Dielectric, ultrasonic and carbon-13 nuclear magnetic resonance relaxation measurements of t-butyl alcohol–water mixtures

Abstract

Dielectric, ultrasonic and 13C nuclear magnetic resonance relaxation measurements are reported on mixtures of t-butyl alcohol and water over the temperature range 278–308 K. Supporting measurements of the refractive index, density and viscosity are also presented. Deviations from ideal mixing behaviour are observed in the volumes of mixing, permittivities and adiabatic compressibilities of the mixtures. The location of the minima in the excess occurring at different compositions depend upon the method of measurement. Similarly the relaxation behaviour, as observed using different techniques, reveals different aspects of the motion of the molecules in the fluid. The various effects observed are rationalized in terms of a model in which it is assumed that t-butyl alcohol dimers and trimers and various hydrated forms play an important role in determining the structure of these mixtures.