Li_(1+2x)Ti_(2-x)Mg_xP_3O_(12)固溶体系统结构^(31)P NMR研究

^(31)P NMR STUDIES ON THE STRUCTURE OF Li_(1+2x)Ti_(2-x)Mg_xP_3O_(12) SYSTEMS

本文应用固体高分辨^(31)P NMR技术,以P原子作为结构探针,对以LiTi_2P_3O_(12)为基质的Mg掺杂固溶体系统快离子导体的结构进行了研究。并利用P原子第二配位层阳离子场强与其化学位移的关系,确定了不同化学位移^(31)P NMR谱线与固溶体结构中P原子局部结构单元Q°之间的关系,解释了Mg的掺入所引起的晶体结构的变化。

The structure of solid solutions Li1+2xTi2-xMgxP3O12, in which magnesium were doped, were studied by solid-state high-resolution 31P MAS NMR with P atom as a probe of the structure. The relationship between 31P NMR lines with different chemical shifts and the local structure units Q°in solid solution systems were determined by using a linear correlation between 31P isotropic chemical shift and field strength F of the cation of the second coordination sphere. These results give interpretation for the change of local structure due to the substitution of titanium by magnesium.