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Title: The Auger spectrum of benzene
We present an ab initio computational study of the Auger electron spectrum of benzene. Auger electron spectroscopy exploits the Auger–Meitner effect, and although it is established as an analytic technique, the theoretical modeling of molecular Auger spectra from first principles remains challenging. Here, we use coupled-cluster theory and equation-of-motion coupled-cluster theory combined with two approaches to describe the decaying nature of core-ionized states: (i) Feshbach–Fano resonance theory and (ii) the method of complex basis functions. The spectra computed with these two approaches are in excellent agreement with each other and also agree well with experimental Auger spectra of benzene. The Auger spectrum of benzene features two well-resolved peaks at Auger electron energies above 260 eV, which correspond to final states with two electrons removed from the 1 e 1 g and 3 e 2 g highest occupied molecular orbitals. At lower Auger electron energies, the spectrum is less well resolved, and the peaks comprise multiple final states of the benzene dication. In line with theoretical considerations, singlet decay channels contribute more to the total Auger intensity than the corresponding triplet decay channels.  more » « less
Award ID(s):
2154482 1856342
PAR ID:
10420485
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
158
Issue:
6
ISSN:
0021-9606
Page Range / eLocation ID:
064109
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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