From 714478e868a36444df368355b19c07c011c6758f Mon Sep 17 00:00:00 2001
From: hongriTianqi <z.hao.1@163.com>
Date: Wed, 28 Aug 2024 17:24:59 +0800
Subject: [PATCH] add energy_stable count to energy threshold

---
 source/module_esolver/esolver_fp.h        |  2 ++
 source/module_esolver/esolver_ks.cpp      | 15 +++++++++++++--
 source/module_esolver/esolver_ks_lcao.cpp |  4 ++--
 source/module_ri/Exx_LRI_interface.h      |  2 +-
 source/module_ri/Exx_LRI_interface.hpp    |  4 ++--
 5 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/source/module_esolver/esolver_fp.h b/source/module_esolver/esolver_fp.h
index 4d5fcf5c41..a90f63a170 100644
--- a/source/module_esolver/esolver_fp.h
+++ b/source/module_esolver/esolver_fp.h
@@ -63,6 +63,8 @@ namespace ModuleESolver
 
         bool conv_elec; // If electron density is converged in scf.
 
+        int energy_stable_count = 0; // Counter for stable energy convergence.
+
       protected:
         //! Something to do after SCF iterations when SCF is converged or comes to the max iter step.
         virtual void after_scf(const int istep);
diff --git a/source/module_esolver/esolver_ks.cpp b/source/module_esolver/esolver_ks.cpp
index 8226184e39..c8ca1bb4e9 100644
--- a/source/module_esolver/esolver_ks.cpp
+++ b/source/module_esolver/esolver_ks.cpp
@@ -425,6 +425,7 @@ void ESolver_KS<T, Device>::runner(const int istep, UnitCell& ucell)
     bool firstscf = true;
     this->conv_elec = false;
     this->niter = this->maxniter;
+    this->energy_stable_count = 0;
 
     // 4) SCF iterations
     double diag_ethr = GlobalV::PW_DIAG_THR;
@@ -644,8 +645,18 @@ void ESolver_KS<T, Device>::iter_finish(int& iter)
     // add a energy threshold for SCF convergence
     if (this->conv_elec == 0) // only check when density is not converged
     {
-        this->conv_elec
-            = (iter != 1 && std::abs(this->pelec->f_en.etot_delta * ModuleBase::Ry_to_eV) < this->scf_ene_thr);
+        if (iter != 1 && std::abs(this->pelec->f_en.etot_delta * ModuleBase::Ry_to_eV) < this->scf_ene_thr)
+        {
+            this->energy_stable_count++;
+        }
+        else
+        {
+            this->energy_stable_count = 0;
+        }
+        if (this->energy_stable_count >= 2) // energy stable for 2 steps
+        {
+            this->conv_elec = true;
+        }
     }
 }
 
diff --git a/source/module_esolver/esolver_ks_lcao.cpp b/source/module_esolver/esolver_ks_lcao.cpp
index 177b791b98..39062d69ba 100644
--- a/source/module_esolver/esolver_ks_lcao.cpp
+++ b/source/module_esolver/esolver_ks_lcao.cpp
@@ -998,7 +998,7 @@ void ESolver_KS_LCAO<TK, TR>::iter_finish(int& iter)
                 PARAM.inp.nspin,
                 iter,
                 this->pelec->f_en.etot,
-                this->scf_ene_thr);
+                this->energy_stable_count);
         }
         else
         {
@@ -1009,7 +1009,7 @@ void ESolver_KS_LCAO<TK, TR>::iter_finish(int& iter)
                 PARAM.inp.nspin,
                 iter,
                 this->pelec->f_en.etot,
-                this->scf_ene_thr);
+                this->energy_stable_count);
         }
     }
 #endif
diff --git a/source/module_ri/Exx_LRI_interface.h b/source/module_ri/Exx_LRI_interface.h
index 9f16e95acc..2377857470 100644
--- a/source/module_ri/Exx_LRI_interface.h
+++ b/source/module_ri/Exx_LRI_interface.h
@@ -53,7 +53,7 @@ class Exx_LRI_Interface
         const int& nspin,
         int& iter,
         const double& etot,
-        const double& scf_ene_thr);
+        const int& energy_stable_count);
     int two_level_step = 0;
     double etot_last_outer_loop = 0.0;
 private:
diff --git a/source/module_ri/Exx_LRI_interface.hpp b/source/module_ri/Exx_LRI_interface.hpp
index aaa338845d..228256f0ed 100644
--- a/source/module_ri/Exx_LRI_interface.hpp
+++ b/source/module_ri/Exx_LRI_interface.hpp
@@ -130,7 +130,7 @@ bool Exx_LRI_Interface<T, Tdata>::exx_after_converge(
     const int& nspin,
     int& iter,
     const double& etot,
-    const double& scf_ene_thr)
+    const int& energy_stable_count)
 {   // only called if (GlobalC::exx_info.info_global.cal_exx)
     auto restart_reset = [this]()
         { // avoid calling restart related procedure in the subsequent ion steps
@@ -169,7 +169,7 @@ bool Exx_LRI_Interface<T, Tdata>::exx_after_converge(
             // exx converged or get max exx steps
             if (this->two_level_step == GlobalC::exx_info.info_global.hybrid_step
                 || (iter == 1 && this->two_level_step != 0) // density convergence of outer loop
-                || (ediff < scf_ene_thr && this->two_level_step != 0))   //energy convergence of outer loop
+                || (energy_stable_count >= 2 && this->two_level_step != 0))   //energy convergence of outer loop
             {
                 restart_reset();
                 return true;