Inversion parameter of the CoGa2O4 spinel determined from single-crystal X-ray data

Single crystals of cobalt digallium tetraoxide, CoGa2O4, have been grown by cooling slowly a 1:1 mixture of CoO and Ga2O3 from 1473 K to room temperature under the presence of a PbF2 flux. The compound crystallizes with the cubic spinel structure (space group Fd (3) over barm). The occupancy refinement based on single-crystal X-ray diffraction data shows CoGa2O4 to be a largely normal spinel with an inversion parameter of 0.575 (4), resulting in a structural formula of (IV)(Co0.425Ga0.575) (VI)[Co0.575Ga1.425]O-4, where (IV)() and (VI)[] represent the tetrahedral and the octahedral sites, respectively.