Theoretical Conformational Studies of Thiol and Thione Forms of Thioacetic Acid

Year 2012, Volume: 25 Issue: 2, 343 - 354, 16.04.2012

Cemil Ogretır Müjgan Ozkutuk

Abstract

The theoretical conformational structure analyses were performed using density functional theory for thiol and thione tautomeric forms of thioacetic acid (TAA). At the B3LYP/6-311++G(d,p) level, thiol [CH3(C=O)SH] and thione [CH3(C=S)OH] were found more stable than anti forms and the energy differences between these two forms were computed to be ca. 6.7 kJ mol−1 and ca. 27 kJ mol−1, respectively. Barrier energies for thiol and thione forms of thioacetic acid were calculated by using the density functional theory [DFT(B3LYP)/6-311++G(d,p)] method contributing to more than 90% of the population in gas phase at room temperature and also reported a theoretical study on vibrational spectra of thiol and thione tautomeric forms of thioacetic acid obtained by the density functional theory.

 

 

                  Key Words: thioacetic acid, DFT calculations,

                  tautomerisation, PES, IR spectroscopy.

 

Keywords

thioacetic acid, DFT calculations, tautomerisation, PES, IR spectroscopy

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