STRUCTURAL TRANSITIONS DURING THERMAL DESTRUCTION IN THE FAMILY OF ZINC FLUORIDOZIRCONATE CRYSTAL HYDRATES

The structure of ZnZrF · 6HO and ZnZrF · 5HO (high- and low-temperature forms) crystal hydrates and their products of thermal destruction: ZnZrF · 4HO, ZnZrF · 2HO, ZnZrF and ZnZrF · 2HO have been studied. With the exception of ZnZrF · 2HO, the compounds of ZnZrF · nHO (n = 6, 5, 4, 2, 0) are isostructural to their formula analogues: NiZrF · 6HO, α- and β-MgZrF · 5HO, CuZrF · 4HO, MgZrF · 2HO, MgZrF, respectively. The structure of ZnZrF · 2HO is built from unique infinite network anionic layers , in which ZrF square antiprisms are formed tetranuclear cycles and are shared six of their vertices with four neighboring Zr-polyhedra according to the law "...edge-edge–vertex–vertex—..."; ZnF(HO)-octahedra link Zr-layers to each other into a framework.