An aluminium-deficient Al8Cr5-type intermetallic with formula Al7.85Cr5.16 (octaaluminium pentachromium) was uncovered when high-pressure sintering of a mixture with composition Al11Cr4 was carried out. Structure analysis reveals that there are three co-occupied positions with refined occupancy factors for Al atoms being 0.958, 0.772 and 1/2. The present phase is confirmed to be isotypic with the previously reported rhombohedral Al8Cr5 ordered phase [Bradley & Lu (1937). Z. Kristallogr. 96, 20–37] and structurally closely related to the disordered phases of rhombohedral Al16Cr9.5 and cubic Al8Cr5.
