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

Abstract

Single crystals of cobalt digallium tetraoxide, CoGa 2 O 4 , have been grown by cooling slowly a 1:1 mixture of CoO and Ga 2 O 3 from 1473 K to room temperature under the presence of a PbF 2 flux. The compound crystallizes with the cubic spinel structure (space group Fd \overline{3} m ). The occupancy refinement based on single-crystal X-ray diffraction data shows CoGa 2 O 4 to be a largely normal spinel with an inversion parameter of 0.575 (4), resulting in a structural formula of IV (Co 0.425 Ga 0.575 ) VI [Co 0.575 Ga 1.425 ]O 4 , where IV () and VI [] represent the tetrahedral and the octahedral sites, respectively.