Elegant and intuitive data structures for quantum chemistry, featuring seamless Jupyter Notebook visualizations. Also featuring NIST/CODATA2022 core physical constants and a Periodic Table.
Inspired by QCElemental. Built for consistency and rapid development.
qcio
works in harmony with a suite of other quantum chemistry tools for fast, structured, and interoperable quantum chemistry.
- qcio - Elegant and intuitive data structures for quantum chemistry, featuring seamless Jupyter Notebook visualizations. Documentation
- qcparse - A library for efficient parsing of quantum chemistry data into structured
qcio
objects. - qcop - A package for operating quantum chemistry programs using
qcio
standardized data structures. Compatible withTeraChem
,psi4
,QChem
,NWChem
,ORCA
,Molpro
,geomeTRIC
and many more. - BigChem - A distributed application for running quantum chemistry calculations at scale across clusters of computers or the cloud. Bring multi-node scaling to your favorite quantum chemistry program.
ChemCloud
- A web application and associated Python client for exposing a BigChem cluster securely over the internet.
pip install qcio
qcio
is built around a simple mental model: Input
objects are used to define inputs for a quantum chemistry program, and Output
objects are used to capture the outputs from a quantum chemistry program.
All qcio
objects can be serialized and saved to disk by calling .save("filename.json")
and loaded from disk by calling .open("filename.json")
. qcio
supports json
, yaml
, and toml
file formats. Binary data will be automatically base64 encoded and decoded when saving and loading.
from qcio import Structure, ProgramInput
# xyz files or saved Structure objects can be opened from disk
caffeine = Structure.open("caffeine.xyz")
# Define the program input
prog_input = ProgramInput(
structure=caffeine,
calctype="energy",
keywords={"purify": "no", "restricted": False},
model={"method": "hf", "basis": "sto-3g"},
extras={"comment": "This is a comment"}, # Anything extra not in the schema
)
# Binary or other files used as input can be added
prog_input.add_file("wfn.dat")
prog_input.keywords["initial_guess"] = "wfn.dat"
# Save the input to disk in json, yaml, or toml format
prog_input.save("input.json")
# Open the input from disk
prog_input = ProgramInput.open("input.json")
Structure
objects can be opened from and saved as xyz files or saved to disk as .json
, .yaml
, or .toml
formats by changing the extension of the file. For .xyz
files precision can be controlled by passing the precision
argument to the save
method.
caffeine = Structure.open("caffeine.xyz")
caffeine.save("caffeine2.json", precision=6)
caffeine.save("caffeine.toml")
DualProgramInput
objects can be used to power workflows that require multiple QC programs. For example, a geometry optimization workflow might use geomeTRIC
to power the optimization and use terachem
to compute the energies and gradients.
from qcio import Structure, DualProgramInput
# xyz files or saved Structure objects can be opened from disk
caffeine = Structure.open("caffeine.xyz")
# Define the program input
prog_input = DualProgramInput(
structure=caffeine,
calctype="optimization",
keywords={"maxiter": 250},
subprogram="terachem",
subprogram_args = {
"model": {"method": "hf", "basis": "sto-3g"},
"keywords": {"purify": "no", "restricted": False},
},
extras={"comment": "This is a comment"}, # Anything extra not in the schema
)
qcio
also supports the native file formats of each QC program with a FileInput
object. Assume you have a directory like this with your input files for psi4
:
psi4/
input.dat
geometry.xyz
wfn.dat
You can collect these native files and any associated command line arguments needed to specify a calculation into a FileInput
object like this:
from qcio import FileInput
psi4_input = FileInput.from_directory("psi4")
# All input files will be loaded into the `files` attribute
psi4_input.files
# {'input.dat': '...', 'geometry.xyz': '...', 'wfn.dat': '...'}
# Add psi4 command line args to the input
psi4_input.cmdline_args.extend(["-n", "4"])
# Files can be dumped to a directory for a calculation
psi4_input.save_files("psi4")
Objects are immutable by default so if you want to modify an object cast it to a dictionary, make the desired modification, and then instantiate a new object. This prevents accidentally modifying objects that may already be referenced in other calculations--perhaps as .input_data
on an Output
object.
# Cast to a dictionary and modify
new_input_dict = prog_input.model_dumps()
new_input_dict["model"]["method"] = "b3lyp"
# Instantiate a new object
new_prog_input = ProgramInput(**new_input_dict)
All computations result in a ProgramOutput
object that encapsulates the core results, files, stdout, and additional details of the calculation. A ProgramOutput
object has the following attributes:
output.input_data # Input data used by the QC program
output.success # Whether the calculation succeeded or failed
output.results # All structured results from the calculation
output.results.files # Any files returned by the calculation
output.stdout # Stdout log from the calculation
output.pstdout # Shortcut to print out the stdout in human readable format
output.provenance # Provenance information about the calculation
output.extras # Any extra information not in the schema
The .results
attribute on a ProgramOutput
is polymorphic and may be either Files
, SinglePointResults
or OptimizationResults
depending on the type of calculation requested. Available attributes for each result type can be found by calling dir()
on the object.
dir(output.results)
Results can be saved to disk in json, yaml, or toml format by calling .save("filename.{json/yaml/toml}")
and loaded from disk by calling .open("filename.{json/yaml/toml}")
.
Visualize all your results with a single line of code!
First install the visualization module:
pip install qcio[view]
or if your shell requires ''
around arguments with brackets:
pip install 'qcio[view]'
Then in a Jupyter notebook import the qcio
view module and call view.view(...)
passing it one or any number of qcio
objects you want to visualizing including Structure
objects or any ProgramOutput
object. You may also pass an array of titles
and/or subtitles
to add additional information to the molecular structure display. If no titles are passed qcio
with look for Structure
identifiers such as a name or SMILES to label the Structure
.
Seamless visualizations for ProgramOutput
objects make results analysis easy!
Single point calculations display their results in a table.
If you want to use the HTML generated by the viewer to build your own dashboards use the functions inside of qcio.view.py
that begin with the word generate_
to create HTML you can insert into any dashboard.
Core physical constants are available in the constants
module. The source of all values is documented and kept up-to-date with the latest NIST/CODATA2022 values.
from qcio import constants
constants.BOHR_TO_ANGSTROM
Periodic Table is also available from the constants
module.
from qcio.constants import periodic_table as pt
pt.He.symbol
pt.He.number
pt.He.name
pt.Ht.mass
pt.He.group
pt.He.period
pt.He.block
pt.He.electron_confg
group_6 = pt.group(6)
period_3 = pt.period(3)
# Check Data Source
pt.data_source
pt.data_url
If you have any issues with qcio
or would like to request a feature, please open an issue.