The Spinels CuCr₂O₄ and CuRh₂O₄

Rietveld refinement of X-ray powder data measured for CuCr₂O₄ [copper(II) dichromium(III) tetraoxide] and CuRh₂O₄ [copper(II) dirhodium(III) tetraoxide] indicates that their structures at room temperature are centrosymmetric, I4₁/amd, rather than as previously reported, noncentrosymmetric I-42 d. Trial refinement in I-42 d shows insignificant improvement in the agreement between observed and calculated intensities, and no statistically significant deviation from a centrosymmetric structure.

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