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DOE OSTI2020

Materials Data on CsRe6Se8I3 by Materials Project

CsRe6Se8I3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Cs1+ is bonded in a 9-coordinate geometry to four Se2- and five I1- atoms. There are a spread of Cs–Se bond distances ranging from 4.04–4.17 Å. There are a spread of Cs–I bond distances ranging from 3.99–4.25 Å. There are six inequivalent Re3+ sites. In the first Re3+ site, Re3+ is bonded to five Se2- atoms to form a mixture of edge and corner-sharing ReSe5 square pyramids. There are a spread of Re–Se bond distances ranging from 2.54–2.65 Å. In the second Re3+ site, Re3+ is bonded to four Se2- and one I1- atom to form a mixture of edge and corner-sharing ReSe4I square pyramids. There are one shorter (2.53 Å) and three longer (2.55 Å) Re–Se bond lengths. The Re–I bond length is 2.79 Å. In the third Re3+ site, Re3+ is bonded to five Se2- atoms to form ReSe5 square pyramids that share corners with two ReSe4I square pyramids and edges with five ReSe5 square pyramids. There are a spread of Re–Se bond distances ranging from 2.54–2.65 Å. In the fourth Re3+ site, Re3+ is bonded to four Se2- and one I1- atom to form a mixture of edge and corner-sharing ReSe4I square pyramids. There are three shorter (2.54 Å) and one longer (2.55 Å) Re–Se bond lengths. The Re–I bond length is 2.88 Å. In the fifth Re3+ site, Re3+ is bonded to four Se2- and one I1- atom to form a mixture of edge and corner-sharing ReSe4I square pyramids. There are one shorter (2.53 Å) and three longer (2.55 Å) Re–Se bond lengths. The Re–I bond length is 2.79 Å. In the sixth Re3+ site, Re3+ is bonded to four Se2- and one I1- atom to form a mixture of edge and corner-sharing ReSe4I square pyramids. There are three shorter (2.54 Å) and one longer (2.55 Å) Re–Se bond lengths. The Re–I bond length is 2.87 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to one Cs1+ and three Re3+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to three Re3+ atoms. In the third Se2- site, Se2- is bonded in a 4-coordinate geometry to three Re3+ atoms. In the fourth Se2- site, Se2- is bonded in a 4-coordinate geometry to one Cs1+ and three Re3+ atoms. In the fifth Se2- site, Se2- is bonded in a 4-coordinate geometry to four Re3+ atoms. In the sixth Se2- site, Se2- is bonded in a 4-coordinate geometry to one Cs1+ and three Re3+ atoms. In the seventh Se2- site, Se2- is bonded in a 4-coordinate geometry to one Cs1+ and three Re3+ atoms. In the eighth Se2- site, Se2- is bonded in a 4-coordinate geometry to four Re3+ atoms. There are three inequivalent I1- sites. In the first I1- site, I1- is bonded in a 1-coordinate geometry to two equivalent Cs1+ and one Re3+ atom. In the second I1- site, I1- is bonded in a distorted bent 120 degrees geometry to one Cs1+ and two Re3+ atoms. In the third I1- site, I1- is bonded in a 1-coordinate geometry to two equivalent Cs1+ and one Re3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Bi8Se7 by Materials Project

Bi4Se3(BiSe)4 is Calaverite-like structured and crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of three Bi4Se3 sheets oriented in the (0, 0, 1) direction and four BiSe sheets oriented in the (0, 0, 1) direction. In each Bi4Se3 sheet, there are four inequivalent Bi+1.75+ sites. In the first Bi+1.75+ site, Bi+1.75+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.91 Å) and three longer (3.12 Å) Bi–Se bond lengths. In the second Bi+1.75+ site, Bi+1.75+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.92 Å) and three longer (3.11 Å) Bi–Se bond lengths. In the third Bi+1.75+ site, Bi+1.75+ is bonded in a 3-coordinate geometry to three equivalent Se2- atoms. All Bi–Se bond lengths are 3.64 Å. In the fourth Bi+1.75+ site, Bi+1.75+ is bonded in a 3-coordinate geometry to three equivalent Se2- atoms. All Bi–Se bond lengths are 3.61 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to six Bi+1.75+ atoms. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to six Bi+1.75+ atoms. In the third Se2- site, Se2- is bonded to six Bi+1.75+ atoms to form edge-sharing SeBi6 octahedra. In each BiSe sheet, there are three inequivalent Bi+1.75+ sites. In the first Bi+1.75+ site, Bi+1.75+ is bonded in a 3-coordinate geometry to three equivalent Se2- atoms. All Bi–Se bond lengths are 3.60 Å. In the second Bi+1.75+ site, Bi+1.75+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are three shorter (2.89 Å) and three longer (3.13 Å) Bi–Se bond lengths. In the third Bi+1.75+ site, Bi+1.75+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are three shorter (2.92 Å) and three longer (3.09 Å) Bi–Se bond lengths. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to six Bi+1.75+ atoms to form edge-sharing SeBi6 octahedra. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to six Bi+1.75+ atoms. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Bi+1.75+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2In3AgSe6 by Materials Project

