HfCrCuS4 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 7-coordinate geometry to one S(3), one S(5), one S(6), two equivalent S(1), and two equivalent S(2) atoms. In the second Hf site, Hf(2) is bonded in a 4-coordinate geometry to one S(4), one S(6), two equivalent S(1), and two equivalent S(2) atoms. There are two 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 distorted CrS6 octahedra that share corners with three equivalent Cu(2)S4 tetrahedra. In the second Cr site, Cr(2) is bonded in a rectangular see-saw-like geometry to one S(3), one S(5), and two equivalent S(2) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 4-coordinate geometry to one S(3), one S(5), 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 distorted CuS4 tetrahedra that share corners with three equivalent Cr(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 15-62°. There are six inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to one Hf(1), one Hf(2), one Cr(1), and one Cu(1) atom. In the second S site, S(2) is bonded in a 5-coordinate geometry to one Hf(1), one Hf(2), one Cr(1), one Cr(2), and one Cu(2) atom. In the third S site, S(3) is bonded in a 3-coordinate geometry to one Hf(1), one Cr(2), and one Cu(1) atom. In the fourth S site, S(4) is bonded in a distorted bent 150 degrees geometry to one Hf(2) and one Cu(2) atom. In the fifth S site, S(5) is bonded in a rectangular see-saw-like geometry to one Hf(1), one Cr(1), one Cr(2), and one Cu(1) atom. In the sixth S site, S(6) is bonded in a rectangular see-saw-like geometry to one Hf(1), one Hf(2), one Cr(1), and one Cu(2) atom.
HfCrCuS4 crystallizes in the orthorhombic Pmn2_1 space group. There are two inequivalent Hf sites. In the first Hf site, Hf(1) is bonded in a 7-coordinate geometry to one S(3), one S(5), one S(6), two equivalent S(1), and two equivalent S(2) atoms. The Hf(1)-S(3) bond length is 2.67 Å. The Hf(1)-S(5) bond length is 2.43 Å. The Hf(1)-S(6) bond length is 2.78 Å. Both Hf(1)-S(1) bond lengths are 2.76 Å. Both Hf(1)-S(2) bond lengths are 2.60 Å. In the second Hf site, Hf(2) is bonded in a 4-coordinate geometry to one S(4), one S(6), two equivalent S(1), and two equivalent S(2) atoms. The Hf(2)-S(4) bond length is 2.33 Å. The Hf(2)-S(6) bond length is 2.50 Å. Both Hf(2)-S(1) bond lengths are 2.47 Å. Both Hf(2)-S(2) bond lengths are 3.24 Å. There are two 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 distorted CrS6 octahedra that share corners with three equivalent Cu(2)S4 tetrahedra. The Cr(1)-S(5) bond length is 2.38 Å. The Cr(1)-S(6) bond length is 2.39 Å. Both Cr(1)-S(1) bond lengths are 2.43 Å. Both Cr(1)-S(2) bond lengths are 2.53 Å. In the second Cr site, Cr(2) is bonded in a rectangular see-saw-like geometry to one S(3), one S(5), and two equivalent S(2) atoms. The Cr(2)-S(3) bond length is 2.17 Å. The Cr(2)-S(5) bond length is 2.26 Å. Both Cr(2)-S(2) bond lengths are 2.33 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 4-coordinate geometry to one S(3), one S(5), and two equivalent S(1) atoms. The Cu(1)-S(3) bond length is 2.32 Å. The Cu(1)-S(5) bond length is 2.54 Å. Both Cu(1)-S(1) bond lengths are 2.25 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 distorted CuS4 tetrahedra that share corners with three equivalent Cr(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 15-62°. The Cu(2)-S(4) bond length is 2.23 Å. The Cu(2)-S(6) bond length is 2.32 Å. Both Cu(2)-S(2) bond lengths are 2.36 Å. There are six inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to one Hf(1), one Hf(2), one Cr(1), and one Cu(1) atom. In the second S site, S(2) is bonded in a 5-coordinate geometry to one Hf(1), one Hf(2), one Cr(1), one Cr(2), and one Cu(2) atom. In the third S site, S(3) is bonded in a 3-coordinate geometry to one Hf(1), one Cr(2), and one Cu(1) atom. In the fourth S site, S(4) is bonded in a distorted bent 150 degrees geometry to one Hf(2) and one Cu(2) atom. In the fifth S site, S(5) is bonded in a rectangular see-saw-like geometry to one Hf(1), one Cr(1), one Cr(2), and one Cu(1) atom. In the sixth S site, S(6) is bonded in a rectangular see-saw-like geometry to one Hf(1), one Hf(2), one Cr(1), and one Cu(2) atom.