BaCr4S7 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 11-coordinate geometry to one S(2), one S(4), one S(6), two equivalent S(3), three equivalent S(5), and three equivalent S(7) atoms. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(1), one S(3), one S(4), one S(5), one S(6), and one S(7) atom to form a mixture of face, corner, and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles range from 22-51°. In the second Cr site, Cr(2) is bonded to two equivalent S(3), two equivalent S(5), and two equivalent S(7) atoms to form a mixture of face, corner, and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles are 22°. In the third Cr site, Cr(3) is bonded to one S(1), one S(6), two equivalent S(2), and two equivalent S(4) atoms to form a mixture of corner and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles range from 46-49°. In the fourth Cr site, Cr(4) is bonded to one S(2), one S(4), two equivalent S(1), and two equivalent S(6) atoms to form a mixture of face, corner, and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles range from 47-51°. There are seven inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to one Cr(1), one Cr(3), and two equivalent Cr(4) atoms. In the second S site, S(2) is bonded in a rectangular see-saw-like geometry to one Ba(1), one Cr(4), and two equivalent Cr(3) atoms. In the third S site, S(3) is bonded to two equivalent Ba(1), one Cr(1), and two equivalent Cr(2) atoms to form distorted SBa2Cr3 square pyramids that share corners with four equivalent S(3)Ba2Cr3 square pyramids,  a cornercorner with one S(6)BaCr4 trigonal bipyramid, and  an edgeedge with one S(6)BaCr4 trigonal bipyramid. In the fourth S site, S(4) is bonded in a 5-coordinate geometry to one Ba(1), one Cr(1), one Cr(4), and two equivalent Cr(3) atoms. In the fifth S site, S(5) is bonded in a 6-coordinate geometry to three equivalent Ba(1), one Cr(1), and two equivalent Cr(2) atoms. In the sixth S site, S(6) is bonded to one Ba(1), one Cr(1), one Cr(3), and two equivalent Cr(4) atoms to form distorted SBaCr4 trigonal bipyramids that share  a cornercorner with one S(3)Ba2Cr3 square pyramid,  an edgeedge with one S(3)Ba2Cr3 square pyramid, and  an edgeedge with one S(6)BaCr4 trigonal bipyramid. In the seventh S site, S(7) is bonded in a 6-coordinate geometry to three equivalent Ba(1), one Cr(1), and two equivalent Cr(2) atoms.
BaCr4S7 crystallizes in the monoclinic P2_1/c space group. Ba(1) is bonded in a 11-coordinate geometry to one S(2), one S(4), one S(6), two equivalent S(3), three equivalent S(5), and three equivalent S(7) atoms. The Ba(1)-S(2) bond length is 3.19 Å. The Ba(1)-S(4) bond length is 3.40 Å. The Ba(1)-S(6) bond length is 3.35 Å. There is one shorter (3.41 Å) and one longer (3.42 Å) Ba(1)-S(3) bond length. There are a spread of Ba(1)-S(5) bond distances ranging from 3.45-3.72 Å. There are two shorter (3.44 Å) and one longer (3.71 Å) Ba(1)-S(7) bond length. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one S(1), one S(3), one S(4), one S(5), one S(6), and one S(7) atom to form a mixture of face, corner, and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles range from 22-51°. The Cr(1)-S(1) bond length is 2.44 Å. The Cr(1)-S(3) bond length is 2.39 Å. The Cr(1)-S(4) bond length is 2.50 Å. The Cr(1)-S(5) bond length is 2.44 Å. The Cr(1)-S(6) bond length is 2.47 Å. The Cr(1)-S(7) bond length is 2.44 Å. In the second Cr site, Cr(2) is bonded to two equivalent S(3), two equivalent S(5), and two equivalent S(7) atoms to form a mixture of face, corner, and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles are 22°. There is one shorter (2.37 Å) and one longer (2.39 Å) Cr(2)-S(3) bond length. There is one shorter (2.42 Å) and one longer (2.48 Å) Cr(2)-S(5) bond length. There is one shorter (2.43 Å) and one longer (2.48 Å) Cr(2)-S(7) bond length. In the third Cr site, Cr(3) is bonded to one S(1), one S(6), two equivalent S(2), and two equivalent S(4) atoms to form a mixture of corner and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles range from 46-49°. The Cr(3)-S(1) bond length is 2.39 Å. The Cr(3)-S(6) bond length is 2.43 Å. There is one shorter (2.35 Å) and one longer (2.36 Å) Cr(3)-S(2) bond length. There is one shorter (2.42 Å) and one longer (2.45 Å) Cr(3)-S(4) bond length. In the fourth Cr site, Cr(4) is bonded to one S(2), one S(4), two equivalent S(1), and two equivalent S(6) atoms to form a mixture of face, corner, and edge-sharing CrS6 octahedra. The corner-sharing octahedral tilt angles range from 47-51°. The Cr(4)-S(2) bond length is 2.33 Å. The Cr(4)-S(4) bond length is 2.45 Å. There is one shorter (2.36 Å) and one longer (2.41 Å) Cr(4)-S(1) bond length. There is one shorter (2.41 Å) and one longer (2.47 Å) Cr(4)-S(6) bond length. There are seven inequivalent S sites. In the first S site, S(1) is bonded in a rectangular see-saw-like geometry to one Cr(1), one Cr(3), and two equivalent Cr(4) atoms. In the second S site, S(2) is bonded in a rectangular see-saw-like geometry to one Ba(1), one Cr(4), and two equivalent Cr(3) atoms. In the third S site, S(3) is bonded to two equivalent Ba(1), one Cr(1), and two equivalent Cr(2) atoms to form distorted SBa2Cr3 square pyramids that share corners with four equivalent S(3)Ba2Cr3 square pyramids,  a cornercorner with one S(6)BaCr4 trigonal bipyramid, and  an edgeedge with one S(6)BaCr4 trigonal bipyramid. In the fourth S site, S(4) is bonded in a 5-coordinate geometry to one Ba(1), one Cr(1), one Cr(4), and two equivalent Cr(3) atoms. In the fifth S site, S(5) is bonded in a 6-coordinate geometry to three equivalent Ba(1), one Cr(1), and two equivalent Cr(2) atoms. In the sixth S site, S(6) is bonded to one Ba(1), one Cr(1), one Cr(3), and two equivalent Cr(4) atoms to form distorted SBaCr4 trigonal bipyramids that share  a cornercorner with one S(3)Ba2Cr3 square pyramid,  an edgeedge with one S(3)Ba2Cr3 square pyramid, and  an edgeedge with one S(6)BaCr4 trigonal bipyramid. In the seventh S site, S(7) is bonded in a 6-coordinate geometry to three equivalent Ba(1), one Cr(1), and two equivalent Cr(2) atoms.