On the space group of MgAl₂O₄spinel

Abstract

Abstract [001] electron diffraction patterns of MgAl2O4 spinel show (hk0) reflections with h + k = 4n + 2 ((200), (420), etc.) that violate the accepted Fd3m space group of this material. Since these ‘forbidden’ reflections cannot be attributed to double diffraction, non-zero Laue zones, or a second phase, this result is consistent with Grimes' recent suggestion that the correct space group for MgAl2O4 spinel is F43m.