Stochastic Generalized Active Space Self-Consistent Field: Theory and Application.

ABSTRACT: An algorithm to perform stochastic generalized active space calculations, Stochastic-GAS, is presented, that uses the Slater determinant based FCIQMC algorithm as configuration interaction eigensolver. Stochastic-GAS allows the construction and stochastic optimization of preselected truncated configuration interaction wave functions, either to reduce the computational costs of large active space wave function optimizations, or to probe the role of specific electron correlation pathways. As for the conventional GAS procedure, the preselection of the truncated wave function is based on the selection of multiple active subspaces while imposing restrictions on the interspace excitations. Both local and cumulative minimum and maximum occupation number constraints are supported by Stochastic-GAS

SUBMITTER: Weser O 

PROVIDER: S-EPMC8757470 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature