Eu3Sm3S8 crystallizes in the monoclinic C2 space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms to form distorted EuS8 hexagonal bipyramids that share corners with four equivalent Eu(2)S8 hexagonal bipyramids, corners with four equivalent Sm(1)S8 hexagonal bipyramids, edges with four equivalent Sm(2)S8 hexagonal bipyramids, faces with four equivalent Eu(2)S8 hexagonal bipyramids, and faces with four equivalent Sm(1)S8 hexagonal bipyramids. In the second Eu site, Eu(2) is bonded to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms to form distorted EuS8 hexagonal bipyramids that share corners with two equivalent Eu(1)S8 hexagonal bipyramids, corners with two equivalent Sm(2)S8 hexagonal bipyramids, corners with four equivalent Sm(1)S8 hexagonal bipyramids, edges with four equivalent Eu(2)S8 hexagonal bipyramids, faces with two equivalent Eu(1)S8 hexagonal bipyramids, faces with two equivalent Sm(2)S8 hexagonal bipyramids, and faces with four equivalent Sm(1)S8 hexagonal bipyramids. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms to form distorted SmS8 hexagonal bipyramids that share corners with two equivalent Eu(1)S8 hexagonal bipyramids, corners with two equivalent Sm(2)S8 hexagonal bipyramids, corners with four equivalent Eu(2)S8 hexagonal bipyramids, edges with four equivalent Sm(1)S8 hexagonal bipyramids, faces with two equivalent Eu(1)S8 hexagonal bipyramids, faces with two equivalent Sm(2)S8 hexagonal bipyramids, and faces with four equivalent Eu(2)S8 hexagonal bipyramids. In the second Sm site, Sm(2) is bonded to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms to form distorted SmS8 hexagonal bipyramids that share corners with four equivalent Eu(2)S8 hexagonal bipyramids, corners with four equivalent Sm(1)S8 hexagonal bipyramids, edges with four equivalent Eu(1)S8 hexagonal bipyramids, faces with four equivalent Eu(2)S8 hexagonal bipyramids, and faces with four equivalent Sm(1)S8 hexagonal bipyramids. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Eu(1), two equivalent Eu(2), one Sm(2), and two equivalent Sm(1) atoms to form a mixture of distorted edge, corner, and face-sharing SSm3Eu3 octahedra. The corner-sharing octahedral tilt angles range from 16-50°. In the second S site, S(2) is bonded to one Eu(1), two equivalent Eu(2), one Sm(2), and two equivalent Sm(1) atoms to form a mixture of distorted edge, corner, and face-sharing SSm3Eu3 octahedra. The corner-sharing octahedral tilt angles range from 17-50°. In the third S site, S(3) is bonded to one Eu(1), two equivalent Eu(2), one Sm(2), and two equivalent Sm(1) atoms to form a mixture of distorted edge, corner, and face-sharing SSm3Eu3 octahedra. The corner-sharing octahedral tilt angles range from 18-50°. In the fourth S site, S(4) is bonded to one Eu(1), two equivalent Eu(2), one Sm(2), and two equivalent Sm(1) atoms to form a mixture of distorted edge, corner, and face-sharing SSm3Eu3 octahedra. The corner-sharing octahedral tilt angles range from 17-50°.
