Nb2CuTe4 crystallizes in the monoclinic Pm space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one Cu(1), one Te(1), one Te(3), two equivalent Te(2), and two equivalent Te(4) atoms. In the second Nb site, Nb(2) is bonded in a 6-coordinate geometry to one Te(2), one Te(4), two equivalent Te(1), and two equivalent Te(3) atoms. Cu(1) is bonded in a 5-coordinate geometry to one Nb(1), one Te(1), one Te(3), and two equivalent Te(4) atoms. There are four inequivalent Te sites. In the first Te site, Te(1) is bonded in a 4-coordinate geometry to one Nb(1), two equivalent Nb(2), and one Cu(1) atom. In the second Te site, Te(2) is bonded in a distorted T-shaped geometry to one Nb(2) and two equivalent Nb(1) atoms. In the third Te site, Te(3) is bonded to one Nb(1), two equivalent Nb(2), and one Cu(1) atom to form distorted corner-sharing TeNb3Cu tetrahedra. In the fourth Te site, Te(4) is bonded in a 5-coordinate geometry to one Nb(2), two equivalent Nb(1), and two equivalent Cu(1) atoms.
Nb2CuTe4 crystallizes in the monoclinic Pm space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 6-coordinate geometry to one Cu(1), one Te(1), one Te(3), two equivalent Te(2), and two equivalent Te(4) atoms. The Nb(1)-Cu(1) bond length is 3.02 Å. The Nb(1)-Te(1) bond length is 2.81 Å. The Nb(1)-Te(3) bond length is 3.00 Å. Both Nb(1)-Te(2) bond lengths are 2.78 Å. Both Nb(1)-Te(4) bond lengths are 2.90 Å. In the second Nb site, Nb(2) is bonded in a 6-coordinate geometry to one Te(2), one Te(4), two equivalent Te(1), and two equivalent Te(3) atoms. The Nb(2)-Te(2) bond length is 2.75 Å. The Nb(2)-Te(4) bond length is 2.96 Å. Both Nb(2)-Te(1) bond lengths are 2.77 Å. Both Nb(2)-Te(3) bond lengths are 2.91 Å. Cu(1) is bonded in a 5-coordinate geometry to one Nb(1), one Te(1), one Te(3), and two equivalent Te(4) atoms. The Cu(1)-Te(1) bond length is 2.61 Å. The Cu(1)-Te(3) bond length is 2.58 Å. Both Cu(1)-Te(4) bond lengths are 2.62 Å. There are four inequivalent Te sites. In the first Te site, Te(1) is bonded in a 4-coordinate geometry to one Nb(1), two equivalent Nb(2), and one Cu(1) atom. In the second Te site, Te(2) is bonded in a distorted T-shaped geometry to one Nb(2) and two equivalent Nb(1) atoms. In the third Te site, Te(3) is bonded to one Nb(1), two equivalent Nb(2), and one Cu(1) atom to form distorted corner-sharing TeNb3Cu tetrahedra. In the fourth Te site, Te(4) is bonded in a 5-coordinate geometry to one Nb(2), two equivalent Nb(1), and two equivalent Cu(1) atoms.