Abstract
The title single-crystal was obtained during the synthesis of a Mg-Al-Zn-Ga alloy, which was achieved by subjecting the alloy to elevated pressures and temperatures. The compound crystallizes in the space group Im3 (No. 204), with seven distinct metal-atom sites. One of these is occupied by gallium, two by aluminium and zinc, one by zinc and magnesium, and three by magnesium. The structure model contains a vacancy-centred Bergman cluster and a 26-face polyhedron centred on one of the magnesium sites. The crystal structure framework in this study shows a marked similarity to previously examined frameworks, but also evinces significant differences [Edagawa et al. (1992). Philos. Mag. B 65, 1011-1023].