Eu3Sm3S8 crystallizes in the monoclinic C2 space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms to form distorted EuS8 hexagonal bipyramids that share corners with four equivalent Eu(2)S8 hexagonal bipyramids, corners with four equivalent Sm(1)S8 hexagonal bipyramids, edges with four equivalent Sm(2)S8 hexagonal bipyramids, faces with four equivalent Eu(2)S8 hexagonal bipyramids, and faces with four equivalent Sm(1)S8 hexagonal bipyramids. Both Eu(1)-S(1) bond lengths are 2.91 Å. Both Eu(1)-S(2) bond lengths are 2.87 Å. Both Eu(1)-S(3) bond lengths are 3.10 Å. Both Eu(1)-S(4) bond lengths are 3.11 Å. In the second Eu site, Eu(2) is bonded to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms to form distorted EuS8 hexagonal bipyramids that share corners with two equivalent Eu(1)S8 hexagonal bipyramids, corners with two equivalent Sm(2)S8 hexagonal bipyramids, corners with four equivalent Sm(1)S8 hexagonal bipyramids, edges with four equivalent Eu(2)S8 hexagonal bipyramids, faces with two equivalent Eu(1)S8 hexagonal bipyramids, faces with two equivalent Sm(2)S8 hexagonal bipyramids, and faces with four equivalent Sm(1)S8 hexagonal bipyramids. There is one shorter (2.89 Å) and one longer (3.08 Å) Eu(2)-S(1) bond length. There is one shorter (2.90 Å) and one longer (3.08 Å) Eu(2)-S(2) bond length. There is one shorter (2.87 Å) and one longer (3.09 Å) Eu(2)-S(3) bond length. There is one shorter (2.90 Å) and one longer (3.11 Å) Eu(2)-S(4) bond length. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms to form distorted SmS8 hexagonal bipyramids that share corners with two equivalent Eu(1)S8 hexagonal bipyramids, corners with two equivalent Sm(2)S8 hexagonal bipyramids, corners with four equivalent Eu(2)S8 hexagonal bipyramids, edges with four equivalent Sm(1)S8 hexagonal bipyramids, faces with two equivalent Eu(1)S8 hexagonal bipyramids, faces with two equivalent Sm(2)S8 hexagonal bipyramids, and faces with four equivalent Eu(2)S8 hexagonal bipyramids. There is one shorter (2.84 Å) and one longer (3.03 Å) Sm(1)-S(1) bond length. There is one shorter (2.86 Å) and one longer (3.06 Å) Sm(1)-S(2) bond length. There is one shorter (2.83 Å) and one longer (3.10 Å) Sm(1)-S(3) bond length. There is one shorter (2.84 Å) and one longer (3.06 Å) Sm(1)-S(4) bond length. In the second Sm site, Sm(2) is bonded to two equivalent S(1), two equivalent S(2), two equivalent S(3), and two equivalent S(4) atoms to form distorted SmS8 hexagonal bipyramids that share corners with four equivalent Eu(2)S8 hexagonal bipyramids, corners with four equivalent Sm(1)S8 hexagonal bipyramids, edges with four equivalent Eu(1)S8 hexagonal bipyramids, faces with four equivalent Eu(2)S8 hexagonal bipyramids, and faces with four equivalent Sm(1)S8 hexagonal bipyramids. Both Sm(2)-S(1) bond lengths are 3.05 Å. Both Sm(2)-S(2) bond lengths are 3.05 Å. Both Sm(2)-S(3) bond lengths are 2.86 Å. Both Sm(2)-S(4) bond lengths are 2.82 Å. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Eu(1), two equivalent Eu(2), one Sm(2), and two equivalent Sm(1) atoms to form a mixture of distorted edge, corner, and face-sharing SSm3Eu3 octahedra. The corner-sharing octahedral tilt angles range from 16-50°. In the second S site, S(2) is bonded to one Eu(1), two equivalent Eu(2), one Sm(2), and two equivalent Sm(1) atoms to form a mixture of distorted edge, corner, and face-sharing SSm3Eu3 octahedra. The corner-sharing octahedral tilt angles range from 17-50°. In the third S site, S(3) is bonded to one Eu(1), two equivalent Eu(2), one Sm(2), and two equivalent Sm(1) atoms to form a mixture of distorted edge, corner, and face-sharing SSm3Eu3 octahedra. The corner-sharing octahedral tilt angles range from 18-50°. In the fourth S site, S(4) is bonded to one Eu(1), two equivalent Eu(2), one Sm(2), and two equivalent Sm(1) atoms to form a mixture of distorted edge, corner, and face-sharing SSm3Eu3 octahedra. The corner-sharing octahedral tilt angles range from 17-50°.