The Debye-Waller factor for the noble gas solids

Abstract

The mean-square nuclear displacements 〈u2〉, the Debye Θ's associated with the 〈u2〉, and the Debye Θ′'s associated with the temperature derivatives of 〈u2〉 at constant volume have been calculated for the noble gas solids Ne, Ar, Kr, and Xe as a function of temperature and volume using self-consistent phonon theory. Instead of using the equation of state which gives volumes which are consistently smaller than the experimental volumes, the experimental lattice parameters at the saturated vapor pressure were used. In the case of neon, the theoretical 〈u2〉 were also obtained as a function of temperature and the experimental lattice volume atT=0K. The interaction forces are described by a nearest neighbor (12–6) Mie–Lennard-Jones potential.