Crystal Structure of Li6BeF4ZrF8

Abstract

The crystal structure of Li₆BeF₄ZrF₈ has been determined by x‐ray diffraction. The tetragonal unit cell, having a=6.57, c=18.62 Å, contains four formula weights; the space group is D_4h¹⁹—I4₁amd. Discrete BeF₄^2— and ZrF₈^4— ions are connected by shared Li⁺ ions. The BeF₄^2— tetrahedron is quite regular with a Be–F distance of 1.57±0.01 Å; the ZrF₈^4— dodecahedron has two independent Zr–F bonds of 2.05±0.01 Å and 2.16±0.01 Å, and deviates considerably from the shape predicted by theory.