
+
+}
+
+TwoCenterParameters {
+
+  $EqGrid = EquidistantGrid {
+      GridStart = 8.0
+      GridSeparation = 0.5
+      Tolerance = 5e-6
+      MaxDistance = 12.0
+  }
+
+  $SkTwocnt_300_150 = Sktwocnt {
+    IntegrationPoints = 300 150
+  }
+
+  C-C { Grid = $EqGrid; Calculator = $SkTwocnt_300_150 }
+
+}
diff --git a/test/prog/sktable/bin/testwithworkdir b/test/prog/sktable/bin/testwithworkdir
index e0f669d5..fbd034dd 100644
--- a/test/prog/sktable/bin/testwithworkdir
+++ b/test/prog/sktable/bin/testwithworkdir
@@ -51,15 +51,16 @@ def main(cmdlineargs=None):
     with open(os.path.join(cwd, 'config'), 'r') as fd:
         config = fd.readline()
 
+    slateratom_bin = os.path.abspath('../../../slateratom/prog/slateratom')
+    sktwocnt_bin = ' '.join(
+        [args.mpi_prefix, os.path.abspath('../../../sktwocnt/prog/sktwocnt')])
+
     cmd = 'python3 ' \
         + os.path.abspath('../../../../sktools/src/sktools/scripts/skgen.py') \
         + ' ' + '-c {} '.format(
             os.path.join(cwd, 'skdef.hsd')) \
-        + '-o {} '.format(os.path.abspath(
-            '../../../slateratom/prog/slateratom')) \
-        + '-t {} '.format(
-            os.path.abspath('../../../sktwocnt/prog/sktwocnt')) \
-        + 'sktable ' + config
+        + '-o "{}" '.format(slateratom_bin) \
+        + '-t "{}" '.format(sktwocnt_bin) + 'sktable ' + config
 
     # remove _build folder and old files if present
     shutil.rmtree(os.path.join(cwd, '_build'), ignore_errors=True)
@@ -110,6 +111,10 @@ def parse_cmdline_args(cmdlineargs=None):
                         dest='templateroot', default=os.getcwd(), type=str,
                         help=msg)
 
+    msg = 'prefix for calling MPI-enabled binaries'
+    parser.add_argument('-m', '--mpi-prefix', action='store', dest='mpi_prefix',
+                        default='', type=str, help=msg)
+
     args = parser.parse_args(cmdlineargs)
 
     return args
diff --git a/test/prog/sktable/tests b/test/prog/sktable/tests
index af0e0790..69c729ce 100644
--- a/test/prog/sktable/tests
+++ b/test/prog/sktable/tests
@@ -3,6 +3,8 @@
 
 #:include 'common.fypp'
 
+LDA-PW91/Non-Relativistic/Dynamic-conv
+LDA-PW91/Non-Relativistic/Dynamic-noconv
 LDA-PW91/Non-Relativistic/Power
 LDA-PW91/Non-Relativistic/WS
 GGA-PBE96/Non-Relativistic
diff --git a/utils/export/skprogs-config.cmake.in b/utils/export/skprogs-config.cmake.in
index 156bfc57..e53ab017 100644
--- a/utils/export/skprogs-config.cmake.in
+++ b/utils/export/skprogs-config.cmake.in
@@ -1,10 +1,21 @@
 @PACKAGE_INIT@
 
+# Global DFTB+ config options
+set(SkProgs_WITH_MPI @WITH_MPI@)
+
 include(CMakeFindDependencyMacro)
 
