Cr(Fe2Sb5)2 crystallizes in the monoclinic P2/m space group. Cr(1) is bonded to one Sb(1), one Sb(2), two equivalent Sb(6), and two equivalent Sb(7) atoms to form CrSb6 octahedra that share corners with four equivalent Fe(3)Sb6 octahedra, corners with four equivalent Fe(4)Sb6 octahedra, and edges with two equivalent Cr(1)Sb6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one Sb(3), one Sb(5), two equivalent Sb(10), and two equivalent Sb(8) atoms to form a mixture of edge and corner-sharing FeSb6 octahedra. The corner-sharing octahedral tilt angles range from 50-51°. In the second Fe site, Fe(2) is bonded to two equivalent Sb(4) and four equivalent Sb(9) atoms to form a mixture of edge and corner-sharing FeSb6 octahedra. The corner-sharing octahedral tilt angles are 50°. In the third Fe site, Fe(3) is bonded to one Sb(6), one Sb(8), two equivalent Sb(1), and two equivalent Sb(3) atoms to form FeSb6 octahedra that share corners with four equivalent Cr(1)Sb6 octahedra, corners with four equivalent Fe(1)Sb6 octahedra, and edges with two equivalent Fe(3)Sb6 octahedra. The corner-sharing octahedral tilt angles range from 50-51°. In the fourth Fe site, Fe(4) is bonded to two equivalent Sb(7) and four equivalent Sb(2) atoms to form FeSb6 octahedra that share corners with eight equivalent Cr(1)Sb6 octahedra and edges with two equivalent Fe(4)Sb6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. In the fifth Fe site, Fe(5) is bonded to one Sb(10), one Sb(9), two equivalent Sb(4), and two equivalent Sb(5) atoms to form a mixture of edge and corner-sharing FeSb6 octahedra. The corner-sharing octahedral tilt angles range from 50-51°. There are ten inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a 3-coordinate geometry to one Cr(1) and two equivalent Fe(3) atoms. In the second Sb site, Sb(2) is bonded in a 3-coordinate geometry to one Cr(1) and two equivalent Fe(4) atoms. In the third Sb site, Sb(3) is bonded in a 3-coordinate geometry to one Fe(1) and two equivalent Fe(3) atoms. In the fourth Sb site, Sb(4) is bonded in a 3-coordinate geometry to one Fe(2) and two equivalent Fe(5) atoms. In the fifth Sb site, Sb(5) is bonded in a 3-coordinate geometry to one Fe(1) and two equivalent Fe(5) atoms. In the sixth Sb site, Sb(6) is bonded in a 3-coordinate geometry to two equivalent Cr(1) and one Fe(3) atom. In the seventh Sb site, Sb(7) is bonded in a 3-coordinate geometry to two equivalent Cr(1) and one Fe(4) atom. In the eighth Sb site, Sb(8) is bonded in a 3-coordinate geometry to one Fe(3) and two equivalent Fe(1) atoms. In the ninth Sb site, Sb(9) is bonded in a 3-coordinate geometry to one Fe(5) and two equivalent Fe(2) atoms. In the tenth Sb site, Sb(10) is bonded in a 3-coordinate geometry to one Fe(5) and two equivalent Fe(1) atoms.
