Mg13Ir3 crystallizes in the trigonal R-3c space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a linear geometry to two equivalent Ir(1) atoms. In the second Mg site, Mg(2) is bonded in a bent 150 degrees geometry to two equivalent Ir(1) atoms. In the third Mg site, Mg(3) is bonded in a trigonal planar geometry to three equivalent Ir(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 2-coordinate geometry to two equivalent Ir(1) atoms. Ir(1) is bonded in a 9-coordinate geometry to one Mg(3), two equivalent Mg(1), two equivalent Mg(2), and four equivalent Mg(4) atoms.
Mg13Ir3 crystallizes in the trigonal R-3c space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a linear geometry to two equivalent Ir(1) atoms. Both Mg(1)-Ir(1) bond lengths are 2.71 Å. In the second Mg site, Mg(2) is bonded in a bent 150 degrees geometry to two equivalent Ir(1) atoms. Both Mg(2)-Ir(1) bond lengths are 2.73 Å. In the third Mg site, Mg(3) is bonded in a trigonal planar geometry to three equivalent Ir(1) atoms. All Mg(3)-Ir(1) bond lengths are 2.75 Å. In the fourth Mg site, Mg(4) is bonded in a 2-coordinate geometry to two equivalent Ir(1) atoms. There is one shorter (2.69 Å) and one longer (2.80 Å) Mg(4)-Ir(1) bond length. Ir(1) is bonded in a 9-coordinate geometry to one Mg(3), two equivalent Mg(1), two equivalent Mg(2), and four equivalent Mg(4) atoms.