TY  - JOUR
A1  - Ehlert, Christopher
A1  - Gühr, Markus
A1  - Saalfrank, Peter
T1  - An efficient first principles method for molecular pump-probe NEXAFS spectra
T2  - The journal of chemical physics : bridges a gap between journals of physics and journals of chemistr
N2  - 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.
Y1  - 2018
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/51488
SN  - 0021-9606
SN  - 1089-7690
VL  - 149
IS  - 14
PB  - American Institute of Physics
CY  - Melville
ER  -