Self-consistent calculations of the dynamic and thermodynamic properties of solid helium

摘要

The results of studies of physical properties of quantum crystals i.e. b.c.c. ~3He and h.c.p. ~4He in the reduced, all neighbors approximation of the self-consistent phonon theory (SCPT) are presented. The system of equations describing the temperature and pressure variations of the dynamic and thermodynamic quantities for these crystals has been solved for the best grounded theoretically, in the case of solid helium, the renormalized potential: the generalized version of the (exp,m) Buckingham, the (n,m) Lennard-Jones and the (exp,exp) Morse. Optimal values of the potential constants have been calculated with the help of self-consistently method using experimental data for the zero-point properties: the internal energy, volume, compressibility and the Debye'a characteristic temperature determined at low temperature. The obtained potential functions parameters were in turn used to calculate the dynamic and thermodynamic properties of solid helium.