Temperature dependence of thermal vibrations in lead as determined from short-wavelength neutron diffraction data

The temperature dependence of the atomic thermal motion in lead has been studied by analysis of diffraction measurements with 0.535 and 0.844 Å neutrons. Full single-crystal data sets were collected at ten temperatures ranging from 100 K to the vicinity of the melting point at 600 K. The data were interpreted in the anharmonic one-particle-potential formalism. Significant values for both isotropic and anisotropic quartic-anharmonic potential parameters were obtained, but a single temperature-independent one- particle potential was found sufficient to describe the temperature dependence of the atomic temperature factor only above ~4θ_M, where θ_M is the Debye temperature.