When do structural anomalies of ionic crystals begin

This paper describes a joint correlation analysis of the heat capacity Cp(T) and volume thermal expansivity β(T) of potassium chloride (KCl) over the entire temperature range of its solid state (from absolute zero to Tm) A trilinear model for the β(Cp) correlation dependence, consistent with experimental data and consisting of three smoothly joined linear segments, has been constructed The differential Gruneisen parameter γ ' ~ ∂β/∂Cp, convenient for describing such behavior, has three characteristic steps Analysis of data in this model has made it possible to tabulate thermodynamic and thermal expansion data for solid KCl, in good agreement with the most reliable experimental data

Joint Analysis of the Heat Capacity and Thermal Expansion of Solid Potassium Chloride

From comparison of results of measurements of the coefficients of thermal expansion of the alkali halides using X-ray diffraction methods and dilatometer and interferometer methods, it is claimed that the nonlinearity of the thermal expansion is due to anharmonic effects and not to defect formation.

J. L. Lawrence

Papers

Thermal expansion of the alkali halides