Class LCAO_Descriptor

Class Documentation

class LCAO_Descriptor

This class computes the descriptors for each atom from LCAO basis set, interfaces with pytorch to obtain the correction potential in LCAO basis, and computes the forces according to the correction potential.

For details of DeePKS method, you can refer to DeePKS paper.

Public Functions

explicit LCAO_Descriptor()
~LCAO_Descriptor()
void init(const int lm, const int nm, const int tot_inl)

only for descriptor part, not including scf

Parameters

  • lm – max angular momentum quantum number: ‘L’

  • nm – max orbital number with the same ‘L’, for each ‘L’

  • tot_inl – total number of radial orbitals (sum of atoms ‘I’, angular number ‘L’ and orbital number ‘N’)

void build_S_descriptor(const bool &calc_deri)

calculate \(S_{\alpha, \mu} = \langle\alpha|\phi_\mu\rangle \) overlap between lcao basis Phi and descriptor basis Alpha

Parameters

calc_deri – 0 for \(\langle\phi|\alpha\rangle\), 1 for \(\langle\frac{d\phi}{dR}|\alpha\rangle\)

void deepks_pre_scf(const std::string &model_file)

  1. Load DeePKS model

  2. Initialize the deltaV Hamiltonian matrix

  3. If FORCE, initialize the matrces for force

Parameters

model_file – path of a traced model file, provided by deepks-kit

void cal_projected_DM(const ModuleBase::matrix &dm)

calculate projected density matrix:

\[D^ I_{ nlmm'} = \sum_{i}\sum_{\mu, \nu}\langle\alpha^I_{nlm}|\phi_\mu\rangle c_{i,\mu}c_{i,\nu} \langle\phi_\nu|\alpha^I_{nlm' }\rangle\]

Parameters

dm – density matrix

void cal_descriptor(void)

EIGENVALUE of pdm in block of I_n_l.

void cal_dm_as_descriptor(const ModuleBase::matrix &dm)

compute the descriptor for each atom

Parameters

dm – density matrix

void cal_gedm(const ModuleBase::matrix &dm)

calculate \(\frac{dE_\delta}{dD^I_{nlmm'}}\)

Parameters

dm – density matrix

void build_v_delta_alpha(const bool &cal_deri)

calculate \(\sum_{I}\sum_{nlmm'}\langle\phi_\mu|\alpha^I_{nlm}\rangle{\frac{dE}{dD^I_{nlmm'}}}\langle\alpha^I_{nlm'}|\phi_\nu\rangle\) (for gamma_only)

Parameters

cal_deri – 0 for 3-center intergration, 1 for its derivation

void build_v_delta_mu(const bool &cal_deri)

calculate \(\sum_{I}\sum_{nlmm'}\langle\phi_\mu|\alpha^I_{nlm}\rangle{\frac{dE}{dD^I_{nlmm'}}}\langle\alpha^I_{nlm'}|\phi_\nu\rangle\) (for multi-k)

Parameters

cal_deri – 0 for 3-center intergration, 1 for its derivation

void cal_v_delta(const ModuleBase::matrix &dm)

compute \(H_{\delta, \mu\nu} = \langle\phi_\mu|V_\delta|\phi_\nu\rangle\)

Parameters

dm – density matrix

void add_v_delta(void)

add \(H_{\delta, \mu\nu}\) to the Hamiltonian matrix

void cal_f_delta_hf(const ModuleBase::matrix &dm)

compute Hellmann-Feynman term of the force contribution of \(E_\delta\)

Parameters

dm – density matrix

void cal_f_delta_pulay(const ModuleBase::matrix &dm)

compute Pulay term of the force contribution of \(E_\delta\)

Parameters

dm – density matrix

void cal_f_delta(const ModuleBase::matrix &dm)

compute the force contribution of \(E_\delta\)

Parameters

dm – density matrix

void print_descriptor(void)

print descriptors based on LCAO basis

void print_H_V_delta(void)

print the \(H_\delta\) matrix in LCAO basis

void print_F_delta(const std::string &fname)

print the force related to \(V_\delta\) for each atom

Parameters

fname – the name of output file

void save_npy_d(void)

The following 3 functions save the [dm_eig], [e_base], [f_base] of current configuration as .npy file, when deepks_scf = 1. After a full group of consfigurations are calculated, we need a python script to load and torch.cat these .npy files, and get l_e_delta,npy and l_f_delta.npy corresponding to the exact E, F data.

Unit of energy: Ry

Unit of force: Ry/Bohr

void save_npy_e(const double &ebase)
Parameters

ebase – \(E_{base}\), ‘en.etot’, in Ry

void save_npy_f(const ModuleBase::matrix &fbase)
Parameters

fbase – \(F_{base}\), in Ry/Bohr

void cal_e_delta_band(const std::vector<ModuleBase::matrix> &dm)

calculate \(tr(\rho H_\delta), \rho = \sum_i{c_{i, \mu}c_{i,\nu}} \) (for gamma_only)

Parameters

dm – density matrix

Public Members

double E_delta = 0.0

(Unit: Ry) Correction energy provided by NN

double e_delta_band = 0.0

(Unit: Ry) \(tr(\rho H_\delta), \rho = \sum_i{c_{i, \mu}c_{i,\nu}} \) (for gamma_only)

double *H_V_delta

Correction term to the Hamiltonian matrix: \(\langle\psi|V_\delta|\psi\rangle\).

ModuleBase::matrix F_delta

(Unit: Ry/Bohr) Total Force due to the DeePKS correction term \(E_{\delta}\)