MEANS SQUARE DISPLACEMENTS OF A SUBSTITUTIONAL DEFECT AND ITS NEAREST NEIGHBOURS IN KI

Abstract
The means square displacements of both the cation and anion substitutional defects and those of their nearest neighbours in KI are calculated in the frame work of a scattering matrix formalism. Our results show that the means square amplitudes of the defect atom such as the Rb⁺ in KI is much larger than the value of Rb⁺ in RbI as also of K⁺ in KI. The means square displacements of the nearest neighbours in the defect environment are not that significanltly altered from their values in the host crystal environment. The other salient features observed from our calculations are also discussed.