Naslov
Core–shell excitation of isoxazole at the C, N, and O K-edges – an experimental NEXAFS and theoretical TD-DFT study

Autori
Wasowicz, Tomasz J. ; Ljubić, Ivan ; Kivimäki, Antti ; Richter, Robert

Izvornik
PCCP. Physical chemistry chemical physics (1463-9076) 24 (2022); 19302-19313

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Isoxazole ; Core Electron Spectroscopy ; X-ray Photoelectron Spectroscopy ; Near Edge X-ray Absorption Fine Structure Spectroscopy (NEXAFS) ; Density Functional Theory ; Time-dependent Density Functional Theory

Sažetak
The near-edge X-ray absorption fine structure (NEXAFS) spectra of the gas-phase isoxazole molecule have been measured by collecting total ion yields at the C, N, and O K-edges. The spectral structures have been interpreted using time-dependent density functional theory (TD-DFT) with the short-range corrected SRC2-BLYP exchange– correlation functional. Experimental and calculated energies of core excitations are generally in good agreement, and the nature of observed core-excitation transitions has been elucidated. The experimental C 1s, N 1s, and O 1s core electron binding energies (CEBEs) have additionally been estimated from another yield measurement where the neutral fragments in high- Rydberg (HR) states were ionized by the electric field. For comparison, theoretical CEBEs have been calculated at the ΔM06-2X//mixed basis set level. We have also calculated the vibrationally resolved spectra pertaining to the lowest C 1s and N 1s core-excited roots in the Franck–Condon–Herzberg– Teller (FCHT) approximation. These spectra correlate well with the observed spectral features and have proven useful in resolving certain ambiguities in the assignment of the low-lying C 1s NEXAFS bands.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Kemija

POVEZANOST RADA