quemb.molbe.lo.MixinLocalize.localize

MixinLocalize.localize(lo_method, iao_valence_basis='sto-3g', iao_loc_method='SO', iao_valence_only=False, pop_method=None, init_guess=None, hstack=False, nosave=False)

Molecular orbital localization

Performs molecular orbital localization computations. For large basis, IAO is recommended augmented with PAO orbitals.

NOTE: For molecular systems, with frozen core, the core and valence are localized TOGETHER. This is not the case of periodic systems.

Parameters:

  • lo_method (str) – Localization method in quantum chemistry. ‘lowdin’, ‘boys’, ‘er’, ‘pm’, and ‘iao’ are supported.

  • iao_valence_basis (str) – Name of minimal basis set for IAO scheme. ‘sto-3g’ suffice for most cases.

  • iao_loc_method (str) – Name of localization method in quantum chemistry for the IAOs and PAOs. Options include ‘Boys’, ‘PM’, ‘ER’ (as documented in PySCF). Default is ‘SO’, or symmetric orthogonalization. If not using SO, we suggest using ‘PM’, as it is more robust than ‘Boys’ localization and less expensive than ‘ER’

  • iao_valence_only (bool) – If this option is set to True, all calculation will be performed in the valence basis in the IAO partitioning. Default is False. This is an experimental feature: the returned energy is not accurate