X-ray Studies on Precipitation of Metastable Centers in Mixed Crystals NaCl-CdCl₂

Abstract

Mixed crystals NaCl-CdCl 2 containing a few mole per cent of CdCl 2 were examined by X-ray method. By a certain heat treatment, precipitates of a structure having f.c.c. lattice with lattice constant twice as that of the matrix are formed within the matrix. By another heat treatment, there appear diffuse spots corresponding to the intensity distribution of rods extended to the directions of <100> at odd-order reciprocal-lattice points of the above mentioned structure. Crystal structure of the precipitates, which is identified to be CdCl 2 ·6NaCl, are determined, and at the same time, main features of the diffuse reflexions are explained on the basis of the structure.