Cr2HgSe3S is Spinel-derived structured and crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one Se(2), two equivalent Se(1), two equivalent Se(3), and one S(1) atom to form CrSe5S octahedra that share corners with three equivalent Hg(1)Se2S2 tetrahedra, corners with three equivalent Hg(2)Se4 tetrahedra, edges with two equivalent Cr(1)Se5S octahedra, and edges with four equivalent Cr(2)Se4S2 octahedra. In the second Cr site, Cr(2) is bonded to one Se(1), one Se(3), two equivalent Se(2), and two equivalent S(1) atoms to form CrSe4S2 octahedra that share corners with three equivalent Hg(1)Se2S2 tetrahedra, corners with three equivalent Hg(2)Se4 tetrahedra, edges with two equivalent Cr(2)Se4S2 octahedra, and edges with four equivalent Cr(1)Se5S octahedra. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to two equivalent Se(1) and two equivalent S(1) atoms to form HgSe2S2 tetrahedra that share corners with six equivalent Cr(2)Se4S2 octahedra and corners with six equivalent Cr(1)Se5S octahedra. The corner-sharing octahedral tilt angles range from 57-63°. In the second Hg site, Hg(2) is bonded to two equivalent Se(2) and two equivalent Se(3) atoms to form HgSe4 tetrahedra that share corners with six equivalent Cr(2)Se4S2 octahedra and corners with six equivalent Cr(1)Se5S octahedra. The corner-sharing octahedral tilt angles range from 61-62°. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cr(2), two equivalent Cr(1), and one Hg(1) atom to form distorted SeCr3Hg trigonal pyramids that share corners with two equivalent S(1)Cr3Hg tetrahedra, corners with four equivalent Se(2)Cr3Hg tetrahedra, corners with five equivalent Se(3)Cr3Hg tetrahedra,  a cornercorner with one Se(1)Cr3Hg trigonal pyramid, edges with two equivalent S(1)Cr3Hg tetrahedra, and  an edgeedge with one Se(1)Cr3Hg trigonal pyramid. In the second Se site, Se(2) is bonded to one Cr(1), two equivalent Cr(2), and one Hg(2) atom to form distorted SeCr3Hg tetrahedra that share  a cornercorner with one Se(2)Cr3Hg tetrahedra, corners with two equivalent Se(3)Cr3Hg tetrahedra, corners with five equivalent S(1)Cr3Hg tetrahedra, corners with four equivalent Se(1)Cr3Hg trigonal pyramids,  an edgeedge with one Se(2)Cr3Hg tetrahedra, and edges with two equivalent Se(3)Cr3Hg tetrahedra. In the third Se site, Se(3) is bonded to one Cr(2), two equivalent Cr(1), and one Hg(2) atom to form distorted SeCr3Hg tetrahedra that share  a cornercorner with one Se(3)Cr3Hg tetrahedra, corners with two equivalent Se(2)Cr3Hg tetrahedra, corners with four equivalent S(1)Cr3Hg tetrahedra, corners with five equivalent Se(1)Cr3Hg trigonal pyramids,  an edgeedge with one Se(3)Cr3Hg tetrahedra, and edges with two equivalent Se(2)Cr3Hg tetrahedra. S(1) is bonded to one Cr(1), two equivalent Cr(2), and one Hg(1) atom to form distorted SCr3Hg tetrahedra that share  a cornercorner with one S(1)Cr3Hg tetrahedra, corners with four equivalent Se(3)Cr3Hg tetrahedra, corners with five equivalent Se(2)Cr3Hg tetrahedra, corners with two equivalent Se(1)Cr3Hg trigonal pyramids,  an edgeedge with one S(1)Cr3Hg tetrahedra, and edges with two equivalent Se(1)Cr3Hg trigonal pyramids.
