LiAl5O8高压相变研究

 运用金刚石压砧同步辐射X射线衍射，对尖晶石结构的LiAl₅O₈进行了高压原位研究。实验发现：在高压下，一组LiAl₅O₈的新相衍射峰出现，随着压力的增加，其新相衍射峰逐渐增强，当压力增加到45.0 GPa时，LiAl₅O₈的低压相衍射峰全部消失，而形成了一组高压新相衍射峰。采用指标化程序对衍射数据进行处理和分析，确定这一高压新相为正交晶系结构，其晶胞参数为a=0.995 9 nm，b=0.644 7 nm，c=0.333 4 nm ，空间群为Pmm2。

Pressure-Iduced Phase Transition of LiAl5O8

A phase transition concerning lithium aluminate oxide(LiAl5O8) was observed.High pressure synchrotron radiation X-ray diffraction was used to explore its structure in a diamond anvil cell up to 47.0 GPa.We found the two phases are coexisted over a very large pressure range in the experiments.According to the analysis on the dynamic change of diffraction peaks with the increasing of pressure and the data reduction using indexed program,a new high-pressure phase of LiAl5O8 was identified at pressure below 45.0 GPa.This new phase has potentially a orthorhombic structure with a=0.995 9 nm,b=0.644 7 nm,c=0.333 4 nm and the space group of Pmm2.