Effect of temperature on nucleation and growth of cadmium oxalate single crystals in silica gels

Abstract

In continuation of our earlier work on the gel growth of single crystals, this paper presents results on the effect of temperature on nucleation and growth of cadmium oxalate single crystals. It has been found that the nucleation centres decrease drastically (to as low as two) as the temperature increases. Low nucleation centres resulted in larger and more perfect single crystals. The decrease in nucleation centres at higher temperature has been interpreted in terms of a decrease in supersaturation, an increase in critical size of nucleus and free energy of nucleus formation. The growth rates of the crystals measured as a function of temperature has clearly indicated that the crystal growth process in gel is a one-dimensional diffusion controlled process.