FAR INFRARED SPECTRA OF HALOGENATED PHENOLS. THE CALCULATION OF THE BARRIER HEIGHT OF THE HYDROXY GROUP FROM THE OBSERVED TORSIONAL VIBRATIONS.

Abstract : The far infrared spectra of ortho, meta and para fluoro-, chloro- and bromo-phenol have been observed. In several of these phenol molecules, for the first time the hot bands, i.e., higher transition 1 approaches limit of 2, 2 approaches limit of 3, could be resolved and both the V2 and V4 terms of the potential energy expression could be evaluated. The ratio of V4/V2 ranged from +0.026 to -0.017. Also, rotamers were observed in several of the meta halophenols. A set of Mathieu tables of very large s values used in the calculation of barrier height is given. (Author)