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Strongly separated pairs of core electrons in computed ground states of small molecules.

ABSTRACT: We have performed full configuration interaction computations of the ground states of the molecules Be, BeH₂, Li, LiH, B, and BH and verified that the core electrons constitute "separated electron pairs." These separated pairs of core electrons have nontrivial structure; the core pair does not simply occupy a single spatial orbital. Our method of establishing the presence of separated electron pairs is direct and conclusive. We do not fit a separated pair model; we work with the wavefunctions of interest directly. To establish that a given group of spin-orbitals contains a quasi-separated pair, we verify by direct computation that the quantum state of the electrons that occupy those spin-orbitals is nearly a pure 2-electron state.

SUBMITTER: Gottlieb AD

PROVIDER: S-EPMC3564454 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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Strongly separated pairs of core electrons in computed ground states of small molecules.

Gottlieb Alex D AD Weishäupl Rada M RM

Computational & theoretical chemistry 20130301 C

We have performed full configuration interaction computations of the ground states of the molecules Be, BeH<sub>2</sub>, Li, LiH, B, and BH and verified that the core electrons constitute "separated electron pairs." These separated pairs of core electrons have nontrivial structure; the core pair does not simply occupy a single spatial orbital. Our method of establishing the presence of separated electron pairs is direct and conclusive. We do not fit a separated pair model; we work with the wavef ...[more]

PMID: 23459686

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