Effect of temperature on the hydrogen bond νs band. Part 3.—Liquid phase

Abstract

The frequency of the hydrogen bond ν_s band of the trifluoroethanol–triethylamine complex has a temperature coefficient of +0.1 ± 0.05 cm^–1 K^–1 in the liquid phase. This compares with a zero coefficient for trifluoroethanol–trimethylamine in the vapour, and much larger coefficients reported for systems in which self-association is present. Solvent influence is suggested as the most probable origin of the effect. In contrast, in self-complexed trifluoroethanol, the coefficient is +1.2 ± 0.1 cm^–1 K^–1, and is almost certainly due to temperature variation of the degree of association.