Diffuse scattering and thermal displacements of atoms

Sakuma, Takashi*; Basar, K.*; Xianglian*; Siagian, S.*; Takahashi, Haruyuki*; Igawa, Naoki   

Diffuse scatterings contain information about a short-range-order and thermal vibrations of atoms in crystals. We discuss the inter-atomic distance and temperature dependence of the correlation effects among thermal displacements of atoms. The intensity of neutron diffuse scattering for silver halides and copper halides was analyzed with the correlation effects among thermal displacements of first, second and third nearest beighboring atoms. the values of the correlation effects decrease rapidly with the increase of inter-atomic distance. Those also decrease with the decrease of temperature and the tendency of the temperature dependence agrees with that obtained by the simple Debye model of lattice vibrations.