Abstract

As many other compounds of the stochiometry M^IIMe^IVF₆ FeZrF₆ exhibits a transition from the cubic high-temperature to a hexagonal low-temperature phase. The former is of the ordered ReO₃-type [space group Fm3m] with Fe–F- and Zr–F-bond lengths of 205 and 199 pm respectively, while the latter crystallises in the LiSbF₆-structure [space group R[unk]m] with similar bond distances. The linear Fe–F–Zr-bridges of the cubic phase are bent below the phase transition. The geometrical data are in good agreement with spectroscopic and structural results, previously obtained on FeZrF₆ powder samples.