Feature: EXX PW supports a ecut different from ecutrho

source/source_io/module_parameter/input_parameter.h

@@ -656,6 +656,7 @@ struct Input_para
     bool exx_gamma_extrapolation = true; // gamma point extrapolation for exx, https://doi.org/10.1103/PhysRevB.79.205114
     std::string exx_thr_type = "density"; // threshold type for exx outer loop, energy or density
     double exx_ene_thr = 1e-5; // threshold for exx outer loop when exx_thr_type = energy
+    double ecutexx = 0.0; // energy cutoff for exx calculation, Ry
 
     // ====   #Parameters (23.XC external parameterization) ========
     /*

source/source_io/read_input_item_other.cpp

@@ -571,6 +571,18 @@ void ReadInput::item_others()
         };
         this->add_item(item);
     }
+    {
+        Input_Item item("ecutexx");
+        item.annotation = "energy cutoff for exx calculation, Ry";
+        read_sync_double(input.ecutexx);
+        item.check_value = [](const Input_Item& item, const Parameter& para) {
+            if (para.input.ecutexx < 0)
+            {
+                ModuleBase::WARNING_QUIT("ReadInput", "ecutexx must >= 0");
+            }
+        };
+        this->add_item(item);
+    }
 
 }
 } // namespace ModuleIO

source/source_pw/module_pwdft/operator_pw/op_exx_pw.cpp

@@ -76,15 +76,22 @@ OperatorEXXPW<T, Device>::OperatorEXXPW(const int* isk_in,
     tpiba = ucell->tpiba;
     Real tpiba2 = tpiba * tpiba;
 
+    // initialize rhopw_dev
+    double ecut_exx = PARAM.inp.ecutexx;
+    if (ecut_exx == 0.0)
+    {
+        ecut_exx = PARAM.inp.ecutrho;
+    }
+
     rhopw_dev = new ModulePW::PW_Basis(wfcpw->get_device(), rhopw->get_precision());
     rhopw_dev->fft_bundle.setfft(wfcpw->get_device(), rhopw->get_precision());
 #ifdef __MPI
     rhopw_dev->initmpi(rhopw->poolnproc, rhopw->poolrank, rhopw->pool_world);
 #endif
     // here we can actually use different ecut to init the grids
-    rhopw_dev->initgrids(rhopw->lat0, rhopw->latvec, rhopw->gridecut_lat * rhopw->tpiba2);
+    rhopw_dev->initgrids(rhopw->lat0, rhopw->latvec, ecut_exx);
     rhopw_dev->initgrids(rhopw->lat0, rhopw->latvec, rhopw->nx, rhopw->ny, rhopw->nz);
-    rhopw_dev->initparameters(rhopw->gamma_only, rhopw->ggecut * rhopw->tpiba2, rhopw->distribution_type, rhopw->xprime);
+    rhopw_dev->initparameters(rhopw->gamma_only, ecut_exx, rhopw->distribution_type, rhopw->xprime);
     rhopw_dev->setuptransform();
     rhopw_dev->collect_local_pw();