X-ray diffraction on (KBr)1−x(KCN)xmixed crystals

Abstract

X-ray powder diffraction experiments have been carried out on eight mixed crystals (x=0.20, 0.50, 0.53, 0.65, 0.70, 0.80, 0.85, and 0.90) in the temperature range from 15–300 K. The phase diagram shows cubic, rhombohedral, monoclinic, and triclinic phases, and a glass state. The structural order parameters and the width of the cubic powder lines have been studied in detail as a function of temperature. The character of the transition from the cubic to the low-temperature phases changes from strongly discontinuous for x=0.9 to quasicontinuous for x=0.65. The glass state can be described by distributions of shear strains.