K2AgIn3Se6 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of K–Se bond distances ranging from 3.38–3.97 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven Se2- atoms. There are a spread of K–Se bond distances ranging from 3.39–3.97 Å. Ag1+ is bonded to four Se2- atoms to form AgSe4 tetrahedra that share corners with eight InSe4 tetrahedra. There are two shorter (2.64 Å) and two longer (2.68 Å) Ag–Se bond lengths. There are four inequivalent In3+ sites. In the first In3+ site, In3+ is bonded to four Se2- atoms to form InSe4 tetrahedra that share corners with two equivalent AgSe4 tetrahedra and corners with four InSe4 tetrahedra. There are a spread of In–Se bond distances ranging from 2.62–2.64 Å. In the second In3+ site, In3+ is bonded to four Se2- atoms to form InSe4 tetrahedra that share corners with four equivalent AgSe4 tetrahedra and corners with four InSe4 tetrahedra. There are two shorter (2.62 Å) and two longer (2.65 Å) In–Se bond lengths. In the third In3+ site, In3+ is bonded to four Se2- atoms to form InSe4 tetrahedra that share corners with four equivalent AgSe4 tetrahedra and corners with four InSe4 tetrahedra. There are two shorter (2.62 Å) and two longer (2.65 Å) In–Se bond lengths. In the fourth In3+ site, In3+ is bonded to four Se2- atoms to form InSe4 tetrahedra that share corners with two equivalent AgSe4 tetrahedra and corners with four InSe4 tetrahedra. All In–Se bond lengths are 2.63 Å. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to two K1+, one Ag1+, and two In3+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to two K1+, one Ag1+, and two In3+ atoms. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to two K1+, one Ag1+, and two In3+ atoms. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to two K1+, one Ag1+, and two In3+ atoms. In the fifth Se2- site, Se2- is bonded in a 4-coordinate geometry to three K1+ and two In3+ atoms. In the sixth Se2- site, Se2- is bonded in a 4-coordinate geometry to three K1+ and two In3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on C7SeNF5 by Materials Project

C4NSeF2(CF)3 crystallizes in the monoclinic P2_1/c space group. The structure is one-dimensional and consists of twenty-four fluoromethane molecules and six C4NSeF2 ribbons oriented in the (0, 1, 0) direction. In two of the C4NSeF2 ribbons, there are four inequivalent C+1.43+ sites. In the first C+1.43+ site, C+1.43+ is bonded in a 3-coordinate geometry to two C+1.43+ and one Se2- atom. Both C–C bond lengths are 1.40 Å. The C–Se bond length is 1.93 Å. In the second C+1.43+ site, C+1.43+ is bonded in a distorted single-bond geometry to one N3- and one Se2- atom. The C–N bond length is 1.17 Å. The C–Se bond length is 1.86 Å. In the third C+1.43+ site, C+1.43+ is bonded in a single-bond geometry to one C+1.43+ and one F1- atom. The C–F bond length is 1.35 Å. In the fourth C+1.43+ site, C+1.43+ is bonded in a single-bond geometry to one C+1.43+ and one F1- atom. The C–F bond length is 1.35 Å. N3- is bonded in a single-bond geometry to one C+1.43+ and two equivalent Se2- atoms. There are one shorter (2.93 Å) and one longer (3.47 Å) N–Se bond lengths. Se2- is bonded in a 3-coordinate geometry to two C+1.43+, two equivalent N3-, and two F1- atoms. There are one shorter (3.11 Å) and one longer (3.12 Å) Se–F bond lengths. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one C+1.43+ and one Se2- atom. In the second F1- site, F1- is bonded in a single-bond geometry to one C+1.43+ and one Se2- atom. In four of the C4NSeF2 ribbons, there are four inequivalent C+1.43+ sites. In the first C+1.43+ site, C+1.43+ is bonded in a single-bond geometry to one C+1.43+ and one F1- atom. The C–C bond length is 1.40 Å. The C–F bond length is 1.35 Å. In the second C+1.43+ site, C+1.43+ is bonded in a 3-coordinate geometry to two C+1.43+ and one Se2- atom. The C–C bond length is 1.40 Å. The C–Se bond length is 1.93 Å. In the third C+1.43+ site, C+1.43+ is bonded in a distorted single-bond geometry to one N3- and one Se2- atom. The C–N bond length is 1.17 Å. The C–Se bond length is 1.86 Å. In the fourth C+1.43+ site, C+1.43+ is bonded in a single-bond geometry to one C+1.43+ and one F1- atom. The C–F bond length is 1.35 Å. N3- is bonded in a single-bond geometry to one C+1.43+ and one Se2- atom. The N–Se bond length is 2.94 Å. Se2- is bonded in a 3-coordinate geometry to two C+1.43+ and one N3- atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one C+1.43+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one C+1.43+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb2Se3 by Materials Project

