Coulomb_Matrix_Elements_Calculator Class Reference

Collaboration diagram for Coulomb_Matrix_Elements_Calculator:

Public Member Functions
void	add_longrange (const Atom_List &atlist, const Distribute_EV_List &EV_e, const Distribute_EV_List &EV_h, int nr_e, int nr_h, double epsilon, int nrblocks, int verbosity=1)
void	add_onsite (const Atom_List &atlist, const Coulomb_Onsite_Storage_List &onsite_storage_list, const Distribute_EV_List &EV_e, const Distribute_EV_List &EV_h, int nr_e, int nr_h, double epsilon, int verbosity=1)
void	MPI_Reduce_to_Node0 ()
	Add parts calculated on different nodes and move them to node 0.
	Coulomb_Matrix_Elements_Calculator (Coulomb_Matrix_Elements::Type type, int nr_e, int nr_h)

Public Attributes
Coulomb_Matrix_Elements	mat_elem

Member Function Documentation

void Coulomb_Matrix_Elements_Calculator::add_longrange	(	const Atom_List &	atlist,
		const Distribute_EV_List &	EV_e,
		const Distribute_EV_List &	EV_h,
		int	nr_e,
		int	nr_h,
		double	epsilon,
		int	nrblocks,
		int	verbosity = 1
	)

LONGRANGE PART: Calculation of the longrange part requires taking the matrix product

Vijkl=(sum_m phi^*_{im} phi_{lm})^T U (sum_m phi^*_{jm} phi_{km}) Phi_{r,{ij}}=(sum_m phi^*_{im} phi_{jm})

Main problem: storage of all eigenvector data at each process Solution: Distribute Eigenvectors according to atom numbers across processes Also: further decompose nr. of local atoms into blocks to reduce memory for U

• read and distribute eigenvectors
• loop through blocks for Phi_2 (decompose local atoms):
  • calculate local part of Phi_2
  • loop through blocks for Phi_1 (decompose local atoms):
    • ask subsequently for local parts of Phi_1 from processes 0,1,2,...
    • calculate U
    • calculate contribution to Phi_1*U*Phi_2 and add to coulomb_storage
• Finally, sum up all contributions from all processes

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

• /home/moritz/QNANO_PRODUCTION/qnano_new/include/coulomb/Coulomb_Matrix_Elements_Calculator.h
• /home/moritz/QNANO_PRODUCTION/qnano_new/sources/coulomb/Coulomb_Matrix_Elements_Calculator.cc