Computational studies of 1,2-dithiete and dithioglyoxal

✍ Scribed by John D. Goddard

• Book ID: 102881022
• Publisher: John Wiley and Sons
• Year: 1987
• Tongue: English
• Weight: 669 KB
• Volume: 8
• Category: Article
• ISSN: 0192-8651
• DOI: 10.1002/jcc.540080416

✦ Synopsis

Ab initio calculations are reported on the energies, geometries, vibrational frequencies, and ionization potentials of the HzCzSz isomers: 1,2-dithiete, cis-dithioglyoxal, and trans-dithioglyoxal. In contrast to most earlier computations, the results of this work indicate that 1,a-dithiete and cis-dithioglyoxal lie close in energy (within 3 kcal/mol) with the dithial more stable. Trans-dithioglyoxal is found to be 4.1 kcal/mol more stable than the cis isomer and faces a barrier to internal rotation of 5.5 kcal/mol. The predicted rotational constants for 1,a-dithiete agree within -0.05 GHz with the experimentally observed values thus lending credence to the predictions for cis-dithioglyoxal (A, 14.30683, Be 2.46324, C, 2.10143 GHz). Vibrational frequencies are given as potential aids to the identification of these molecules. 6-31G* ASCF calculations predict that at low energies (8 to 13 eV) the photoelectron spectra of l,%-dithiete, cis-dithioglyoxal and trans-dithioglyoxal should be similar.