iodata.overlap module

Module for computing overlap of atomic orbital basis functions.

class GaussianOverlap(n_max)

Bases: object

Gaussian Overlap Class.

__init__(n_max)

Initialize class.

Parameters

n_max (int) – Maximum angular momentum.

compute_overlap_gaussian_1d(x1, x2, n1, n2, two_at)

Compute overlap integral of two Gaussian functions in one-dimensions.

compute_overlap(obasis, atcoords)

Compute overlap matrix for the given molecular basis set.

\[\braket{\psi_{i}}{\psi_{j}}\]

This function takes into account the requested order of the basis functions in obasis.conventions. Note that only L2 normalized primitives are supported at the moment.

Parameters

• obasis (MolecularBasis) – The orbital basis set.

• atcoords (ndarray) – The atomic Cartesian coordinates (including those of ghost atoms).

Returns

The matrix with overlap integrals, shape=(obasis.nbasis, obasis.nbasis).

Return type

overlap

gob_cart_normalization(alpha, n)

Compute normalization of exponent.

Parameters

• alpha (ndarray) – Gaussian basis exponents

• n (ndarray) – Cartesian subshell angular momenta

Returns

The normalization constant for the gaussian cartesian basis.

Return type

np.ndarray