High temperature enthalpy, heat capacity and other thermodynamic functions of solid InN Original Research Article

The heat capacity and the heat content of indium nitride were measured by Calvet calorimetry (305–390 K) and by drop calorimetry (427–774 K). The temperature dependence of the heat capacity in the form Cpm=43.886+8.194×10−3T−1.007×106T−2+8.353×107T−3(J K−1 mol−1) was derived by the least squares method from the experimental data. Furthermore, the standard molar entropy S0m (298 K)=42.51 J K−1 mol−1 was assessed taking into account the recently reported phonon density of states, low temperature Cpm and the current data. Thermodynamic functions calculated on the basis of our results and literature data on the heat of formation of InN are given.