Minimal Active Space: NOSCF and NOSI in Multistate Density Functional Theory.

ABSTRACT: In this Perspective, we introduce a minimal active space (MAS) for the lowest N eigenstates of a molecular system in the framework of multistate density functional theory (MSDFT), consisting of no more than N² nonorthgonal Slater determinants. In comparison with some methods in wave function theory in which one seeks to expand the ever increasing size of an active space to approximate the wave functions, it is possible to have an upper bound in MSDFT because the auxiliary states in a MAS are used to represent the exact N-dimensional matrix density function D(r). Here, we partition the total Hamiltonian matrix functional H[D] into an orbital-dependent part, including multistate kinetic energy T_ms and Coulomb-exchange ene

SUBMITTER: Lu Y 

PROVIDER: S-EPMC12747309 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature