DIFFUSE-SCATTERING OF ALPHA-AGI

The theoretical treatment of the diffuse scattering including the correlations among the thermal displacements of atoms were described. It was applied to the analysis of the observed intensities of the diffuse scattering of alpha-AgI. The same thermal parameters which were obtained from the analysis of Debye lines based on the distribution of Ag atoms over 48 (j) sites with a harmonic thermal vibration were used in the calculation. The first peak in the diffuse background of alpha-AgI consisted of the static diffuse scattering among silver atoms and the thermal scattering. Most of the intensities of the diffuse scattering in the range of sin theta/lambda greater than that of the first peak corresponded to the thermal scattering. Main contribution to the intensity of the second peak was from the correlation among the thermal displacements of nearest neighbor silver and iodine atoms.