Nucleation and growth of KClO₄ single crystals in silica gels

Abstract

As part of a continuing effort on the growth of KClO₄ single crystals in gels, this paper describes the variation of nucleation density and growth of these crystals as a function of concentration of feed solution, gel ageing, gel density, gel pH and intermediate neutral gel column. While high density and high pH gels have been found to produce opaque crystals, good quality transparent single crystals have been obtained at low density and low pH gels. It is observed that the intermediate neutral gel column and gel ageing considerably reduce the number of nucleation sites. A simple procedure to control nucleation sites in gels has been adopted, which has resulted in a dramatic increase in the size of the crystals.