The structure of the aluminium-abundant γ-brass-type Al8.6Mn4.4

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 18 h in space group R 3̄ 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 3̄ m (No. 166), rather than R 3 m (No. 160) as previously reported for the same intermetallic characterized by TEM measurements [Zeng et al. (2018). Acta Mater. 153 , 364–376].