sc::G12Libint2 Class Reference
G12Libint2 is a specialization of Int2eLibint2 that computes two-electron integrals specific to explicitly correlated methods which use Gaussian geminals. More...
#include <chemistry/qc/libint2/g12.h>
Inheritance diagram for sc::G12Libint2:
Public Member Functions | |
| G12Libint2 (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 IntParamsG12::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 |
Detailed Description
G12Libint2 is a specialization of Int2eLibint2 that computes two-electron integrals specific to explicitly correlated methods which use Gaussian geminals.G12Libint2 can compute integrals with 1 or 2 geminals. 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.
- [g12,[t1,g12']] = -2 exp(g12) * exp(g12') r12^2 G12. Returned as g12t1g12.
- g12[ti,g12'] - g12'[ti,g12] = [ti,G12] * (exp(g12') - exp(g12))/(exp(g12')+exp(g12)). Returned as t1g12 or t2g12.
The documentation for this class was generated from the following files:
- src/lib/chemistry/qc/libint2/g12.h
- src/lib/chemistry/qc/libint2/g12_quartet_data.h