IrP3O9 crystallizes in the triclinic P-1 space group. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to two equivalent O(1), two equivalent O(7), and two equivalent O(8) atoms to form IrO6 octahedra that share corners with two equivalent P(3)O4 tetrahedra and corners with four equivalent P(2)O4 tetrahedra. In the second Ir site, Ir(2) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(9) atoms to form IrO6 octahedra that share corners with two equivalent P(3)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(5), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Ir(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-52°. In the second P site, P(2) is bonded to one O(1), one O(2), one O(6), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Ir(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-57°. In the third P site, P(3) is bonded to one O(3), one O(4), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Ir(1)O6 octahedra,  a cornercorner with one Ir(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-57°. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ir(1) and one P(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one P(1) and one P(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ir(2) and one P(3) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Ir(2) and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one P(2) and one P(3) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Ir(1) and one P(3) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one Ir(1) and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Ir(2) and one P(1) atom.
IrP3O9 crystallizes in the triclinic P-1 space group. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to two equivalent O(1), two equivalent O(7), and two equivalent O(8) atoms to form IrO6 octahedra that share corners with two equivalent P(3)O4 tetrahedra and corners with four equivalent P(2)O4 tetrahedra. Both Ir(1)-O(1) bond lengths are 2.05 Å. Both Ir(1)-O(7) bond lengths are 2.06 Å. Both Ir(1)-O(8) bond lengths are 2.05 Å. In the second Ir site, Ir(2) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(9) atoms to form IrO6 octahedra that share corners with two equivalent P(3)O4 tetrahedra and corners with four equivalent P(1)O4 tetrahedra. Both Ir(2)-O(4) bond lengths are 2.04 Å. Both Ir(2)-O(5) bond lengths are 2.05 Å. Both Ir(2)-O(9) bond lengths are 2.05 Å. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(5), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Ir(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-52°. The P(1)-O(2) bond length is 1.58 Å. The P(1)-O(3) bond length is 1.60 Å. The P(1)-O(5) bond length is 1.49 Å. The P(1)-O(9) bond length is 1.49 Å. In the second P site, P(2) is bonded to one O(1), one O(2), one O(6), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Ir(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one P(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-57°. The P(2)-O(1) bond length is 1.49 Å. The P(2)-O(2) bond length is 1.59 Å. The P(2)-O(6) bond length is 1.58 Å. The P(2)-O(8) bond length is 1.49 Å. In the third P site, P(3) is bonded to one O(3), one O(4), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Ir(1)O6 octahedra,  a cornercorner with one Ir(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 50-57°. The P(3)-O(3) bond length is 1.58 Å. The P(3)-O(4) bond length is 1.49 Å. The P(3)-O(6) bond length is 1.59 Å. The P(3)-O(7) bond length is 1.49 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ir(1) and one P(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one P(1) and one P(2) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one P(1) and one P(3) atom. In the fourth O site, O(4) is bonded in a distorted bent 120 degrees geometry to one Ir(2) and one P(3) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Ir(2) and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one P(2) and one P(3) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Ir(1) and one P(3) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one Ir(1) and one P(2) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Ir(2) and one P(1) atom.