Dielectric studies of hydrogen bonded polar binary mixtures of methanol with ketones and nitriles: A comparison with conformational analysis

Dielectric studies of the binary mixtures of methanol + ketone (acetone and 2,butanone) and methanol + nitrile (acetonitrile and acrylonitrile) were studied on both the pure systems as well as their dilute solutions in benzene. Measurements were made at 300 kHz, three microwave frequencies (5.70 GHz, 9.70 GHz and 32.97 GHz) and at optical frequency. The relaxation times of the binary systems and their dilute solutions in benzene were determined. The dipole moments of the pure systems were determined, both experimentally and from ab-initio calculations. The dipole moments of the binary systems were also determined experimentally. The observed dipole moments are interpreted with respect to the circular ring-like conformers of the binary systems obtained from previous ab-initio calculations of the present authors. The possibility of molecular relaxation time and group relaxation time for the binary systems and their dilution in benzene are also discussed.