q3::paw_one_center::OnSiteOccupationSymmetrizer Class Reference

#include <occupation_symmetrization.hpp>

Public Member Functions
void	build (const Crystal &crystal_structure, const std::vector< SymmetryOperation > &symmetry_operations, std::vector< ChannelAngularLayout > layout_by_species)
bool	is_active () const
int	number_of_symmetry_operations () const
void	symmetrize (const Crystal &crystal_structure, Matrix< Real > &occupations) const

Detailed Description

The point-group average of ρ_ij, with D^l(R) built once and reused.

Built once per run (the operations and the datasets do not change during an SCF) and applied to every ρ_ij array each iteration. is_active() is false when there is nothing to do — one operation, or no channels — so the caller does not need a second condition of its own.

Definition at line 112 of file occupation_symmetrization.hpp.

Member Function Documentation

build()

void q3::paw_one_center::OnSiteOccupationSymmetrizer::build ( const Crystal &  crystal_structure, const std::vector< SymmetryOperation > &  symmetry_operations, std::vector< ChannelAngularLayout >  layout_by_species  )

inline

Parameters

crystal_structure	supplies the lattice for R_cart and the atom→species map
symmetry_operations	the crystal's operations, atom_map filled in
layout_by_species	one entry per species type, indexed as species_type_index

One D^l per (operation, l): two channels sharing an l share the matrix, and the angular quadrature that builds it is the expensive part.

Definition at line 119 of file occupation_symmetrization.hpp.

References q3::build_real_harmonic_rotation_matrix(), and q3::cartesian_rotation_of().

is_active()

bool q3::paw_one_center::OnSiteOccupationSymmetrizer::is_active ( ) const

inline

Definition at line 162 of file occupation_symmetrization.hpp.

Referenced by symmetrize().

number_of_symmetry_operations()

int q3::paw_one_center::OnSiteOccupationSymmetrizer::number_of_symmetry_operations ( ) const

inline

Definition at line 166 of file occupation_symmetrization.hpp.

symmetrize()

void q3::paw_one_center::OnSiteOccupationSymmetrizer::symmetrize ( const Crystal &  crystal_structure, Matrix< Real > &  occupations  ) const

inline

Replace ρ_ij by its group average, in place.

occupations[atom][i * nh_atom + j], with nh_atom the atom's own channel count — the indexing stride the ultrasoft accumulation writes with, which is not the allocated row length in a mixed-species cell. An atom whose image under some operation could not be identified (an atom_map entry left unresolved) contributes nothing for that operation, and the average is taken over the operations that did contribute: averaging against an array that was never accumulated would be worse than averaging over fewer operations.

(D ᵀ ρ D)_{m m'} = Σ_pq D_{p m} ρ_{pq} D_{q m'}, with p and q running over the partners of first and second — the channels sharing their radial index.

Definition at line 182 of file occupation_symmetrization.hpp.

References is_active(), q3::Crystal::number_of_atoms(), and q3::Crystal::species_type_index().

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The documentation for this class was generated from the following file:

• src/layer_4_computation/paw/one_center/occupation_symmetrization.hpp