Electronically excited states of chloroethylenes: Experiment and DFT calculations in comparison

• Published in: Journal of electron spectroscopy and related phenomena 2014-08, Vol.195, p.220-229
• Main Author: Khvostenko, O.G.
• Format: Article
• Language: English
• Subjects: Chloroethylenes; DFT calculations; Electron structure; Energy-loss spectroscopy; Negative ions
• ISSN: 0368-2048; 1873-2526
• DOI: 10.1016/j.elspec.2014.07.015

•B3LYP/6-311+G(d,p) calculations of chloroethylenes molecules were performed.•Calculations were correlated with experiment on the molecules ground and excited states.•The general pattern of electron structure of chloroethylenes was obtained.•Necessity of this data for chloroethylenes negative ions study was noted. B3LYP/6-311+G(d,p) calculations of ground and electronically excited states of ethylene, chloroethylene, 1,1-dichloroethylene, 1,2-dichloroethylene-cis, 1,2-dichloroethylene-trans trichloroethylene and tetrachloroethylene molecules have been performed. Molecular orbitals images and orbital correlation diagram are given. The calculation results for chloroethylenes electronically excited states were compared with experimental data from the energy-loss spectra obtained and generally considered previously by C.F. Koerting, K.N. Walzl and A. Kupperman. Several new additional triplet and singlet transitions were pointed out in these spectra considering the calculation results. The finding of the additional transitions was supported by the UV absorption spectrum of trichloroethylene recorded in big cuvette (10cm), where the first three triplet and two low-intensive forbidden singlet transitions were registered. The first triplet of this compound was recorded to be at the same energy as was found with the energy-loss spectroscopy.