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  • Assessing the performance of ΔSCF and the diagonal second-order self-energy approximation for calculating vertical core excitation energies
Title: Assessing the performance of ΔSCF and the diagonal second-order self-energy approximation for calculating vertical core excitation energies
Vertical core excitation energies are obtained using a combination of the ΔSCF method and the diagonal second-order self-energy approximation. These methods are applied to a set of neutral molecules and their anionic forms. An assessment of the results with the inclusion of relativistic effects is presented. For core excitations involving delocalized symmetry orbitals, the applied composite method improves upon the overestimation of ΔSCF by providing approximate values close to experimental K-shell transition energies. The importance of both correlation and relaxation contributions to the vertical core-excited state energies, the concept of local and nonlocal core orbitals, and the consequences of breaking symmetry are discussed.  more » « less
Award ID(s):
1848580 2019144
PAR ID:
10420590
Author(s) / Creator(s):
;
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
157
Issue:
8
ISSN:
0021-9606
Page Range / eLocation ID:
084115
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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