Yb2Se3 crystallizes in the tetragonal I-42d space group. The structure is three-dimensional. there are three inequivalent Yb3+ sites. In the first Yb3+ site, Yb3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Yb–Se bond distances ranging from 2.92–3.41 Å. In the second Yb3+ site, Yb3+ is bonded to eight Se2- atoms to form distorted edge-sharing YbSe8 hexagonal bipyramids. There are a spread of Yb–Se bond distances ranging from 2.99–3.14 Å. In the third Yb3+ site, Yb3+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Yb–Se bond distances ranging from 2.94–3.42 Å. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to six Yb3+ atoms to form a mixture of distorted face, edge, and corner-sharing SeYb6 octahedra. The corner-sharing octahedra tilt angles range from 25–43°. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to five Yb3+ and one Se2- atom. The Se–Se bond length is 2.45 Å. In the third Se2- site, Se2- is bonded in a 6-coordinate geometry to five Yb3+ and one Se2- atom. The Se–Se bond length is 2.42 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Fe(Mo3Se4)2 by Materials Project

Fe(Mo3Se4)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are six inequivalent Mo+2.17+ sites. In the first Mo+2.17+ site, Mo+2.17+ is bonded to five Se2- atoms to form a mixture of corner and edge-sharing MoSe5 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.56–2.75 Å. In the second Mo+2.17+ site, Mo+2.17+ is bonded to five Se2- atoms to form a mixture of corner and edge-sharing MoSe5 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.56–2.66 Å. In the third Mo+2.17+ site, Mo+2.17+ is bonded to five Se2- atoms to form a mixture of corner and edge-sharing MoSe5 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.56–2.73 Å. In the fourth Mo+2.17+ site, Mo+2.17+ is bonded to five Se2- atoms to form a mixture of corner and edge-sharing MoSe5 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.59–2.71 Å. In the fifth Mo+2.17+ site, Mo+2.17+ is bonded to five Se2- atoms to form a mixture of corner and edge-sharing MoSe5 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.58–2.74 Å. In the sixth Mo+2.17+ site, Mo+2.17+ is bonded to five Se2- atoms to form a mixture of corner and edge-sharing MoSe5 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.55–2.74 Å. Fe3+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Fe–Se bond distances ranging from 2.41–2.57 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to three Mo+2.17+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to four Mo+2.17+ and one Fe3+ atom. In the third Se2- site, Se2- is bonded in a 4-coordinate geometry to four Mo+2.17+ atoms. In the fourth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to four Mo+2.17+ atoms. In the fifth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to four Mo+2.17+ atoms. In the sixth Se2- site, Se2- is bonded in a 1-coordinate geometry to four Mo+2.17+ and one Fe3+ atom. In the seventh Se2- site, Se2- is bonded in a 1-coordinate geometry to three Mo+2.17+ and one Fe3+ atom. In the eighth Se2- site, Se2- is bonded in a 5-coordinate geometry to four Mo+2.17+ and one Fe3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li10Ge(PSe6)2 by Materials Project

