Heat capacities of PbI2, ZnCl2, and AsI3 have been determined by adiabatic shield calorimetry from T = 5 K to T = 350 K. No anomalous regions were found in the heat capacity of PbI2 and ZnCl2. Two anomalous regions were found in the heat capacity of AsI3 : one small sharp peak at T = 161 K, and the other, a broad region from about T = 225 K to T = 290 K. The thermodynamic properties have been evaluated and the values of molar heat capacity, entropy, and enthalpy at T = 298.15 K were found to be : [GRAPHICS]