Multiconfigurational Pair-Density Functional Theory Is More Complex than You May Think.

ABSTRACT: Multiconfigurational pair-density functional theory (MC-PDFT) is a promising way to describe both strong and dynamic correlations in an inexpensive way. The functionals in MC-PDFT are often "translated" from standard spin density functionals. However, these translated functionals can in principle lead to "translated spin densities" with a nonzero imaginary component. Current developments so far neglect this imaginary part by simply setting it to zero. In this work, we show how this imaginary component is actually needed to reproduce the correct physical behavior in a range of cases, especially low-spin open shells. We showcase the resulting formalism on both local density approximation and generalized gradient approximation functionals and illustrate the numerical behavior by benchmarking

SUBMITTER: Rodrigues GLS 

PROVIDER: S-EPMC10641845 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature