Feature: add class PotXC_FDM and Pot_Cosikr (#6962)

Co-authored-by: linpz <linpz@mail.ustc.edu.cn>

Author: linpeize

source/source_estate/CMakeLists.txt

@@ -18,6 +18,8 @@ list(APPEND objects
     module_pot/pot_ml_exx.cpp
     module_pot/pot_ml_exx_label.cpp
     module_pot/pot_sep.cpp
+    module_pot/pot_xc_fdm.cpp
+    module_pot/pot_cosikr.cpp
     module_charge/chgmixing.cpp
     module_charge/charge.cpp
     module_charge/charge_init.cpp

source/source_estate/module_pot/pot_cosikr.cpp

@@ -0,0 +1,53 @@
+//=======================
+// AUTHOR : Peize Lin
+// DATE :   2025-10-05
+//=======================
+
+#include "pot_cosikr.h"
+
+#include <cmath>
+
+namespace elecstate
+{
+
+Pot_Cosikr::Pot_Cosikr(
+		const ModulePW::PW_Basis* rho_basis_in,
+		const ModuleBase::Vector3<double> &kvec_d_in,
+		const std::vector<double> &phase_in,
+		const std::vector<double> &amplitude_in)
+	:kvec_d(kvec_d_in),
+	 phase(phase_in),
+	 amplitude(amplitude_in)
+{
+	this->rho_basis_ = rho_basis_in;
+	this->dynamic_mode = true;
+	this->fixed_mode = false;
+}
+
+
+void Pot_Cosikr::cal_v_eff(const Charge*const chg, const UnitCell*const ucell, ModuleBase::matrix &v_eff)
+{
+	ModuleBase::TITLE("Pot_Cosikr", "cal_v_eff");
+	ModuleBase::timer::tick("Pot_Cosikr", "cal_veff");
+	assert(v_eff.nr == this->phase.size());
+	assert(v_eff.nr == this->amplitude.size());
+	int ir = 0;
+	for (int ix = 0; ix < this->rho_basis_->nx; ++ix)
+	{
+		const double phase_x = this->kvec_d.x * ix / this->rho_basis_->nx;
+		for (int iy = 0; iy < this->rho_basis_->ny; ++iy)
+		{
+			const double phase_xy = phase_x + this->kvec_d.y * iy / this->rho_basis_->ny;
+			for (int iz = this->rho_basis_->startz_current; iz < this->rho_basis_->startz_current + this->rho_basis_->nplane; ++iz)
+			{
+				const double phase_xyz = phase_xy + this->kvec_d.z * iz / this->rho_basis_->nz;
+				for(int is=0; is<v_eff.nr; ++is)
+					v_eff(is,ir) += this->amplitude[is] * std::cos((phase_xyz + this->phase[is]) * ModuleBase::TWO_PI);
+				++ir;
+			}
+		}
+	}
+	ModuleBase::timer::tick("Pot_Cosikr", "cal_veff");
+}
+
+}

source/source_estate/module_pot/pot_cosikr.h

@@ -0,0 +1,36 @@
+//=======================
+// AUTHOR : Peize Lin
+// DATE :   2025-10-05
+//=======================
+
+#ifndef POT_COSIKR_H
+#define POT_COSIKR_H
+
+#include "pot_base.h"
+#include "source_base/vector3.h"
+
+
+namespace elecstate
+{
+
+// ampitude * cos( 2pi*( k * r + phase ) )
+class Pot_Cosikr : public PotBase
+{
+  public:
+	Pot_Cosikr(
+		const ModulePW::PW_Basis* rho_basis_in,
+		const ModuleBase::Vector3<double> &kvec_d_in,
+		const std::vector<double> &phase_in,
+		const std::vector<double> &amplitude_in);
+	
+	void cal_v_eff(const Charge*const chg, const UnitCell*const ucell, ModuleBase::matrix &v_eff) override;
+
+  private:
+	const ModuleBase::Vector3<double> kvec_d;
+	const std::vector<double> phase;
+	const std::vector<double> amplitude;
+};
+
+}
+
+#endif

source/source_estate/module_pot/pot_xc.cpp

@@ -1,6 +1,7 @@
 #include "pot_xc.h"
 
 #include "source_base/timer.h"
+#include "source_hamilt/module_xc/xc_functional.h"
 
 #ifdef USE_LIBXC
 #include "source_hamilt/module_xc/xc_functional_libxc.h"

source/source_estate/module_pot/pot_xc_fdm.cpp

@@ -0,0 +1,59 @@
+//=======================
+// AUTHOR : Peize Lin
+// DATE :   2025-10-01
+//=======================
+
+#include "pot_xc_fdm.h"
+#include "source_hamilt/module_xc/xc_functional.h"
+
+namespace elecstate
+{
+
+PotXC_FDM::PotXC_FDM(
+	const ModulePW::PW_Basis* rho_basis_in,
+	const Charge*const chg_0_in,
+	const UnitCell*const ucell)
+	: chg_0(chg_0_in)
+{
+	this->rho_basis_ = rho_basis_in;
+	this->dynamic_mode = true;
+	this->fixed_mode = false;
+
+	const std::tuple<double, double, ModuleBase::matrix> etxc_vtxc_v_0
+		= XC_Functional::v_xc(this->chg_0->nrxx, this->chg_0, ucell);
+	this->v_xc_0 = std::get<2>(etxc_vtxc_v_0);
+}
+
+void PotXC_FDM::cal_v_eff(
+	const Charge*const chg_1,
+	const UnitCell*const ucell,
+	ModuleBase::matrix& v_eff)
+{
+	ModuleBase::TITLE("PotXC_FDM", "cal_veff");
+	ModuleBase::timer::tick("PotXC_FDM", "cal_veff");
+
+	assert(this->chg_0->nrxx == chg_1->nrxx);
+	assert(this->chg_0->nspin == chg_1->nspin);
+
+	Charge chg_01;
+	chg_01.set_rhopw(chg_1->rhopw);
+	chg_01.allocate(chg_1->nspin, chg_01.kin_density());
+
+	for(int ir=0; ir<chg_01.nrxx; ++ir)
+	{
+		for(int is=0; is<chg_01.nspin; ++is)
+			{ chg_01.rho[is][ir] = chg_0->rho[is][ir] + chg_1->rho[is][ir]; }
+		chg_01.rho_core[ir] = chg_0->rho_core[ir] + chg_1->rho_core[ir];
+	}
+
+	const std::tuple<double, double, ModuleBase::matrix> etxc_vtxc_v_01
+		= XC_Functional::v_xc(chg_01.nrxx, &chg_01, ucell);
+	const ModuleBase::matrix &v_xc_01 = std::get<2>(etxc_vtxc_v_01);
+
+	v_eff += v_xc_01 - this->v_xc_0;
+
+	ModuleBase::timer::tick("PotXC_FDM", "cal_veff");
+}
+
+} // namespace elecstate
+

source/source_estate/module_pot/pot_xc_fdm.h

@@ -0,0 +1,34 @@
+//=======================
+// AUTHOR : Peize Lin
+// DATE :   2025-10-01
+//=======================
+
+#ifndef POTXC_FDM_H
+#define POTXC_FDM_H
+
+#include "pot_base.h"
+
+namespace elecstate
+{
+
+class PotXC_FDM : public PotBase
+{
+public:
+
+	PotXC_FDM(
+		const ModulePW::PW_Basis* rho_basis_in,
+		const Charge*const chg_0_in,
+		const UnitCell*const ucell);
+
+	void cal_v_eff(
+		const Charge*const chg_1,
+		const UnitCell*const ucell,
+		ModuleBase::matrix& v_eff) override;
+
+	const Charge*const chg_0 = nullptr;
+	ModuleBase::matrix v_xc_0;
+};
+
+} // namespace elecstate
+
+#endif