Ir2Si crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to six equivalent Ir(2) and five equivalent Si(1) atoms to form a mixture of distorted corner and face-sharing IrSi5Ir6 trigonal bipyramids. In the second Ir site, Ir(2) is bonded in a 14-coordinate geometry to two equivalent Ir(2), six equivalent Ir(1), and six equivalent Si(1) atoms. Si(1) is bonded in a 11-coordinate geometry to five equivalent Ir(1) and six equivalent Ir(2) atoms.
Ir2Si crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to six equivalent Ir(2) and five equivalent Si(1) atoms to form a mixture of distorted corner and face-sharing IrSi5Ir6 trigonal bipyramids. All Ir(1)-Ir(2) bond lengths are 2.79 Å. There are three shorter (2.42 Å) and two longer (2.75 Å) Ir(1)-Si(1) bond lengths. In the second Ir site, Ir(2) is bonded in a 14-coordinate geometry to two equivalent Ir(2), six equivalent Ir(1), and six equivalent Si(1) atoms. Both Ir(2)-Ir(2) bond lengths are 2.75 Å. All Ir(2)-Si(1) bond lengths are 2.79 Å. Si(1) is bonded in a 11-coordinate geometry to five equivalent Ir(1) and six equivalent Ir(2) atoms.