The structure of the aluminium-abundant γ-brass-type Al(8.6)Mn(4.4)

An aluminium-abundant Al(8)Mn(5)/γ-brass-type inter­metallic with formula Al(8.6)Mn(4.4), which is isotypic with γ-Al(8)Cr(5) and γ-Al(8)V(5), was discovered by high-temperature sinter­ing of an Al/Mn mixture with initial composition Al(2)Mn. Structure analysis revealed that one special position (Wyckoff site 18h in space group R [Image: see text] m) is shared by Al and Mn, with refined site occupancy factors of 0.7 and 0.3, respectively. The present low-temperature Al(8)Mn(5)-type phase crystallizes in the centrosymmetric space group R [Image: see text] m (No. 166), rather than R3m (No. 160) as previously reported for the same inter­metallic characterized by TEM measurements [Zeng et al. (2018 ▸). Acta Mater. 153, 364–376]. [Image: see text]