Some Thermomechanical Properties of an FCC Helium Cryocrystal

The paper presents analytic expressions of the Helmholtz free energy, the crystal parameters, the nearest neighbor distance between two atoms, the isothermal compressibility, the thermal expansion coefficient, the heat capacity at constant volume, the Gruneisen parameter, the isothermal elastic modulus, the Young modulus, the mean squared displacement and the Debye–Waller factor for FCC monoatomic crystal builded by the statistical moment method. The paper performs numerical calculation of the obtained theoretical results for FCC quantum crystals ³He and ⁴He using the Lennard–Jones (6–12) pair interaction potential and the coordination sphere method. Some calculated results are compared with the experimental data and other calculations.