Fe9Ir3B4 crystallizes in the monoclinic Pm space group. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 2-coordinate geometry to one B(1), one B(2), and one B(4) atom. In the second Fe site, Fe(2) is bonded in a 2-coordinate geometry to one B(1), one B(2), and one B(3) atom. In the third Fe site, Fe(3) is bonded in a 2-coordinate geometry to one B(2), one B(3), and one B(4) atom. In the fourth Fe site, Fe(4) is bonded in a 2-coordinate geometry to one B(1), one B(3), and one B(4) atom. In the fifth Fe site, Fe(5) is bonded in a 2-coordinate geometry to one B(1) and two equivalent B(2) atoms. There are three inequivalent Ir sites. In the first Ir site, Ir(1) is bonded in a 2-coordinate geometry to one B(2) and two equivalent B(1) atoms. In the second Ir site, Ir(2) is bonded in a 2-coordinate geometry to one B(3) and two equivalent B(4) atoms. In the third Ir site, Ir(3) is bonded in a 2-coordinate geometry to one B(4) and two equivalent B(3) atoms. There are four inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to one Fe(5), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(4), and two equivalent Ir(1) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(5), and one Ir(1) atom. In the third B site, B(3) is bonded in a 9-coordinate geometry to two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), one Ir(2), and two equivalent Ir(3) atoms. In the fourth B site, B(4) is bonded in a 9-coordinate geometry to two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(4), one Ir(3), and two equivalent Ir(2) atoms.
Fe9Ir3B4 crystallizes in the monoclinic Pm space group. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 2-coordinate geometry to one B(1), one B(2), and one B(4) atom. The Fe(1)-B(1) bond length is 2.09 Å. The Fe(1)-B(2) bond length is 2.07 Å. The Fe(1)-B(4) bond length is 2.44 Å. In the second Fe site, Fe(2) is bonded in a 2-coordinate geometry to one B(1), one B(2), and one B(3) atom. The Fe(2)-B(1) bond length is 2.11 Å. The Fe(2)-B(2) bond length is 2.12 Å. The Fe(2)-B(3) bond length is 2.42 Å. In the third Fe site, Fe(3) is bonded in a 2-coordinate geometry to one B(2), one B(3), and one B(4) atom. The Fe(3)-B(2) bond length is 2.36 Å. The Fe(3)-B(3) bond length is 2.14 Å. The Fe(3)-B(4) bond length is 2.11 Å. In the fourth Fe site, Fe(4) is bonded in a 2-coordinate geometry to one B(1), one B(3), and one B(4) atom. The Fe(4)-B(1) bond length is 2.37 Å. The Fe(4)-B(3) bond length is 2.11 Å. The Fe(4)-B(4) bond length is 2.12 Å. In the fifth Fe site, Fe(5) is bonded in a 2-coordinate geometry to one B(1) and two equivalent B(2) atoms. The Fe(5)-B(1) bond length is 2.14 Å. There is one shorter (2.16 Å) and one longer (2.58 Å) Fe(5)-B(2) bond length. There are three inequivalent Ir sites. In the first Ir site, Ir(1) is bonded in a 2-coordinate geometry to one B(2) and two equivalent B(1) atoms. The Ir(1)-B(2) bond length is 2.14 Å. There is one shorter (2.16 Å) and one longer (2.59 Å) Ir(1)-B(1) bond length. In the second Ir site, Ir(2) is bonded in a 2-coordinate geometry to one B(3) and two equivalent B(4) atoms. The Ir(2)-B(3) bond length is 2.17 Å. There is one shorter (2.19 Å) and one longer (2.55 Å) Ir(2)-B(4) bond length. In the third Ir site, Ir(3) is bonded in a 2-coordinate geometry to one B(4) and two equivalent B(3) atoms. The Ir(3)-B(4) bond length is 2.14 Å. There is one shorter (2.18 Å) and one longer (2.57 Å) Ir(3)-B(3) bond length. There are four inequivalent B sites. In the first B site, B(1) is bonded in a 9-coordinate geometry to one Fe(5), two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(4), and two equivalent Ir(1) atoms. In the second B site, B(2) is bonded in a 9-coordinate geometry to two equivalent Fe(1), two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(5), and one Ir(1) atom. In the third B site, B(3) is bonded in a 9-coordinate geometry to two equivalent Fe(2), two equivalent Fe(3), two equivalent Fe(4), one Ir(2), and two equivalent Ir(3) atoms. In the fourth B site, B(4) is bonded in a 9-coordinate geometry to two equivalent Fe(1), two equivalent Fe(3), two equivalent Fe(4), one Ir(3), and two equivalent Ir(2) atoms.