ChemBasisSets

This package constructs atomic orbital (AO) basis functions using Polynomials4ML and verifies them against PySCF.

The AO basis functions take the form of a linear combination of primitive GTOs:

[ \phi_{lm}(\mathbf{r}) = Y_{lm}(\hat{\mathbf{r}}) \sum_{i=1}^{N} \xi_i , r^l e^{-\alpha_i r^2} ]

Both ( \alpha_i ) and ( \xi_i ) are extracted from the PySCF package.

AO Basis Construction

The function build_ao(atom::String, basis::String) constructs an AO basis compatible with PySCF.

Example

using ChemBasisSets

atom = "Be"
basis_set = "cc-pvdz"
basis = build_ao(atom, basis_set)

Saving & Reloading AO Basis

To avoid repeated PySCF calls, one can save all AO basis data to a JSON file and load it later.

Save Basis

save_all_bases_to_json(["Be"], ["cc-pvdz"], "ao_basis.json")

Load Basis

With this .json file, PySCF is no longer needed.
All basis sets can be precomputed and stored for lookup when needed.

basis = load_basis_from_json("ao_basis.json", "Be", "cc-pvdz")