Photoabsorption spectroscopy of dimethyl sulfoxide at the O1s, C1s, S2s, and S2p Regions: A comparison with acetone

The S2p, S2s, C1s, and O1s Total Ion Yield (TIY) spectra of gaseous dimethyl sulfoxide (DMSO) and the C1s and O1s TIY spectra of acetone were measured using tunable synchrotron radiation. To establish a complete and accurate spectral analysis, the assignments for the main experimental bands were carried out using density functional theory (DFT) calculations based on half core hole (HCH) method, as implemented in the StoBe‐deMon program, and ab initio calculations, based on the improved virtual orbital (IVO) method, as implemented in the GSCF3 program, using Hartree‐Fock. The hole state was calculated in Huzinaga basis sets for the IVO method and IGLO‐III basis sets for the HCH method. A nonlocal BE88‐PD86 DFT method was used. The geometric parameters were calculated using the DFT‐B3LYP method with the 6‐311+G** basis sets. The experimental and theoretical results for the ionization potentials and the threshold energies are quite similar. The results reflect some differences for both molecules, likely caused by the presence of the S=O (Cs symmetry) as well as the C=O (C2v symmetry) groups. © 2012 Wiley Periodicals, Inc. The core excitation (K and L edges) of Dimethyl Sulfoxide (DMSO) and acetone using ab initio and density functional theory calculations and synchrotron radiation have been studied. The experimental and theoretical results reveal the influence of the replacement of the carbon atom in acetone by the sulfur atom in DMSO, confirmed by the spectra assignments.