Li10Ge(PSe6)2 crystallizes in the tetragonal P4_2mc space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Li–Se bond distances ranging from 2.54–2.89 Å. In the second Li1+ site, Li1+ is bonded to six Se2- atoms to form LiSe6 octahedra that share corners with two equivalent PSe4 tetrahedra, edges with two equivalent PSe4 tetrahedra, and edges with four equivalent LiSe5 trigonal bipyramids. There are a spread of Li–Se bond distances ranging from 2.76–2.84 Å. In the third Li1+ site, Li1+ is bonded to six Se2- atoms to form LiSe6 octahedra that share corners with two equivalent PSe4 tetrahedra, edges with two equivalent GeSe4 tetrahedra, and faces with four equivalent LiSe5 trigonal bipyramids. There are a spread of Li–Se bond distances ranging from 2.77–2.93 Å. In the fourth Li1+ site, Li1+ is bonded to five Se2- atoms to form distorted LiSe5 trigonal bipyramids that share a cornercorner with one PSe4 tetrahedra, corners with two equivalent GeSe4 tetrahedra, corners with three equivalent LiSe5 trigonal bipyramids, an edgeedge with one LiSe6 octahedra, an edgeedge with one PSe4 tetrahedra, an edgeedge with one LiSe5 trigonal bipyramid, and a faceface with one LiSe6 octahedra. There are a spread of Li–Se bond distances ranging from 2.52–3.08 Å. Ge4+ is bonded to four Se2- atoms to form GeSe4 tetrahedra that share corners with eight equivalent LiSe5 trigonal bipyramids and edges with two equivalent LiSe6 octahedra. There are two shorter (2.39 Å) and two longer (2.41 Å) Ge–Se bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four Se2- atoms to form PSe4 tetrahedra that share corners with four equivalent LiSe5 trigonal bipyramids and edges with two equivalent LiSe6 octahedra. There are two shorter (2.22 Å) and two longer (2.25 Å) P–Se bond lengths. In the second P5+ site, P5+ is bonded to four Se2- atoms to form PSe4 tetrahedra that share corners with four LiSe6 octahedra and edges with four equivalent LiSe5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 43–50°. There are two shorter (2.22 Å) and two longer (2.24 Å) P–Se bond lengths. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three Li1+ and one P5+ atom to form a mixture of edge and corner-sharing SeLi3P trigonal pyramids. In the second Se2- site, Se2- is bonded in a distorted hexagonal planar geometry to five Li1+ and one Ge4+ atom. In the third Se2- site, Se2- is bonded in a rectangular see-saw-like geometry to three Li1+ and one P5+ atom. In the fourth Se2- site, Se2- is bonded in a 6-coordinate geometry to five Li1+ and one Ge4+ atom. In the fifth Se2- site, Se2- is bonded in a 6-coordinate geometry to five Li1+ and one P5+ atom. In the sixth Se2- site, Se2- is bonded to three Li1+ and one P5+ atom to form distorted corner-sharing SeLi3P trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TlPd2Se3 by Materials Project

Pd2TlSe3 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. there are two inequivalent Pd2+ sites. In the first Pd2+ site, Pd2+ is bonded to six equivalent Se+1.67- atoms to form edge-sharing PdSe6 octahedra. All Pd–Se bond lengths are 2.55 Å. In the second Pd2+ site, Pd2+ is bonded to two equivalent Tl1+ and four equivalent Se+1.67- atoms to form edge-sharing PdTl2Se4 octahedra. Both Pd–Tl bond lengths are 3.06 Å. All Pd–Se bond lengths are 2.50 Å. Tl1+ is bonded in a 6-coordinate geometry to three equivalent Pd2+ and three equivalent Se+1.67- atoms. All Tl–Se bond lengths are 3.38 Å. Se+1.67- is bonded in a 4-coordinate geometry to three Pd2+ and one Tl1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li10Sn(PSe6)2 by Materials Project

