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Materials Data on La5SmS8 by Materials Project

SmLa5S8 crystallizes in the tetragonal I-4 space group. The structure is three-dimensional. Sm2+ is bonded to eight S2- atoms to form distorted SmS8 hexagonal bipyramids that share corners with eight equivalent LaS8 hexagonal bipyramids, edges with four equivalent LaS8 hexagonal bipyramids, and faces with eight equivalent LaS8 hexagonal bipyramids. There are four shorter (2.90 Å) and four longer (3.06 Å) Sm–S bond lengths. There are two inequivalent La+2.80+ sites. In the first La+2.80+ site, La+2.80+ is bonded to eight S2- atoms to form distorted LaS8 hexagonal bipyramids that share corners with two equivalent SmS8 hexagonal bipyramids, corners with six LaS8 hexagonal bipyramids, edges with four equivalent LaS8 hexagonal bipyramids, faces with two equivalent SmS8 hexagonal bipyramids, and faces with six LaS8 hexagonal bipyramids. There are a spread of La–S bond distances ranging from 2.93–3.14 Å. In the second La+2.80+ site, La+2.80+ is bonded to eight S2- atoms to form distorted LaS8 hexagonal bipyramids that share corners with eight equivalent LaS8 hexagonal bipyramids, edges with four equivalent SmS8 hexagonal bipyramids, and faces with eight equivalent LaS8 hexagonal bipyramids. There are four shorter (2.95 Å) and four longer (3.10 Å) La–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to one Sm2+ and five La+2.80+ atoms to form a mixture of distorted corner, edge, and face-sharing SLa5Sm octahedra. The corner-sharing octahedra tilt angles range from 16–50°. In the second S2- site, S2- is bonded to one Sm2+ and five La+2.80+ atoms to form a mixture of distorted corner, edge, and face-sharing SLa5Sm octahedra. The corner-sharing octahedra tilt angles range from 17–50°.

36 MATERIALS SCIENCE↗

Materials Data on La2SmS4 by Materials Project

SmLa2S4 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. Sm2+ is bonded to eight equivalent S2- atoms to form distorted SmS8 hexagonal bipyramids that share corners with eight equivalent LaS8 hexagonal bipyramids, edges with four equivalent SmS8 hexagonal bipyramids, and faces with eight equivalent LaS8 hexagonal bipyramids. There are four shorter (2.89 Å) and four longer (3.06 Å) Sm–S bond lengths. La3+ is bonded to eight equivalent S2- atoms to form distorted LaS8 hexagonal bipyramids that share corners with four equivalent SmS8 hexagonal bipyramids, corners with four equivalent LaS8 hexagonal bipyramids, edges with four equivalent LaS8 hexagonal bipyramids, faces with four equivalent SmS8 hexagonal bipyramids, and faces with four equivalent LaS8 hexagonal bipyramids. There are a spread of La–S bond distances ranging from 2.90–3.15 Å. S2- is bonded in a 6-coordinate geometry to two equivalent Sm2+ and four equivalent La3+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on LaSmS2 by Materials Project

SmLaS2 is Zintl Phase-derived structured and crystallizes in the cubic F-43m space group. The structure is three-dimensional. Sm2+ is bonded to four equivalent La2+ and ten S2- atoms to form distorted SmLa4S10 tetrahedra that share corners with four equivalent SLa4Sm6 tetrahedra, corners with six equivalent SmLa4S10 tetrahedra, corners with twelve equivalent LaSm4S4 tetrahedra, edges with six equivalent SLa4Sm6 tetrahedra, faces with four equivalent LaSm4S4 tetrahedra, and faces with twelve equivalent SmLa4S10 tetrahedra. All Sm–La bond lengths are 3.08 Å. There are four shorter (3.08 Å) and six longer (3.55 Å) Sm–S bond lengths. La2+ is bonded to four equivalent Sm2+ and four equivalent S2- atoms to form distorted LaSm4S4 tetrahedra that share corners with twelve equivalent SmLa4S10 tetrahedra, corners with sixteen SSm4 tetrahedra, edges with six equivalent SSm4 tetrahedra, edges with twelve equivalent LaSm4S4 tetrahedra, faces with four equivalent SmLa4S10 tetrahedra, and faces with four equivalent SLa4Sm6 tetrahedra. All La–S bond lengths are 3.08 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to four equivalent Sm2+ atoms to form distorted SSm4 tetrahedra that share corners with four equivalent LaSm4S4 tetrahedra, corners with twenty-four SSm4 tetrahedra, edges with six equivalent LaSm4S4 tetrahedra, and faces with four equivalent SLa4Sm6 tetrahedra. In the second S2- site, S2- is bonded to six equivalent Sm2+ and four equivalent La2+ atoms to form distorted SLa4Sm6 tetrahedra that share corners with four equivalent SmLa4S10 tetrahedra, corners with twelve equivalent LaSm4S4 tetrahedra, corners with eighteen SSm4 tetrahedra, edges with six equivalent SmLa4S10 tetrahedra, faces with four equivalent LaSm4S4 tetrahedra, and faces with sixteen SLa4Sm6 tetrahedra.

36 MATERIALS SCIENCE↗

Materials Data on LaSmS2 by Materials Project

SmLaS2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Sm2+ is bonded to six equivalent S2- atoms to form SmS6 octahedra that share corners with six equivalent LaS6 octahedra, edges with six equivalent SmS6 octahedra, and edges with six equivalent LaS6 octahedra. The corner-sharing octahedral tilt angles are 2°. All Sm–S bond lengths are 2.85 Å. La2+ is bonded to six equivalent S2- atoms to form LaS6 octahedra that share corners with six equivalent SmS6 octahedra, edges with six equivalent SmS6 octahedra, and edges with six equivalent LaS6 octahedra. The corner-sharing octahedral tilt angles are 2°. All La–S bond lengths are 2.93 Å. S2- is bonded to three equivalent Sm2+ and three equivalent La2+ atoms to form a mixture of corner and edge-sharing SLa3Sm3 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