Cu2Sb-type (anti-type) Mn2Sb. P4/nmm #129, Z=2, 6 atoms. a=4.074 Å, c=6.570 Å, c/a=1.613. ICSD 103470. Ferrimagnetic, Tc≈550K. Mn(I) at 2a, Mn(II) at 2c (z≈0.280), Sb at 2b.