15min:
SH-STRETCHING INTENSITIES AND INTRAMOLECULAR HYDROGEN BONDING IN ALKANETHIOLS.

B. J. MILLER, J. R. LANE, A. H. SODERGREN, H. G. KJAERGAARD, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand; M. E. DUNN AND V. VAIDA, Department of Chemistry and Biochemistry and CIRES, University of Colorado, Campus Box 215, Boulder, CO 80309.

The SH-stretching overtone transitions of tert-butylthiol and ethanethiol are observed using FT-IR, NIR and photoacoustic spectroscopies. The intensities of these are compared with OH-stretching overtones from the corresponding alcohols. We explain the paucity of SH-stretching intensity using an anharmonic oscillator local mode model. SH- and OH-stretching overtone spectra of 1,2-ethanedithiol and 2-mercaptoethanol are recorded to observe the different effects that hydrogen bonding involving SH - - - S, SH - - - O and OH - - - S have on the spectra. We discuss these effects with the help of high level ab initio calculations.