1. X-ray photoelectron and NEXAFS spectroscopy of thionated uracils in the gas phase.
- Author
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Mayer, Dennis, Handrich, Max, Picconi, David, Lever, Fabiano, Mehner, Lisa, Murillo-Sanchez, Marta L., Walz, Constantin, Titov, Evgenii, Bozek, John, Saalfrank, Peter, and Gühr, Markus
- Subjects
X-ray absorption near edge structure ,X-ray photoelectron spectra ,X-ray photoelectron spectroscopy ,COUPLED-cluster theory ,X-ray absorption - Abstract
We present a comprehensive, combined experimental and theoretical study of the core-level photoelectron and near-edge x-ray absorption fine structure (NEXAFS) spectra of 2-thiouracil, 4-thiouracil, and 2,4-dithiouracil at the oxygen 1s, nitrogen 1s, carbon 1s, and the sulfur 2s and 2p edges. X-ray photoelectron spectra were calculated using equation-of-motion coupled-cluster theory (EOM-CCSD), and NEXAFS spectra were calculated using algebraic diagrammatic construction and EOM-CCSD. For the main peaks at O and N 1s as well as the S 2s edge, we find a single photoline. The S 2p spectra show a spin–orbit splitting of 1.2 eV with an asymmetric vibrational line shape. We also resolve the correlation satellites of these photolines. For the carbon 1s photoelectrons, we observe a splitting on the eV scale, which we can unanimously attribute to specific sites. In the NEXAFS spectra, we see very isolated pre-edge features at the oxygen 1s edge; the nitrogen edge, however, is very complex, in contrast to the XPS findings. The C 1s edge NEXAFS spectrum shows site-specific splitting. The sulfur 2s and 2p spectra are dominated by two strong pre-edge transitions. The S 2p spectra show again the spin–orbit splitting of 1.2 eV. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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