High-pressure differential scanning calorimetry (DSC) investigations at low temperatures: solid-solid and solid-liquid phase transformations of some molecular crystals up to 1750 bar

Abstract

With a high-pressure low-temperature differential scanning calorimeter (dsc) developed by Arntz, phase transition temperatures and enthalpies along the transition lines were measured for the molecular crystals t-butyl bromide (2-bromo-2-methyl-propane), norbornadiene (bicyclo[2.2.1.]hept-2,5-diene), cyclohexane and cyclohexylcyclohexane (1,1'-bicyclohexyl). The experimental range extended from about 80 to 340 K and from normal pressure up to 1750 bar. From these data other thermodynamic quantities can be calculated such as phase transition entropies and volumes.