Choice of Fluxes for the Crystal Growth of Oxides from High-temperature Solutions

Abstract

In the growth of single crystals from high-temperature solutions, the flux has been normally chosen by trial and error procedures, taking into account of previous experiences. In this study, a guide to the choice of suitable fluxes for the crystal growth of oxides from high-temperature solutions was proposed. In this guide, the criteria were made up by use of some fundamental informations, e. g. ionic radius, melting point, ionicity of chemical bondings, Dietzel's parameter and acidity and basicity. The results on growth ofα-Al₂O₃ single crystals were shown and discussed. A method for growing CaWO₄ single crystals was proposed and the experiment was carried out by using Na₂WO₄ as the flux, which showed that the colorless and transparent CaWO4 single crystals were grown by slowly cooling the high-temperature solution. Also, the growth of NaNd(MoO₄)₂ single crystals was discussed.