 if(NOT TARGET SkProgs::sktwocnt)
+
+  if(SkProgs_WITH_MPI)
+    if(NOT TARGET MpiFx::MpiFx)
+      find_dependency(MpiFx)
+    endif()
+  endif()
+
   if (NOT TARGET Libxc::xc)
     find_dependency(Libxc)
   endif()
   include(${CMAKE_CURRENT_LIST_DIR}/skprogs-targets.cmake)
+
 endif()
diff --git a/utils/test/check_submodule_commits b/utils/test/check_submodule_commits
new file mode 100755
index 00000000..d305dc4a
--- /dev/null
+++ b/utils/test/check_submodule_commits
@@ -0,0 +1,112 @@
+#!/usr/bin/env python3
+
+"""Checks the submodule commit IDs in integration CMake files."""
+
+import argparse
+import configparser
+import re
+import subprocess
+import sys
+
+_DESCRIPTION = """
+Checks (and optionally updates) the submodule commit IDs in the integration
+CMake files. It loops over all git submodules, reads their commit hashes and
+checks, whether it matches the commit ID in the CMakeLists.txt in the parent
+folder. The script must be run from the projects root folder and the git command
+should work.
+"""
+
+_PAT_SUBMOD_COMMIT = re.compile(
+    r"""^[-+ ]*(?P<commit>[0-9a-f]+)
+    \s+
+    external/(?P<submodule>[0-9a-zA-Z_-]+)/origin
+    \s+.*$""",
+    re.MULTILINE | re.VERBOSE)
+
+_PAT_SPECIAL_CHAR = re.compile(r"[-_]")
+
+_SPECIAL_CHAR_REPLACEMENT = "_"
+
+def main():
+    """Main script"""
+    args = _parse_arguments()
+    result = subprocess.run(["git", "submodule", "status"],
+                            stdout=subprocess.PIPE, check=True)
+    output = result.stdout.decode('ascii')
+    if args.check:
+        gitconfig = configparser.ConfigParser()
+        gitconfig.read('.git/config')
+    allsync = True
+    with open("CMakeLists.txt", "r") as fp:
+        origcontent = fp.read()
+    content = origcontent
+    for match in _PAT_SUBMOD_COMMIT.finditer(output):
+        commit, submodule = match.groups()
+        if args.check:
+            locale = ('submodule "external/%s/origin"' % submodule)
+            active = gitconfig.get(locale, 'active')
+            if active == 'true':
+                url = gitconfig.get(locale, 'url')
+                _check_submodule_url(content, submodule, url)
+        newcontent, nn = _replace_submodule_commit(content, submodule, commit)
+        if nn < 1:
+            print("! Commit for submodule {} was NOT FOUND".format(submodule))
+            allsync = False
+            continue
+        sync = (newcontent == content)
+        if sync:
+            print("+ Commit ID for submodule {} matches.".format(submodule))
+        elif args.update:
+            content = newcontent
+            print("* Commit for submodule {} has been updated."\
+                  .format(submodule))
+        else:
+            print("! Commit for submodule {} DOES NOT MATCH!".format(submodule))
+            allsync = False
+    if content != origcontent:
+        with open("CMakeLists.txt", "w") as fp:
+            fp.write(content)
+    if not allsync:
+        sys.exit(1)
+
+
+def _parse_arguments():
+    """Returns command line arguments"""
+    parser = argparse.ArgumentParser(description=_DESCRIPTION)
+    msg = "Whether the commits should be updated in the CMakeLists.txt files"
+    parser.add_argument("-u", "--update", action='store_true', help=msg)
+    msg = "Check consistency between CMakeLists.txt and submodules"
+    parser.add_argument("-c", "--check", action='store_true', help=msg)
+    return parser.parse_args()
+
+
+def _replace_submodule_commit(content, submodule, commit):
+    """Replaces the commit id in the CMakeLists.txt file content"""
+    submodule_normed = submodule.upper()
+    submodule_normed = re.sub(
+        _PAT_SPECIAL_CHAR, _SPECIAL_CHAR_REPLACEMENT, submodule_normed)
+
+    newcontent, nsubs = re.subn(
+        r"set\({}_GIT_TAG (['\"]).+\1\)".format(submodule_normed),
+        'set({}_GIT_TAG "{}")'.format(submodule_normed, commit),
+        content)
+    return newcontent, nsubs
+
+
+def _check_submodule_url(content, submodule, url):
+    """Checks consistency of the submodule url in the CMakeLists.txt file"""
+    submodule_normed = submodule.upper()
+    submodule_normed = re.sub(
+        _PAT_SPECIAL_CHAR, _SPECIAL_CHAR_REPLACEMENT, submodule_normed)
+    match = re.findall(
+        r"set\({}_GIT_REPOSITORY \"({})(\.git)?\"\)".format(submodule_normed, url),
+        content)
+    if (len(match) == 0):
+        print('** {} : mismatch between .git/config and CMakeLists.txt'.format(submodule))
+    else:
+        if (match[0][1] == '.git'):
+            print("* {} : bare vs non-bare repository address in CMakeLists.txt and .git/config".format(submodule))
+
+
+if __name__ == '__main__':
+    main()