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

2012/05/14 by Alex D. Gottlieb, Gottlieb, Alex D., Rada M. Weishaeupl +1
Physics and Astronomy · #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Quantum Physics (quant-ph) #physics.chem-ph #quant-ph

paper · pdf · doi:10.48550/arxiv.1205.2970

To appear in Computational and Theoretical Chemistry

arxiv created 2012/11/21 · arxiv updated 2012/11/22

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.

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