Chemistry Publications
Document Type
Article
Publication Date
2020
Journal
Journal of Chemical Theory and Computation
Volume
16
Issue
11
First Page
6886
Last Page
6893
URL with Digital Object Identifier
https://doi.org/10.1021/acs.jctc.0c00806
Abstract
The first vertical ionization energy of an atom or molecule is encoded in the rate of exponential decay of the exact natural orbitals. For natural orbitals represented in terms of Gaussian basis functions, this property does not hold even approximately. We show that it is nevertheless possible to deduce the first ionization energy from the long-range behavior of Gaussian-basis-set wavefunc- tions by evaluating the asymptotic limit of a quantity called the average local electron energy (ALEE), provided that the most diffuse functions of the basis set have suitable shape and location. The ALEE method exposes subtle qualitative differences between seemingly analogous Gaussian basis sets and complements the extended Koopmans theorem by being robust in situations where the one-electron reduced density matrix is ill-conditioned.
Notes
This document is the unedited Author’s version of a Submitted Work that was subsequently accepted for publication in Journal of Chemical Theory and Computation, copyright © American Chemical Society after peer review. To access the final edited and published work see https://doi.org/10.1021/acs.jctc.0c00806