sc::GenG12Libint2 Class Reference

GenG12Libint2 is a specialization of Int2eLibint2 that computes two-electron integrals specific to explicitly correlated methods which use general Gaussian geminals (i.e. More...

#include <chemistry/qc/libint2/geng12.h>

Inheritance diagram for sc::GenG12Libint2:

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List of all members.

Public Member Functions
	GenG12Libint2 (Integral *, const Ref< GaussianBasisSet > &, const Ref< GaussianBasisSet > &, const Ref< GaussianBasisSet > &, const Ref< GaussianBasisSet > &, size_t storage, const ContractedGeminal &gbra, const ContractedGeminal &gket)
	When integrals with 1 geminal are needed, gket should be IntParamsGenG12::null_geminal.
double *	buffer (unsigned int t) const
	Returns the location of the buffer with target integrals.
void	compute_quartet (int *, int *, int *, int *)
	Evaluate the target quartet of integrals.
Static Public Member Functions
static size_t	storage_required (const Ref< GaussianBasisSet > &b1, const Ref< GaussianBasisSet > &b2=0, const Ref< GaussianBasisSet > &b3=0, const Ref< GaussianBasisSet > &b4=0)
Classes
class	ExpensiveMath

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Detailed Description

GenG12Libint2 is a specialization of Int2eLibint2 that computes two-electron integrals specific to explicitly correlated methods which use general Gaussian geminals (i.e.

exp(-a*(r1+r2)-g*r12)).

GenG12Libint2 can compute integrals with one general geminals, both in bra and ket, or in bra only. All 2-geminal integrals can be represented as 1-geminals integrals of a product of the original 2 geminals. For example, overlap of 2 geminals (g12*g12') is directly reduced to an integral over 1 geminal (G12) whose exponent is a sum of exponents of g12 and g12'. The following integrals over 2 geminals are needed:

• g12*g12' = G12. Returned as r12_0_g12.
• . Returned as g12t1g12.

[t1,g12] integrals are also needed when bra and ket are not identical. Hence the constructor will throw if bra!=ket.

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

• src/lib/chemistry/qc/libint2/geng12.h
• src/lib/chemistry/qc/libint2/geng12_quartet_data.h