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Title: Occupied-Virtual Orbitals for Chemical Valence with Applications to Charge Transfer in Energy Decomposition Analysis
In this article, we introduce the occupied-virtual orbitals for chemical valence (OVOCV). The OVOCVs can replace or complement the closely related idea of the natural orbitals for chemical valence (NOCV). The input is a difference density matrix connecting any initial single determinant to any final determinant, at a given molecular geometry, and a given one-particle basis. This arises in problems such as orbital rearrangement or charge-transfer in energy decomposition analysis. The OVOCVs block-diagonalize the density difference operator into 2 × 2 blocks which are spanned by one level that is filled in the initial state (the occupied OVOCV) and one which is empty (the virtual OVOCV). By contrast, the NOCVs fully diagonalize the density difference matrix, and therefore are orbitals with mixed occupied-virtual character. Use of the OVOCVs makes it much easier to identify the donor and acceptor orbitals. We also introduce two different types of energy decomposition analysis (EDA) methods with the OVOCVs, and most importantly, a charge decomposition analysis (CDA) method that fixes the unreasonably large charge transfer amount obtained directly from NOCV analysis.  more » « less
Award ID(s):
2313791
PAR ID:
10633069
Author(s) / Creator(s):
;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
The Journal of Physical Chemistry A
Volume:
128
Issue:
26
ISSN:
1089-5639
Page Range / eLocation ID:
5202 to 5211
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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