Mechanical and thermal properties of NpO2 using LSDA+U approach

The elastic constants, bulk modulus, shear modulus, Young׳s modulus, Debye temperature, isobaric heat capacity and minimum thermal conductivity are estimated for NpO2 using plane-wave pseudopotential method within the local spin density approximation plus Hubbard U (LSDA+U) theory. The computed lattice constants are in good agreement with the available experimental results and then three independent elastic constants were computed by means of the stress–strain method. From the knowledge of the elastic constants, the values of Young׳s modulus, Poisson, Debye temperature and minimum thermal conductivity are obtained and they are 218 GPa, 0.288, 453.5 K and 0.99 Wm−1 K−1, respectively. The obtained mechanical and thermal properties of NpO2 are in agreement with the previous experimental and theoretical data. Our investigations which are unobtainable from previous report can provide valuable reference in the future.