High temperature enthalpy and heat capacity of GaN

The heat capacity and the heat content of gallium nitride were measured by calvet calorimetry (320–570 K) and by drop calorimetry (670–1270 K), respectively. The temperature dependence of the heat capacity in the form Cpm=49.552+5.440×10−3T−2.190×106T−2+2.460×108T−3 was derived by the least squares method. Furthermore, thermodynamic functions calculated on the basis of our experimental results and literature data on the molar entropy and the heat of formation of GaN are given.