Cr2HgSe3S is Spinel-derived structured and crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one Se(2), two equivalent Se(1), two equivalent Se(3), and one S(1) atom to form CrSe5S octahedra that share corners with three equivalent Hg(1)Se2S2 tetrahedra, corners with three equivalent Hg(2)Se4 tetrahedra, edges with two equivalent Cr(1)Se5S octahedra, and edges with four equivalent Cr(2)Se4S2 octahedra. The Cr(1)-Se(2) bond length is 2.56 Å. Both Cr(1)-Se(1) bond lengths are 2.54 Å. Both Cr(1)-Se(3) bond lengths are 2.54 Å. The Cr(1)-S(1) bond length is 2.45 Å. In the second Cr site, Cr(2) is bonded to one Se(1), one Se(3), two equivalent Se(2), and two equivalent S(1) atoms to form CrSe4S2 octahedra that share corners with three equivalent Hg(1)Se2S2 tetrahedra, corners with three equivalent Hg(2)Se4 tetrahedra, edges with two equivalent Cr(2)Se4S2 octahedra, and edges with four equivalent Cr(1)Se5S octahedra. The Cr(2)-Se(1) bond length is 2.54 Å. The Cr(2)-Se(3) bond length is 2.55 Å. Both Cr(2)-Se(2) bond lengths are 2.57 Å. Both Cr(2)-S(1) bond lengths are 2.46 Å. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded to two equivalent Se(1) and two equivalent S(1) atoms to form HgSe2S2 tetrahedra that share corners with six equivalent Cr(2)Se4S2 octahedra and corners with six equivalent Cr(1)Se5S octahedra. The corner-sharing octahedral tilt angles range from 57-63°. Both Hg(1)-Se(1) bond lengths are 2.69 Å. Both Hg(1)-S(1) bond lengths are 2.62 Å. In the second Hg site, Hg(2) is bonded to two equivalent Se(2) and two equivalent Se(3) atoms to form HgSe4 tetrahedra that share corners with six equivalent Cr(2)Se4S2 octahedra and corners with six equivalent Cr(1)Se5S octahedra. The corner-sharing octahedral tilt angles range from 61-62°. Both Hg(2)-Se(2) bond lengths are 2.65 Å. Both Hg(2)-Se(3) bond lengths are 2.64 Å. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cr(2), two equivalent Cr(1), and one Hg(1) atom to form distorted SeCr3Hg trigonal pyramids that share corners with two equivalent S(1)Cr3Hg tetrahedra, corners with four equivalent Se(2)Cr3Hg tetrahedra, corners with five equivalent Se(3)Cr3Hg tetrahedra,  a cornercorner with one Se(1)Cr3Hg trigonal pyramid, edges with two equivalent S(1)Cr3Hg tetrahedra, and  an edgeedge with one Se(1)Cr3Hg trigonal pyramid. In the second Se site, Se(2) is bonded to one Cr(1), two equivalent Cr(2), and one Hg(2) atom to form distorted SeCr3Hg tetrahedra that share  a cornercorner with one Se(2)Cr3Hg tetrahedra, corners with two equivalent Se(3)Cr3Hg tetrahedra, corners with five equivalent S(1)Cr3Hg tetrahedra, corners with four equivalent Se(1)Cr3Hg trigonal pyramids,  an edgeedge with one Se(2)Cr3Hg tetrahedra, and edges with two equivalent Se(3)Cr3Hg tetrahedra. In the third Se site, Se(3) is bonded to one Cr(2), two equivalent Cr(1), and one Hg(2) atom to form distorted SeCr3Hg tetrahedra that share  a cornercorner with one Se(3)Cr3Hg tetrahedra, corners with two equivalent Se(2)Cr3Hg tetrahedra, corners with four equivalent S(1)Cr3Hg tetrahedra, corners with five equivalent Se(1)Cr3Hg trigonal pyramids,  an edgeedge with one Se(3)Cr3Hg tetrahedra, and edges with two equivalent Se(2)Cr3Hg tetrahedra. S(1) is bonded to one Cr(1), two equivalent Cr(2), and one Hg(1) atom to form distorted SCr3Hg tetrahedra that share  a cornercorner with one S(1)Cr3Hg tetrahedra, corners with four equivalent Se(3)Cr3Hg tetrahedra, corners with five equivalent Se(2)Cr3Hg tetrahedra, corners with two equivalent Se(1)Cr3Hg trigonal pyramids,  an edgeedge with one S(1)Cr3Hg tetrahedra, and edges with two equivalent Se(1)Cr3Hg trigonal pyramids.