Li10Sn(PSe6)2 crystallizes in the tetragonal P4_2mc space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Li–Se bond distances ranging from 2.57–2.97 Å. In the second Li1+ site, Li1+ is bonded to six Se2- atoms to form LiSe6 octahedra that share corners with two equivalent PSe4 tetrahedra, edges with two equivalent PSe4 tetrahedra, and edges with four equivalent LiSe5 trigonal bipyramids. There are a spread of Li–Se bond distances ranging from 2.76–2.86 Å. In the third Li1+ site, Li1+ is bonded to six Se2- atoms to form LiSe6 octahedra that share corners with two equivalent PSe4 tetrahedra, edges with two equivalent SnSe4 tetrahedra, and faces with four equivalent LiSe5 trigonal bipyramids. There are a spread of Li–Se bond distances ranging from 2.83–2.94 Å. In the fourth Li1+ site, Li1+ is bonded to five Se2- atoms to form distorted LiSe5 trigonal bipyramids that share a cornercorner with one PSe4 tetrahedra, corners with two equivalent SnSe4 tetrahedra, corners with three equivalent LiSe5 trigonal bipyramids, an edgeedge with one LiSe6 octahedra, an edgeedge with one PSe4 tetrahedra, an edgeedge with one LiSe5 trigonal bipyramid, and a faceface with one LiSe6 octahedra. There are a spread of Li–Se bond distances ranging from 2.53–3.10 Å. Sn4+ is bonded to four Se2- atoms to form SnSe4 tetrahedra that share corners with eight equivalent LiSe5 trigonal bipyramids and edges with two equivalent LiSe6 octahedra. There are two shorter (2.55 Å) and two longer (2.56 Å) Sn–Se bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four Se2- atoms to form PSe4 tetrahedra that share corners with four equivalent LiSe5 trigonal bipyramids and edges with two equivalent LiSe6 octahedra. There are two shorter (2.22 Å) and two longer (2.24 Å) P–Se bond lengths. In the second P5+ site, P5+ is bonded to four Se2- atoms to form PSe4 tetrahedra that share corners with four LiSe6 octahedra and edges with four equivalent LiSe5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 43–50°. There are two shorter (2.22 Å) and two longer (2.24 Å) P–Se bond lengths. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three Li1+ and one P5+ atom to form a mixture of edge and corner-sharing SeLi3P trigonal pyramids. In the second Se2- site, Se2- is bonded in a distorted hexagonal planar geometry to five Li1+ and one Sn4+ atom. In the third Se2- site, Se2- is bonded in a rectangular see-saw-like geometry to three Li1+ and one P5+ atom. In the fourth Se2- site, Se2- is bonded in a 6-coordinate geometry to five Li1+ and one Sn4+ atom. In the fifth Se2- site, Se2- is bonded in a 6-coordinate geometry to five Li1+ and one P5+ atom. In the sixth Se2- site, Se2- is bonded to three Li1+ and one P5+ atom to form distorted corner-sharing SeLi3P trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li10Si(PSe6)2 by Materials Project

Li10Si(PSe6)2 crystallizes in the tetragonal P4_2mc space group. The structure is three-dimensional. there are four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Li–Se bond distances ranging from 2.52–2.85 Å. In the second Li1+ site, Li1+ is bonded to six Se2- atoms to form LiSe6 octahedra that share corners with two equivalent PSe4 tetrahedra, edges with two equivalent PSe4 tetrahedra, and edges with four equivalent LiSe5 trigonal bipyramids. There are a spread of Li–Se bond distances ranging from 2.76–2.83 Å. In the third Li1+ site, Li1+ is bonded to six Se2- atoms to form LiSe6 octahedra that share corners with two equivalent PSe4 tetrahedra, edges with two equivalent SiSe4 tetrahedra, and faces with four equivalent LiSe5 trigonal bipyramids. There are a spread of Li–Se bond distances ranging from 2.73–2.93 Å. In the fourth Li1+ site, Li1+ is bonded to five Se2- atoms to form distorted LiSe5 trigonal bipyramids that share a cornercorner with one PSe4 tetrahedra, corners with two equivalent SiSe4 tetrahedra, corners with three equivalent LiSe5 trigonal bipyramids, an edgeedge with one LiSe6 octahedra, an edgeedge with one PSe4 tetrahedra, an edgeedge with one LiSe5 trigonal bipyramid, and a faceface with one LiSe6 octahedra. There are a spread of Li–Se bond distances ranging from 2.51–3.07 Å. Si4+ is bonded to four Se2- atoms to form SiSe4 tetrahedra that share corners with eight equivalent LiSe5 trigonal bipyramids and edges with two equivalent LiSe6 octahedra. There are two shorter (2.30 Å) and two longer (2.32 Å) Si–Se bond lengths. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four Se2- atoms to form PSe4 tetrahedra that share corners with four equivalent LiSe5 trigonal bipyramids and edges with two equivalent LiSe6 octahedra. There are two shorter (2.21 Å) and two longer (2.25 Å) P–Se bond lengths. In the second P5+ site, P5+ is bonded to four Se2- atoms to form PSe4 tetrahedra that share corners with four LiSe6 octahedra and edges with four equivalent LiSe5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 43–50°. There are two shorter (2.22 Å) and two longer (2.24 Å) P–Se bond lengths. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three Li1+ and one P5+ atom to form edge-sharing SeLi3P trigonal pyramids. In the second Se2- site, Se2- is bonded in a distorted hexagonal planar geometry to five Li1+ and one Si4+ atom. In the third Se2- site, Se2- is bonded in a rectangular see-saw-like geometry to three Li1+ and one P5+ atom. In the fourth Se2- site, Se2- is bonded in a 6-coordinate geometry to five Li1+ and one Si4+ atom. In the fifth Se2- site, Se2- is bonded in a 6-coordinate geometry to five Li1+ and one P5+ atom. In the sixth Se2- site, Se2- is bonded in a 4-coordinate geometry to three Li1+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnCu4(SnSe4)2 by Materials Project

