Heat capacities of HfB2.035 and HfC0.968 from 5 to 350 K

Abstract

Heat capacities were determined by adiabatic calorimetry on well-characterized samples of HfB2.035 and HfC0.968. The results are simply sigmoid except for a peak in the first derivative of the HfB2 smoothed results (not characteristic of our ZrB2 or NbB1.963 data) near 110 K possibly occasioned by a Schottky anomaly due to crystal field effects. At 298.15 K the heat capacity Cp, entropy increment {So)(T) - So(0)}, and function {Go(T) - Ho(0)}/T for HfB2.035 are 11.90, 10.25, and -4.323 calth K-1 mol-1. Those for HfC0.968 are 8.931, 9.407, and -4.311 calth K-1 mol-1.