The Al 61.49 Mn 11.35 Ni 4 phase in the Al-Mn-Ni system.

An inter-metallic phase in the Al-Mn-Ni system crystallizing in space group Cmcm (No. 63) and refined formula Al 61.49 Mn 11.35 Ni 4 (called the R ' phase) has been synthesized by high-temperature sinter-ing of a mixture with initial chemical composition Al 60 Mn 7 Ni 3 . In comparison with the structure model of the previously reported R phase with composition Al 60 Mn 11 Ni 4 [Robinson (1954 ▸). Acta Cryst . 7 , 494-497], there are two mutually exchanged Mn and Ni sites together with one positionally disordered Al site [occupancy ratio 0.811 (8):0.121 (7)] and one partially occupied Mn site [s.o.f. 0.677 (5)] in the current structure model of the R ' phase.