quemb.molbe.mbe.BE.__init__

BE.__init__(mf, fobj, eri_file='eri_file.h5', lo_method='lowdin', iao_loc_method='SO', pop_method=None, compute_hf=True, restart=False, restart_file='storebe.pk', nproc=1, ompnum=4, thr_bath=1e-10, scratch_dir=None, int_transform='in-core', auxbasis=None)

Constructor for BE object.

Parameters:

  • mf (SCF) – PySCF mean-field object.

  • fobj (FragPart) – Fragment object containing sites, centers, edges, and indices.

  • eri_file (str | PathLike) – Path to the file storing two-electron integrals.

  • lo_method (str) – Method for orbital localization, by default ‘lowdin’.

  • iao_loc_method (str | None) – Method for IAO localization, by default “SO”

  • pop_method (str | None) – Method for calculating orbital population, by default ‘meta-lowdin’ See pyscf.lo for more details and options

  • compute_hf (bool) – Whether to compute Hartree-Fock energy, by default True.

  • restart (bool) – Whether to restart from a previous calculation, by default False.

  • restart_file (str | PathLike) – Path to the file storing restart information, by default ‘storebe.pk’.

  • nproc (int) – Number of processors for parallel calculations, by default 1. If set to >1, threaded parallel computation is invoked.

  • ompnum (int) – Number of OpenMP threads, by default 4.

  • thr_bath (float,) – Threshold for bath orbitals in Schmidt decomposition

  • scratch_dir (WorkDir | None) – Scratch directory.

  • int_transform (Literal['in-core', 'out-core-DF', 'int-direct-DF', 'sparse-DF']) –

    The possible integral transformations.

    • "in-core" (default): Use a dense representation of integrals in memory without density fitting (DF) and transform in-memory.

    • "out-core-DF": Use a dense, DF representation of integrals, the DF integrals \((\mu, \nu | P)\) are stored on disc.

    • "int-direct-DF": Use a dense, DF representation of integrals, the required DF integrals \((\mu, \nu | P)\) are computed and fitted on-demand for each fragment.

    • "sparse-DF": Work in progress. Use a sparse, DF representation of integrals, and avoid recomputation of elements that are shared across fragments.

  • auxbasis (str | None) – Auxiliary basis for density fitting, by default None (uses default auxiliary basis defined in PySCF). Only relevant for int_transform in {"int-direct-DF", "sparse-DF"}.