Synthesis and Crystal Structure of the Low-Temperature Modification of Lithium Potassium Zinc Diphosphate LiKZnP2O7

摘要

A new polymorphic modification, α-LiKZnP2O7, has been synthesized, which is a low-temperature modification of the LiKZnP2O7 compound. The crystal structure is determined by the Rietveld method from the X-ray powder diffraction data. The compound crystallizes in the monoclinic system (space group Pc, a = 12.3621(3) A, b = 5.0655(1) A, c = 10.2365(3) A, β = 90.88(1)°, Z= 2) and has a framework structure similar to that of the high-temperature β phase. The framework is formed by the diphosphate groups and the oxygen tetra-hedra of the zinc and lithium atoms, which statistically uniformly occupy equivalent positions in the structure.