Uranium Mononitride: Heat Capacity and Thermodynamic Properties from 5° to 350°K

The low-temperature heat capacity of UN was determined by adiabatic calorimetry and found to have a normal sigmate temperature dependence, except for the presence of an anomaly near 52°K associated with antiferromagnetic ordering of the electron spins. At 298.15°K the heat capacity (CP), entropy (S°), enthalpy function [(H°—H°0)/T], and Gibbs energy function [—(G°—H°0)/T] are, respectively, 11.43, 14.97, 7.309, and 7.664 cal/(gfm·°K).