KABO晶体生长形态演化机理的分析

The analysis of morphology evolution of KABO crystal

用高温晶体生长实时观察装置,发现了KABO晶体生长形态随着生长体系过饱和度的增大从六方形态逐渐向三角形态过渡,然后又从三角形态逐渐向六方枝蔓晶形态过渡的过程.通过KABO生长溶液高温拉曼谱的测试结果,证明了溶液中存在[BO3]3-三角形、[AlO4]5-四面体生长基元.运用负离子配位多面体生长基元理论模型,分析了KABO晶体上述生长形态演化的机理.发现KABO的生长形态是由其内部结构和生长基元共同决定的,在不同过饱和度溶液中,KABO生长基元的种类和维度将会发生变化,由此相应引起了KABO的生长形态从六方形态到三角形态,又从三角形态向六方枝蔓晶形态的演变过程.

It was found via high temperature crystal growth in situ observation device that the morphology of KABO crystal varies with the degree of supersaturation of the crystal growth solution. The existence of [ BO3 ]^3- and [ AlO4 ]^5 - groWth units was proved by the results of high temperature Raman measurement of KABO crystal growth solution. The mechanism of KABO crystal morphology evolution was analyzed through the growth-units model of anionic coordination-polyhedra. It was found that the morphology of KABO crystal was determined simultaneously by its inner structure and the growth units. The kinds and dimensions of KABO growth units vary in solutions with different supersaturation, so accordingly, the morphology of KABO crystal changes from hexagonal to triangular morphology, and then from triangular to hexagonal dendritic morphology.