Cu4Zn(SnSe4)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Cu+1.50+ sites. In the first Cu+1.50+ site, Cu+1.50+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with three equivalent ZnSe4 tetrahedra, corners with four CuSe4 tetrahedra, and corners with four SnSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.39–2.45 Å. In the second Cu+1.50+ site, Cu+1.50+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share a cornercorner with one ZnSe4 tetrahedra, corners with four CuSe4 tetrahedra, and corners with four SnSe4 tetrahedra. There are three shorter (2.40 Å) and one longer (2.47 Å) Cu–Se bond lengths. In the third Cu+1.50+ site, Cu+1.50+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share a cornercorner with one ZnSe4 tetrahedra, corners with four CuSe4 tetrahedra, and corners with four SnSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.40–2.44 Å. In the fourth Cu+1.50+ site, Cu+1.50+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with three equivalent ZnSe4 tetrahedra, corners with four CuSe4 tetrahedra, and corners with four SnSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.39–2.43 Å. Zn2+ is bonded to four Se2- atoms to form ZnSe4 tetrahedra that share corners with four SnSe4 tetrahedra and corners with eight CuSe4 tetrahedra. There are a spread of Zn–Se bond distances ranging from 2.47–2.49 Å. There are two inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded to four Se2- atoms to form SnSe4 tetrahedra that share corners with two equivalent ZnSe4 tetrahedra and corners with eight CuSe4 tetrahedra. There are two shorter (2.58 Å) and two longer (2.63 Å) Sn–Se bond lengths. In the second Sn4+ site, Sn4+ is bonded to four Se2- atoms to form SnSe4 tetrahedra that share corners with two equivalent ZnSe4 tetrahedra and corners with eight CuSe4 tetrahedra. There are a spread of Sn–Se bond distances ranging from 2.57–2.64 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to two Cu+1.50+, one Zn2+, and one Sn4+ atom to form corner-sharing SeZnCu2Sn tetrahedra. In the second Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to two Cu+1.50+ and one Sn4+ atom. In the third Se2- site, Se2- is bonded to two Cu+1.50+, one Zn2+, and one Sn4+ atom to form corner-sharing SeZnCu2Sn tetrahedra. In the fourth Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to two Cu+1.50+ and one Sn4+ atom. In the fifth Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to two Cu+1.50+ and one Sn4+ atom. In the sixth Se2- site, Se2- is bonded to two Cu+1.50+, one Zn2+, and one Sn4+ atom to form corner-sharing SeZnCu2Sn tetrahedra. In the seventh Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to two Cu+1.50+ and one Sn4+ atom. In the eighth Se2- site, Se2- is bonded to two Cu+1.50+, one Zn2+, and one Sn4+ atom to form corner-sharing SeZnCu2Sn tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LuSe2 by Materials Project

LuSe2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Lu3+ is bonded in a 9-coordinate geometry to nine Se+1.50- atoms. There are a spread of Lu–Se bond distances ranging from 2.90–3.02 Å. There are two inequivalent Se+1.50- sites. In the first Se+1.50- site, Se+1.50- is bonded to five equivalent Lu3+ atoms to form a mixture of distorted edge and corner-sharing SeLu5 trigonal bipyramids. In the second Se+1.50- site, Se+1.50- is bonded in a 8-coordinate geometry to four equivalent Lu3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaSe2 by Materials Project

LaSe2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. La3+ is bonded in a 9-coordinate geometry to nine Se+1.50- atoms. There are a spread of La–Se bond distances ranging from 3.09–3.20 Å. There are two inequivalent Se+1.50- sites. In the first Se+1.50- site, Se+1.50- is bonded to five equivalent La3+ atoms to form a mixture of distorted corner and edge-sharing SeLa5 trigonal bipyramids. In the second Se+1.50- site, Se+1.50- is bonded in a 8-coordinate geometry to four equivalent La3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na4Zn3Se5 by Materials Project

