INFLUENCE OFMg2+IONS DOPING ON THE STRUCTURE, MORPHOLOGY AND PHASE TRANSITION OFLiIO3CRYSTAL

Abstract

The influence of different concentrations of Mg2+ions doping on the structure, morphology and phase transition of LiIO3crystal was investigated. The best Mg2+-doped alpha-lithium iodate ( Mg :α- LiIO3) crystals for potential optical applications can be successfully grown by the aqueous solution method when the concentration of Mg2+ions in the initial mother solutions Cm< 0.001 M. Chemical component analysis shows the Mg :α- LiIO3crystal is a new system with the segregation coefficient k>1. The polarized Raman results are consistent with our conclusions that the Mg2+ion substitutes for the host Li+cation in the pure α- LiIO3crystals and results in the corresponding cation vacancies. As Cmincreases, inclusions, spontaneously crystalline grains, β phase of LiIO3and hillock-shape Mg :α- LiIO3crystals are induced respectively by different concentrations of Mg2+ions doping under the same crystal growth conditions. When Cm>0.1 M, the polarized Raman results indicate that larger amounts of Mg2+ions incorporated inhibit LiIO3growth and result in the hillock-shape morphology by destabilizing the crystal lattice and inducing lattice distortion.