Low-Temperature Heat Capacity of M-Type Terbium Orthotantalate and Schottky Anomaly

The molar heat capacity of М-type terbium orthotantalate was measured by adiabatic calorimetry in the range 18–346 K. Smoothed heat capacity values were used to calculate the entropy, enthalpy gain, and reduced Gibbs free energy. The Schottky anomalous heat capacity in lanthanide compounds and its evaluation methods were analyzed.