Thermophysical properties of the intermetallic Mn3MN perovskites I. Heat capacity of the manganese nitride Mn4N

The heat capacity of Mn4N has been determined in the range from 5 to 345 K by adiabatic calorimetry and between 335 and 500 K by d.s.c. No anomaly was found in the temperature range covered. The thermodynamic functions at 298.15 K are CpR = 15.01, So(T)R = 17.19, {Ho(T)−Ho(0)}R = 2712.8 K, and {Go(T)−Ho(0)}RT = − 8.089. From the analysis of the various contributions to the heat capacity the values γ = 0.042 J · mol−1 · K−2, for the electronic coefficient, and ΘrmD(0) = 433 K, for the Debye temperature at T → 0, have been obtained. The determination of the lattice contribution for T < 350 K will allow us to use it as a common lattice base line to estimate the lattice contribution to Cp of other members of the series.