NbCr3(CuS4)2 crystallizes in the orthorhombic Pmn2_1 space group. Nb(1) is bonded in a 6-coordinate geometry to one S(3), one S(5), two equivalent S(1), and two equivalent S(2) atoms. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(5), one S(6), two equivalent S(1), and two equivalent S(2) atoms to form CrS6 octahedra that share  a cornercorner with one Cr(2)S4 tetrahedra, corners with three equivalent Cu(2)S4 tetrahedra, and  an edgeedge with one Cr(2)S4 tetrahedra. In the second Cr site, Cr(2) is bonded to one S(4), one S(6), and two equivalent S(1) atoms to form distorted CrS4 tetrahedra that share  a cornercorner with one Cr(1)S6 octahedra, corners with two equivalent Cu(2)S4 tetrahedra, and  an edgeedge with one Cr(1)S6 octahedra. The corner-sharing octahedral tilt angles are 46°. In the third Cr site, Cr(3) is bonded in a 2-coordinate geometry to one S(3) and one S(5) atom. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 3-coordinate geometry to one S(3) and two equivalent S(1) atoms. In the second Cu site, Cu(2) is bonded to one S(4), one S(6), and two equivalent S(2) atoms to form CuS4 tetrahedra that share corners with three equivalent Cr(1)S6 octahedra and corners with two equivalent Cr(2)S4 tetrahedra. The corner-sharing octahedral tilt angles range from 19-60°. There are six inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Nb(1), one Cr(1), one Cr(2), and one Cu(1) atom. In the second S site, S(2) is bonded in a distorted T-shaped geometry to one Nb(1), one Cr(1), and one Cu(2) atom. In the third S site, S(3) is bonded in a distorted trigonal planar geometry to one Nb(1), one Cr(3), and one Cu(1) atom. In the fourth S site, S(4) is bonded in a bent 120 degrees geometry to one Cr(2) and one Cu(2) atom. In the fifth S site, S(5) is bonded in a 3-coordinate geometry to one Nb(1), one Cr(1), and one Cr(3) atom. In the sixth S site, S(6) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cr(2), and one Cu(2) atom.
NbCr3(CuS4)2 crystallizes in the orthorhombic Pmn2_1 space group. Nb(1) is bonded in a 6-coordinate geometry to one S(3), one S(5), two equivalent S(1), and two equivalent S(2) atoms. The Nb(1)-S(3) bond length is 2.42 Å. The Nb(1)-S(5) bond length is 2.46 Å. Both Nb(1)-S(1) bond lengths are 2.79 Å. Both Nb(1)-S(2) bond lengths are 2.34 Å. There are three inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(5), one S(6), two equivalent S(1), and two equivalent S(2) atoms to form CrS6 octahedra that share  a cornercorner with one Cr(2)S4 tetrahedra, corners with three equivalent Cu(2)S4 tetrahedra, and  an edgeedge with one Cr(2)S4 tetrahedra. The Cr(1)-S(5) bond length is 2.31 Å. The Cr(1)-S(6) bond length is 2.54 Å. Both Cr(1)-S(1) bond lengths are 2.48 Å. Both Cr(1)-S(2) bond lengths are 2.41 Å. In the second Cr site, Cr(2) is bonded to one S(4), one S(6), and two equivalent S(1) atoms to form distorted CrS4 tetrahedra that share  a cornercorner with one Cr(1)S6 octahedra, corners with two equivalent Cu(2)S4 tetrahedra, and  an edgeedge with one Cr(1)S6 octahedra. The corner-sharing octahedral tilt angles are 46°. The Cr(2)-S(4) bond length is 2.11 Å. The Cr(2)-S(6) bond length is 2.18 Å. Both Cr(2)-S(1) bond lengths are 2.23 Å. In the third Cr site, Cr(3) is bonded in a 2-coordinate geometry to one S(3) and one S(5) atom. The Cr(3)-S(3) bond length is 2.24 Å. The Cr(3)-S(5) bond length is 2.24 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 3-coordinate geometry to one S(3) and two equivalent S(1) atoms. The Cu(1)-S(3) bond length is 2.29 Å. Both Cu(1)-S(1) bond lengths are 2.20 Å. In the second Cu site, Cu(2) is bonded to one S(4), one S(6), and two equivalent S(2) atoms to form CuS4 tetrahedra that share corners with three equivalent Cr(1)S6 octahedra and corners with two equivalent Cr(2)S4 tetrahedra. The corner-sharing octahedral tilt angles range from 19-60°. The Cu(2)-S(4) bond length is 2.27 Å. The Cu(2)-S(6) bond length is 2.22 Å. Both Cu(2)-S(2) bond lengths are 2.32 Å. There are six inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Nb(1), one Cr(1), one Cr(2), and one Cu(1) atom. In the second S site, S(2) is bonded in a distorted T-shaped geometry to one Nb(1), one Cr(1), and one Cu(2) atom. In the third S site, S(3) is bonded in a distorted trigonal planar geometry to one Nb(1), one Cr(3), and one Cu(1) atom. In the fourth S site, S(4) is bonded in a bent 120 degrees geometry to one Cr(2) and one Cu(2) atom. In the fifth S site, S(5) is bonded in a 3-coordinate geometry to one Nb(1), one Cr(1), and one Cr(3) atom. In the sixth S site, S(6) is bonded in a distorted trigonal planar geometry to one Cr(1), one Cr(2), and one Cu(2) atom.