Cr(Fe2Sb5)2 crystallizes in the monoclinic P2/m space group. Cr(1) is bonded to one Sb(1), one Sb(2), two equivalent Sb(6), and two equivalent Sb(7) atoms to form CrSb6 octahedra that share corners with four equivalent Fe(3)Sb6 octahedra, corners with four equivalent Fe(4)Sb6 octahedra, and edges with two equivalent Cr(1)Sb6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. The Cr(1)-Sb(1) bond length is 2.68 Å. The Cr(1)-Sb(2) bond length is 2.67 Å. Both Cr(1)-Sb(6) bond lengths are 2.68 Å. Both Cr(1)-Sb(7) bond lengths are 2.68 Å. There are five inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one Sb(3), one Sb(5), two equivalent Sb(10), and two equivalent Sb(8) atoms to form a mixture of edge and corner-sharing FeSb6 octahedra. The corner-sharing octahedral tilt angles range from 50-51°. The Fe(1)-Sb(3) bond length is 2.58 Å. The Fe(1)-Sb(5) bond length is 2.60 Å. Both Fe(1)-Sb(10) bond lengths are 2.61 Å. Both Fe(1)-Sb(8) bond lengths are 2.60 Å. In the second Fe site, Fe(2) is bonded to two equivalent Sb(4) and four equivalent Sb(9) atoms to form a mixture of edge and corner-sharing FeSb6 octahedra. The corner-sharing octahedral tilt angles are 50°. Both Fe(2)-Sb(4) bond lengths are 2.59 Å. All Fe(2)-Sb(9) bond lengths are 2.61 Å. In the third Fe site, Fe(3) is bonded to one Sb(6), one Sb(8), two equivalent Sb(1), and two equivalent Sb(3) atoms to form FeSb6 octahedra that share corners with four equivalent Cr(1)Sb6 octahedra, corners with four equivalent Fe(1)Sb6 octahedra, and edges with two equivalent Fe(3)Sb6 octahedra. The corner-sharing octahedral tilt angles range from 50-51°. The Fe(3)-Sb(6) bond length is 2.55 Å. The Fe(3)-Sb(8) bond length is 2.57 Å. Both Fe(3)-Sb(1) bond lengths are 2.57 Å. Both Fe(3)-Sb(3) bond lengths are 2.60 Å. In the fourth Fe site, Fe(4) is bonded to two equivalent Sb(7) and four equivalent Sb(2) atoms to form FeSb6 octahedra that share corners with eight equivalent Cr(1)Sb6 octahedra and edges with two equivalent Fe(4)Sb6 octahedra. The corner-sharing octahedral tilt angles range from 50-52°. Both Fe(4)-Sb(7) bond lengths are 2.52 Å. All Fe(4)-Sb(2) bond lengths are 2.57 Å. In the fifth Fe site, Fe(5) is bonded to one Sb(10), one Sb(9), two equivalent Sb(4), and two equivalent Sb(5) atoms to form a mixture of edge and corner-sharing FeSb6 octahedra. The corner-sharing octahedral tilt angles range from 50-51°. The Fe(5)-Sb(10) bond length is 2.59 Å. The Fe(5)-Sb(9) bond length is 2.59 Å. Both Fe(5)-Sb(4) bond lengths are 2.61 Å. Both Fe(5)-Sb(5) bond lengths are 2.60 Å. There are ten inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a 3-coordinate geometry to one Cr(1) and two equivalent Fe(3) atoms. In the second Sb site, Sb(2) is bonded in a 3-coordinate geometry to one Cr(1) and two equivalent Fe(4) atoms. In the third Sb site, Sb(3) is bonded in a 3-coordinate geometry to one Fe(1) and two equivalent Fe(3) atoms. In the fourth Sb site, Sb(4) is bonded in a 3-coordinate geometry to one Fe(2) and two equivalent Fe(5) atoms. In the fifth Sb site, Sb(5) is bonded in a 3-coordinate geometry to one Fe(1) and two equivalent Fe(5) atoms. In the sixth Sb site, Sb(6) is bonded in a 3-coordinate geometry to two equivalent Cr(1) and one Fe(3) atom. In the seventh Sb site, Sb(7) is bonded in a 3-coordinate geometry to two equivalent Cr(1) and one Fe(4) atom. In the eighth Sb site, Sb(8) is bonded in a 3-coordinate geometry to one Fe(3) and two equivalent Fe(1) atoms. In the ninth Sb site, Sb(9) is bonded in a 3-coordinate geometry to one Fe(5) and two equivalent Fe(2) atoms. In the tenth Sb site, Sb(10) is bonded in a 3-coordinate geometry to one Fe(5) and two equivalent Fe(1) atoms.