minihf.hamiltonian.integral.nuclear_attraction module

class minihf.hamiltonian.integral.nuclear_attraction.NuclearAttraction

Bases: object

The Obara-Saika scheme for nuclear attraction integral.

contracted(self, cga, cgb)

Evaluate integral over contracted GTOs.

primitive(self, pga, pgb)

Evaluate integral over primitive GTOs.

target(self, r, pga, pgb)

Obtain the target integral in the Obara-Saika recurrence relations.

recurrence(self, r, pga, pgb, pga_1, pga_2, pgb_1)

Run the recurrence.

new_gaussian(self, r, pga, pgb):

Generate all the new primitive GTOs in the Obara-Saika recurrence relations.

contracted(cga, cgb, mol)

Evaluate integral over contracted GTOs.

Parameters:

• cga (ContractedGaussian) – The first contracted gaussian orbital.

• cgb (ContractedGaussian) – The second contracted gaussian orbital.

• mol (Molecule) – The instance of Molecule class.

Returns:

result – Integral value.

Return type:

float

primitive(pga, pgb, C)

Evaluate integral over primitive gaussian orbitals.

Parameters:

• pga (PrimitiveGaussian) – The first primitive gaussian orbital.

• pgb (PrimitiveGaussian) – The second primitive gaussian orbital.

• C (list) – The coordinates of the center of the molecule.

Returns:

result – Integral value.

Return type:

float

target(N, shell_a, shell_b)

Obtain the target integral using shell tuples instead of objects.

recurrence(r, N, shell_a, shell_b)

Run recurrence without creating new Gaussian objects.

recurrence_swapped(r, N, shell_a, shell_b)

Recurrence with swapped roles (when pgb has angular momentum).