Na4Zn3Se5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to five Se2- atoms to form distorted NaSe5 trigonal bipyramids that share corners with two equivalent NaSe6 octahedra, corners with two equivalent NaSe5 square pyramids, corners with three ZnSe4 tetrahedra, corners with four equivalent NaSe5 trigonal bipyramids, an edgeedge with one NaSe6 octahedra, edges with four ZnSe4 tetrahedra, and edges with four NaSe5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 33°. There are a spread of Na–Se bond distances ranging from 2.83–2.94 Å. In the second Na1+ site, Na1+ is bonded to five Se2- atoms to form NaSe5 square pyramids that share corners with three equivalent NaSe6 octahedra, corners with four ZnSe4 tetrahedra, corners with five NaSe5 trigonal bipyramids, edges with four equivalent NaSe5 square pyramids, and edges with four ZnSe4 tetrahedra. The corner-sharing octahedra tilt angles range from 34–54°. There are three shorter (3.08 Å) and two longer (3.13 Å) Na–Se bond lengths. In the third Na1+ site, Na1+ is bonded to six Se2- atoms to form NaSe6 octahedra that share corners with three equivalent NaSe5 square pyramids, corners with five ZnSe4 tetrahedra, corners with four NaSe5 trigonal bipyramids, edges with four equivalent NaSe6 octahedra, edges with five ZnSe4 tetrahedra, an edgeedge with one NaSe5 trigonal bipyramid, and a faceface with one NaSe5 trigonal bipyramid. There are a spread of Na–Se bond distances ranging from 2.99–3.25 Å. In the fourth Na1+ site, Na1+ is bonded to five Se2- atoms to form distorted NaSe5 trigonal bipyramids that share corners with two equivalent NaSe6 octahedra, corners with three equivalent NaSe5 square pyramids, corners with six ZnSe4 tetrahedra, corners with four equivalent NaSe5 trigonal bipyramids, edges with two equivalent ZnSe4 tetrahedra, edges with four NaSe5 trigonal bipyramids, and a faceface with one NaSe6 octahedra. The corner-sharing octahedral tilt angles are 60°. There are a spread of Na–Se bond distances ranging from 2.89–3.07 Å. There are three inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to four Se2- atoms to form ZnSe4 tetrahedra that share a cornercorner with one NaSe6 octahedra, corners with two equivalent NaSe5 square pyramids, corners with six ZnSe4 tetrahedra, corners with three NaSe5 trigonal bipyramids, edges with two equivalent NaSe6 octahedra, and edges with three equivalent NaSe5 square pyramids. The corner-sharing octahedral tilt angles are 15°. There are two shorter (2.52 Å) and two longer (2.53 Å) Zn–Se bond lengths. In the second Zn2+ site, Zn2+ is bonded to four Se2- atoms to form ZnSe4 tetrahedra that share corners with two equivalent NaSe6 octahedra, corners with two equivalent NaSe5 square pyramids, corners with six ZnSe4 tetrahedra, corners with two equivalent NaSe5 trigonal bipyramids, an edgeedge with one NaSe5 square pyramid, and edges with four NaSe5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 48°. There are a spread of Zn–Se bond distances ranging from 2.45–2.61 Å. In the third Zn2+ site, Zn2+ is bonded to four Se2- atoms to form ZnSe4 tetrahedra that share corners with two equivalent NaSe6 octahedra, corners with six ZnSe4 tetrahedra, corners with four equivalent NaSe5 trigonal bipyramids, edges with three equivalent NaSe6 octahedra, and edges with two equivalent NaSe5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 18°. There are a spread of Zn–Se bond distances ranging from 2.48–2.60 Å. There are five inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to four Na1+ and two Zn2+ atoms. In the second Se2- site, Se2- is bonded in a 7-coordinate geometry to five Na1+ and two equivalent Zn2+ atoms. In the third Se2- site, Se2- is bonded in a 8-coordinate geometry to six Na1+ and two Zn2+ atoms. In the fourth Se2- site, Se2- is bonded to three equivalent Na1+ and three Zn2+ atoms to form a mixture of distorted edge and corner-sharing SeNa3Zn3 octahedra. The corner-sharing octahedral tilt angles are 73°. In the fifth Se2- site, Se2- is bonded to three Na1+ and three Zn2+ atoms to form a mixture of distorted edge and corner-sharing SeNa3Zn3 octahedra. The corner-sharing octahedral tilt angles are 73°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsBi4Se7 by Materials Project

