On the space group of MgAl2O4spinel

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.