An efficient first principles method for molecular pump-probe NEXAFS spectra
- Pump-probe near edge X-ray absorption fine structure (PP-NEXAFS) spectra of molecules offer insight into valence-excited states, even if optically dark. In PP-NEXAFS spectroscopy, the molecule is "pumped" by UV or visible light enforcing a valence excitation, followed by an X-ray "probe" exciting core electrons into (now) partially empty valence orbitals. Calculations of PP-NEXAFS have so far been done by costly, correlated wavefunction methods which are not easily applicable to medium-sized or large molecules. Here we propose an efficient, first principles method based on density functional theory in combination with the transition potential and Delta SCF methodology (TP-DFT/Delta SCF) to compute molecular ground state and PP-NEXAFS spectra. We apply the method to n ->pi* pump/O-K-edge NEXAFS probe spectroscopy of thymine (for which both experimental and other theoretical data exist) and to n -> pi* or pi -> pi* pump/N-K-edge NEXAFS probe spectroscopies of trans-and cis-azobenzene. Published by AIP Publishing.
Author details: | Christopher EhlertORCiDGND, Markus GührORCiDGND, Peter SaalfrankORCiDGND |
---|---|
DOI: | https://doi.org/10.1063/1.5050488 |
ISSN: | 0021-9606 |
ISSN: | 1089-7690 |
Pubmed ID: | https://pubmed.ncbi.nlm.nih.gov/30316280 |
Title of parent work (English): | The journal of chemical physics : bridges a gap between journals of physics and journals of chemistr |
Subtitle (English): | application to thymine and azobenzene |
Publisher: | American Institute of Physics |
Place of publishing: | Melville |
Publication type: | Article |
Language: | English |
Date of first publication: | 2018/10/11 |
Publication year: | 2018 |
Release date: | 2021/09/01 |
Volume: | 149 |
Issue: | 14 |
Number of pages: | 13 |
Funding institution: | DFG (German Research Council) through the Cluster of Excellence "Unifying Concepts in Catalysis" [304]; SOSCIP Consortium (TalentEdge program); Lichtenberg professorship of the Volkswagen foundation |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physik und Astronomie |
Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie | |
5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften | |
Peer review: | Referiert |