VIBRATIONAL DEPHASING AXIAL AND EQUATORIAL CONFORMERS IN CYCLOHEXYL HALIDES

The Raman and IR spectra of the C-X stretching modes (X = Cl, Br, I) i n the axial and the equatorial positions of cyclohexyl halides have be en measured at room temperature. The band broadening mechanisms and th e differences in the rate of vibrational dephasing of the axial and th e equatorial conformers have been discussed. It has been found that in termolecular long-range transition dipole-transition dipole coupling g ives the main contribution to the differences in vibrational dephasing rate. This paper demonstrates that a simultaneous study of the vibrat ional dephasing of different conformers provides a method to isolate t he individual relaxation mechanisms.