BaVSeS2 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent Se(1), two equivalent S(1), two equivalent S(3), and four equivalent S(2) atoms to form BaSe4S8 cuboctahedra that share corners with six equivalent Ba(1)Se4S8 cuboctahedra, corners with six equivalent V(1)Se2S4 octahedra, faces with two equivalent Ba(1)Se4S8 cuboctahedra, faces with six equivalent Ba(2)Se4S8 cuboctahedra, and faces with six equivalent V(1)Se2S4 octahedra. The corner-sharing octahedral tilt angles range from 12-18°. In the second Ba site, Ba(2) is bonded to four equivalent Se(1), two equivalent S(1), two equivalent S(3), and four equivalent S(2) atoms to form BaSe4S8 cuboctahedra that share corners with six equivalent Ba(2)Se4S8 cuboctahedra, corners with six equivalent V(1)Se2S4 octahedra, faces with two equivalent Ba(2)Se4S8 cuboctahedra, faces with six equivalent Ba(1)Se4S8 cuboctahedra, and faces with six equivalent V(1)Se2S4 octahedra. The corner-sharing octahedral tilt angles are 21°. V(1) is bonded to two equivalent Se(1), one S(1), one S(3), and two equivalent S(2) atoms to form distorted VSe2S4 octahedra that share corners with three equivalent Ba(1)Se4S8 cuboctahedra, corners with three equivalent Ba(2)Se4S8 cuboctahedra, faces with three equivalent Ba(1)Se4S8 cuboctahedra, faces with three equivalent Ba(2)Se4S8 cuboctahedra, and faces with two equivalent V(1)Se2S4 octahedra. Se(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent V(1) atoms to form a mixture of distorted face and corner-sharing SeBa4V2 octahedra. The corner-sharing octahedral tilt angles range from 1-71°. There are three inequivalent S sites. In the first S site, S(1) is bonded in a distorted L-shaped geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent V(1) atoms. In the second S site, S(2) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent V(1) atoms. In the third S site, S(3) is bonded in a 2-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent V(1) atoms.
BaVSeS2 crystallizes in the orthorhombic Amm2 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent Se(1), two equivalent S(1), two equivalent S(3), and four equivalent S(2) atoms to form BaSe4S8 cuboctahedra that share corners with six equivalent Ba(1)Se4S8 cuboctahedra, corners with six equivalent V(1)Se2S4 octahedra, faces with two equivalent Ba(1)Se4S8 cuboctahedra, faces with six equivalent Ba(2)Se4S8 cuboctahedra, and faces with six equivalent V(1)Se2S4 octahedra. The corner-sharing octahedral tilt angles range from 12-18°. All Ba(1)-Se(1) bond lengths are 3.47 Å. Both Ba(1)-S(1) bond lengths are 3.52 Å. Both Ba(1)-S(3) bond lengths are 3.52 Å. There are two shorter (3.39 Å) and two longer (3.54 Å) Ba(1)-S(2) bond lengths. In the second Ba site, Ba(2) is bonded to four equivalent Se(1), two equivalent S(1), two equivalent S(3), and four equivalent S(2) atoms to form BaSe4S8 cuboctahedra that share corners with six equivalent Ba(2)Se4S8 cuboctahedra, corners with six equivalent V(1)Se2S4 octahedra, faces with two equivalent Ba(2)Se4S8 cuboctahedra, faces with six equivalent Ba(1)Se4S8 cuboctahedra, and faces with six equivalent V(1)Se2S4 octahedra. The corner-sharing octahedral tilt angles are 21°. There are two shorter (3.42 Å) and two longer (3.51 Å) Ba(2)-Se(1) bond lengths. Both Ba(2)-S(1) bond lengths are 3.52 Å. Both Ba(2)-S(3) bond lengths are 3.51 Å. All Ba(2)-S(2) bond lengths are 3.50 Å. V(1) is bonded to two equivalent Se(1), one S(1), one S(3), and two equivalent S(2) atoms to form distorted VSe2S4 octahedra that share corners with three equivalent Ba(1)Se4S8 cuboctahedra, corners with three equivalent Ba(2)Se4S8 cuboctahedra, faces with three equivalent Ba(1)Se4S8 cuboctahedra, faces with three equivalent Ba(2)Se4S8 cuboctahedra, and faces with two equivalent V(1)Se2S4 octahedra. Both V(1)-Se(1) bond lengths are 2.61 Å. The V(1)-S(1) bond length is 2.38 Å. The V(1)-S(3) bond length is 2.34 Å. Both V(1)-S(2) bond lengths are 2.34 Å. Se(1) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent V(1) atoms to form a mixture of distorted face and corner-sharing SeBa4V2 octahedra. The corner-sharing octahedral tilt angles range from 1-71°. There are three inequivalent S sites. In the first S site, S(1) is bonded in a distorted L-shaped geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent V(1) atoms. In the second S site, S(2) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent V(1) atoms. In the third S site, S(3) is bonded in a 2-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent V(1) atoms.