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PrIr2 is Cubic Laves structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to twelve equivalent Ir atoms. All Pr–Ir bond lengths are 3.20 Å. Ir is bonded to six equivalent Pr and six equivalent Ir atoms to form a mixture of face, edge, and corner-sharing IrPr6Ir6 cuboctahedra. All Ir–Ir bond lengths are 2.73 Å.
Pr3Ir is Cementite structured and crystallizes in the orthorhombic Pnma space group. The structure is two-dimensional and consists of two Pr3Ir sheets oriented in the (0, 0, 1) direction. there are two inequivalent Pr sites. In the first Pr site, Pr is bonded in a 2-coordinate geometry to two equivalent Ir atoms. There are one shorter (2.93 Å) and one longer (2.97 Å) Pr–Ir bond lengths. In the second Pr site, Pr is bonded in a distorted bent 150 degrees geometry to two equivalent Ir atoms. There are one shorter (2.92 Å) and one longer (3.01 Å) Pr–Ir bond lengths. Ir is bonded in a 6-coordinate geometry to six Pr atoms.
Pr7Ir3 crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. there are three inequivalent Pr sites. In the first Pr site, Pr is bonded in a distorted trigonal non-coplanar geometry to three equivalent Ir atoms. All Pr–Ir bond lengths are 2.91 Å. In the second Pr site, Pr is bonded in a distorted water-like geometry to two equivalent Ir atoms. Both Pr–Ir bond lengths are 2.94 Å. In the third Pr site, Pr is bonded in a 3-coordinate geometry to three equivalent Ir atoms. There are one shorter (2.97 Å) and two longer (2.99 Å) Pr–Ir bond lengths. Ir is bonded in a 6-coordinate geometry to six Pr atoms.