Heat Capacity and Standard Thermodynamic Functions of the Wulfenite PbMoO4 over the Temperature Range of (0 to 320) K

The heat capacity of natural lead molybdate (wulfenite, PbMoO4) has been measured by the method of vacuum adiabatic calorimetry over the temperature range of (4.3 to 80) K, and its thermodynamic functions in the range from (0 to 320) K have been calculated. The obtained standard values are as follows: Cpo(298.15) = (119.4 ± 0.13) J·mol−1·K−1, S°(298.15) = (161.5 ± 0.3) J·mol−1·K−1, and ΔH°(298.15) = (23018 ± 23) J·mol−1. The experimental data have been compared with the calculated values of the heat capacity obtained previously by different methods. The greatest correspondence of the thermodynamic functions has been obtained when employing the method of interatomic potentials using the computer program LADY.