Microstructures,thermal diffusion and decomposition studies in the two phase solution grown mixed crystals of NaCl and KCl

Mixed NaCl-KCl crystals are grown from water solution. Thermal diffusion, decomposition and microstructures studies by employing the etching technique are reported. It is shown that microstructures consisting of alternate lamellae of NaCl and KCl arranged in 〈100〉 and 〈110〉 directions in the two-phase mixed NaCl-KCl crystals observed at room temperature get converted to the one consisting of random mixture of both the phases on finer scale on heating at 300°C for 30 hr. The dissociated matrix on heating at 600°C for 15 hr regains almost all the characteristics of a single crystal transforming the material into single-phase mixed (NaK) Cl crystals. The temperature dependence of the thermal diffusion is discussed.