Crystal structure of the Al 20 Mn 5.37 Ni 1.31 phase in the Al-Mn-Ni system.

The inter-metallic phase with composition Al 20 Mn 5.37 Ni 1.31 (icosa-aluminium penta-manganese nickel) was synthesized by high-temperature sinter-ing of a mixture with initial chemical composition Al 60 Mn 7 Ni 3 . Al 20 Mn 5.37 Ni 1.31 adopts the Co 2 Al 5 structure type in space-group type P 6 3 / mmc , replacing the Co atoms with the transition-metal atoms Mn and Ni. Structure analysis revealed that one of the two transition-metal sites is partially occupied by Ni [refined occupancy 0.342 (2)] and the other is co-occupied by Mn and Ni with a ratio of 0.895 (14):0.105 (14). The present refined chemical composition is supported by complementary energy-dispersive X-ray fluorescence (EDX) analysis and is in agreement with the previously determined Al-Mn-Ni phase diagram [Balanetskyy et al. (2011 ▸). J. Alloys Compd , 509 , 3795-3805].