CrFeNb crystallizes in the orthorhombic Amm2 space group. There are six inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1); three Nb(2,2); three equivalent Cr(1); four equivalent Cr(2); one Fe(3); two equivalent Fe(1); and two equivalent Fe(2) atoms. In the second Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(2); three Nb(1,1); two equivalent Cr(2); three equivalent Cr(1); one Fe(1); two equivalent Fe(3); and four equivalent Fe(2) atoms. In the third Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(2); three Nb(1,1); two equivalent Cr(2); three equivalent Cr(1); one Fe(1); two equivalent Fe(3); and four equivalent Fe(2) atoms. In the fourth Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1); three Nb(2,2); three equivalent Cr(1); four equivalent Cr(2); one Fe(3); two equivalent Fe(1); and two equivalent Fe(2) atoms. In the fifth Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(2); three Nb(1,1); two equivalent Cr(2); three equivalent Cr(1); one Fe(1); two equivalent Fe(3); and four equivalent Fe(2) atoms. In the sixth Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Nb(2), three equivalent Cr(1), four equivalent Cr(2), one Fe(3), two equivalent Fe(1), and two equivalent Fe(2) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to three Nb(1,1); three Nb(2,2); two equivalent Cr(2); one Fe(1); one Fe(3); and two equivalent Fe(2) atoms to form distorted CrNb6Cr2Fe4 cuboctahedra that share corners with two equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, corners with two equivalent Fe(1)Nb6Cr6 cuboctahedra, corners with four equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, corners with four equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, edges with six equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, faces with two equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, faces with three equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, faces with three equivalent Fe(1)Nb6Cr6 cuboctahedra, faces with six equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, and faces with six equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra. In the second Cr site, Cr(2) is bonded to two Nb(2,2); four Nb(1,1,1); two equivalent Cr(1); two equivalent Cr(2); and two equivalent Fe(1) atoms to form distorted CrNb6Cr4Fe2 cuboctahedra that share corners with four equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, corners with four equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, corners with six equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, edges with two equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, edges with four equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, faces with two equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, faces with two equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, faces with four equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, faces with four equivalent Fe(1)Nb6Cr6 cuboctahedra, and faces with six equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two Nb(2,2); four equivalent Nb(1); two equivalent Cr(1); and four equivalent Cr(2) atoms to form FeNb6Cr6 cuboctahedra that share corners with two equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Fe(1)Nb6Cr6 cuboctahedra, corners with eight equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, edges with two equivalent Fe(1)Nb6Cr6 cuboctahedra, edges with four equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, faces with four equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, faces with six equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, and faces with eight equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra. In the second Fe site, Fe(2) is bonded to two equivalent Nb(1); four Nb(2,2,2); two equivalent Cr(1); two equivalent Fe(2); and two equivalent Fe(3) atoms to form distorted FeNb6Cr2Fe4 cuboctahedra that share corners with four equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Fe(1)Nb6Cr6 cuboctahedra, corners with six equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, edges with two equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, edges with four equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, faces with two equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, faces with two equivalent Fe(1)Nb6Cr6 cuboctahedra, faces with four equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, faces with four equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, and faces with six equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra. In the third Fe site, Fe(3) is bonded to two equivalent Nb(1); four Nb(2,2); two equivalent Cr(1); and four equivalent Fe(2) atoms to form distorted FeNb6Cr2Fe4 cuboctahedra that share corners with two equivalent Fe(1)Nb6Cr6 cuboctahedra, corners with four equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, corners with eight equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, edges with two equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, edges with four equivalent Fe(1)Nb6Cr6 cuboctahedra, faces with four equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, faces with six equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, and faces with eight equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra.
CrFeNb crystallizes in the orthorhombic Amm2 space group. There are six inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1); three Nb(2,2); three equivalent Cr(1); four equivalent Cr(2); one Fe(3); two equivalent Fe(1); and two equivalent Fe(2) atoms. The Nb(1)-Nb(1) bond length is 3.00 Å. There are two shorter (2.96 Å) and one longer (2.98 Å) Nb(1)-Nb(2,2) bond length. There are two shorter (2.84 Å) and one longer (2.88 Å) Nb(1)-Cr(1) bond length. There are two shorter (2.86 Å) and two longer (2.87 Å) Nb(1)-Cr(2) bond lengths. The Nb(1)-Fe(3) bond length is 2.76 Å. Both Nb(1)-Fe(1) bond lengths are 2.84 Å. Both Nb(1)-Fe(2) bond lengths are 2.76 Å. In the second Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(2); three Nb(1,1); two equivalent Cr(2); three equivalent Cr(1); one Fe(1); two equivalent Fe(3); and four equivalent Fe(2) atoms. The Nb(2)-Nb(2) bond length is 2.89 Å. The Nb(2)-Nb(1) bond length is 2.98 Å. Both Nb(2)-Cr(2) bond lengths are 2.81 Å. There are two shorter (2.83 Å) and one longer (2.86 Å) Nb(2)-Cr(1) bond length. The Nb(2)-Fe(1) bond length is 2.82 Å. Both Nb(2)-Fe(3) bond lengths are 2.81 Å. There are two shorter (2.83 Å) and two longer (2.85 Å) Nb(2)-Fe(2) bond lengths. In the third Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(2); three Nb(1,1); two equivalent Cr(2); three equivalent Cr(1); one Fe(1); two equivalent Fe(3); and four equivalent Fe(2) atoms. There are two shorter (2.96 Å) and one longer (2.98 Å) Nb(2)-Nb(1,1) bond length. Both Nb(2)-Cr(2) bond lengths are 2.81 Å. There are two shorter (2.83 Å) and one longer (2.86 Å) Nb(2)-Cr(1) bond length. The Nb(2)-Fe(1) bond length is 2.82 Å. Both Nb(2)-Fe(3) bond lengths are 2.81 Å. There are two shorter (2.83 Å) and two longer (2.85 Å) Nb(2)-Fe(2) bond lengths. In the fourth Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1); three Nb(2,2); three equivalent Cr(1); four equivalent Cr(2); one Fe(3); two equivalent Fe(1); and two equivalent Fe(2) atoms. The Nb(1)-Nb(1) bond length is 3.00 Å. Both Nb(1)-Nb(2) bond lengths are 2.96 Å. There are two shorter (2.84 Å) and one longer (2.88 Å) Nb(1)-Cr(1) bond length. There are two shorter (2.86 Å) and two longer (2.87 Å) Nb(1)-Cr(2) bond lengths. The Nb(1)-Fe(3) bond length is 2.76 Å. Both Nb(1)-Fe(1) bond lengths are 2.84 Å. Both Nb(1)-Fe(2) bond lengths are 2.76 Å. In the fifth Nb site, Nb(2) is bonded in a 16-coordinate geometry to one Nb(2); three Nb(1,1); two equivalent Cr(2); three equivalent Cr(1); one Fe(1); two equivalent Fe(3); and four equivalent Fe(2) atoms. The Nb(2)-Nb(2) bond length is 2.89 Å. Both Nb(2)-Cr(2) bond lengths are 2.81 Å. There are two shorter (2.83 Å) and one longer (2.86 Å) Nb(2)-Cr(1) bond length. The Nb(2)-Fe(1) bond length is 2.82 Å. Both Nb(2)-Fe(3) bond lengths are 2.81 Å. There are two shorter (2.83 Å) and two longer (2.85 Å) Nb(2)-Fe(2) bond lengths. In the sixth Nb site, Nb(1) is bonded in a 16-coordinate geometry to one Nb(1), three equivalent Nb(2), three equivalent Cr(1), four equivalent Cr(2), one Fe(3), two equivalent Fe(1), and two equivalent Fe(2) atoms. There are two shorter (2.84 Å) and one longer (2.88 Å) Nb(1)-Cr(1) bond length. There are two shorter (2.86 Å) and two longer (2.87 Å) Nb(1)-Cr(2) bond lengths. The Nb(1)-Fe(3) bond length is 2.76 Å. Both Nb(1)-Fe(1) bond lengths are 2.84 Å. Both Nb(1)-Fe(2) bond lengths are 2.76 Å. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to three Nb(1,1); three Nb(2,2); two equivalent Cr(2); one Fe(1); one Fe(3); and two equivalent Fe(2) atoms to form distorted CrNb6Cr2Fe4 cuboctahedra that share corners with two equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, corners with two equivalent Fe(1)Nb6Cr6 cuboctahedra, corners with four equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, corners with four equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, edges with six equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, faces with two equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, faces with three equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, faces with three equivalent Fe(1)Nb6Cr6 cuboctahedra, faces with six equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, and faces with six equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra. Both Cr(1)-Cr(2) bond lengths are 2.48 Å. The Cr(1)-Fe(1) bond length is 2.48 Å. The Cr(1)-Fe(3) bond length is 2.39 Å. Both Cr(1)-Fe(2) bond lengths are 2.36 Å. In the second Cr site, Cr(2) is bonded to two Nb(2,2); four Nb(1,1,1); two equivalent Cr(1); two equivalent Cr(2); and two equivalent Fe(1) atoms to form distorted CrNb6Cr4Fe2 cuboctahedra that share corners with four equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, corners with four equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, corners with six equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, edges with two equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, edges with four equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, faces with two equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, faces with two equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, faces with four equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, faces with four equivalent Fe(1)Nb6Cr6 cuboctahedra, and faces with six equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra. There is one shorter (2.36 Å) and one longer (2.47 Å) Cr(2)-Cr(2) bond length. There is one shorter (2.38 Å) and one longer (2.51 Å) Cr(2)-Fe(1) bond length. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two Nb(2,2); four equivalent Nb(1); two equivalent Cr(1); and four equivalent Cr(2) atoms to form FeNb6Cr6 cuboctahedra that share corners with two equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Fe(1)Nb6Cr6 cuboctahedra, corners with eight equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, edges with two equivalent Fe(1)Nb6Cr6 cuboctahedra, edges with four equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, faces with four equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, faces with six equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, and faces with eight equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra. In the second Fe site, Fe(2) is bonded to two equivalent Nb(1); four Nb(2,2,2); two equivalent Cr(1); two equivalent Fe(2); and two equivalent Fe(3) atoms to form distorted FeNb6Cr2Fe4 cuboctahedra that share corners with four equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Fe(1)Nb6Cr6 cuboctahedra, corners with six equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, edges with two equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, edges with four equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, faces with two equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, faces with two equivalent Fe(1)Nb6Cr6 cuboctahedra, faces with four equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra, faces with four equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, and faces with six equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra. There is one shorter (2.35 Å) and one longer (2.48 Å) Fe(2)-Fe(2) bond length. There is one shorter (2.37 Å) and one longer (2.51 Å) Fe(2)-Fe(3) bond length. In the third Fe site, Fe(3) is bonded to two equivalent Nb(1); four Nb(2,2); two equivalent Cr(1); and four equivalent Fe(2) atoms to form distorted FeNb6Cr2Fe4 cuboctahedra that share corners with two equivalent Fe(1)Nb6Cr6 cuboctahedra, corners with four equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, corners with four equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, corners with eight equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, edges with two equivalent Fe(3)Nb6Cr2Fe4 cuboctahedra, edges with four equivalent Fe(1)Nb6Cr6 cuboctahedra, faces with four equivalent Cr(2)Nb6Cr4Fe2 cuboctahedra, faces with six equivalent Cr(1)Nb6Cr2Fe4 cuboctahedra, and faces with eight equivalent Fe(2)Nb6Cr2Fe4 cuboctahedra.