CsBi4Se7 is Orthorhombic Perovskite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Cs1+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.64–3.92 Å. There are four inequivalent Bi+3.25+ sites. In the first Bi+3.25+ site, Bi+3.25+ is bonded to six Se2- atoms to form a mixture of corner and edge-sharing BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 5–6°. There are a spread of Bi–Se bond distances ranging from 2.92–3.01 Å. In the second Bi+3.25+ site, Bi+3.25+ is bonded to six Se2- atoms to form a mixture of corner and edge-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are a spread of Bi–Se bond distances ranging from 2.77–3.16 Å. In the third Bi+3.25+ site, Bi+3.25+ is bonded to six Se2- atoms to form a mixture of corner and edge-sharing BiSe6 octahedra. The corner-sharing octahedra tilt angles range from 3–6°. There are a spread of Bi–Se bond distances ranging from 2.80–3.17 Å. In the fourth Bi+3.25+ site, Bi+3.25+ is bonded to six Se2- atoms to form a mixture of corner and edge-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 5°. There are a spread of Bi–Se bond distances ranging from 2.75–3.32 Å. There are seven inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to two equivalent Bi+3.25+ and one Se2- atom. The Se–Se bond length is 2.37 Å. In the second Se2- site, Se2- is bonded to two equivalent Cs1+ and three Bi+3.25+ atoms to form distorted SeCs2Bi3 square pyramids that share a cornercorner with one SeBi6 octahedra, corners with six SeCs2Bi3 trigonal bipyramids, edges with two equivalent SeBi6 octahedra, edges with two equivalent SeCs2Bi3 square pyramids, and edges with two SeCs2Bi3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 7°. In the third Se2- site, Se2- is bonded in a distorted T-shaped geometry to three Bi+3.25+ atoms. In the fourth Se2- site, Se2- is bonded to six Bi+3.25+ atoms to form SeBi6 octahedra that share a cornercorner with one SeCs2Bi3 square pyramid, edges with four equivalent SeBi6 octahedra, edges with two equivalent SeCs2Bi3 square pyramids, and edges with two equivalent SeCsBi4 trigonal bipyramids. In the fifth Se2- site, Se2- is bonded in a distorted see-saw-like geometry to one Cs1+ and three Bi+3.25+ atoms. In the sixth Se2- site, Se2- is bonded to two equivalent Cs1+ and three equivalent Bi+3.25+ atoms to form distorted SeCs2Bi3 trigonal bipyramids that share corners with two equivalent SeCs2Bi3 square pyramids, a cornercorner with one SeCsBi4 trigonal bipyramid, an edgeedge with one SeCs2Bi3 square pyramid, and edges with six SeCs2Bi3 trigonal bipyramids. In the seventh Se2- site, Se2- is bonded to one Cs1+ and four Bi+3.25+ atoms to form distorted SeCsBi4 trigonal bipyramids that share corners with four equivalent SeCs2Bi3 square pyramids, corners with three SeCs2Bi3 trigonal bipyramids, edges with two equivalent SeBi6 octahedra, an edgeedge with one SeCs2Bi3 square pyramid, and edges with two equivalent SeCs2Bi3 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LaMo6(SeS)4 by Materials Project

LaMo6(SeS)4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. La3+ is bonded in a body-centered cubic geometry to four Se2- and four S2- atoms. There are a spread of La–Se bond distances ranging from 3.08–3.20 Å. There are a spread of La–S bond distances ranging from 2.85–3.18 Å. There are six inequivalent Mo+2.17+ sites. In the first Mo+2.17+ site, Mo+2.17+ is bonded to three Se2- and two S2- atoms to form a mixture of edge and corner-sharing MoSe3S2 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.56–2.70 Å. There are one shorter (2.41 Å) and one longer (2.53 Å) Mo–S bond lengths. In the second Mo+2.17+ site, Mo+2.17+ is bonded to three Se2- and two S2- atoms to form a mixture of edge and corner-sharing MoSe3S2 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.57–2.72 Å. There are one shorter (2.42 Å) and one longer (2.47 Å) Mo–S bond lengths. In the third Mo+2.17+ site, Mo+2.17+ is bonded to two Se2- and three S2- atoms to form a mixture of edge and corner-sharing MoSe2S3 square pyramids. There are one shorter (2.58 Å) and one longer (2.69 Å) Mo–Se bond lengths. There are a spread of Mo–S bond distances ranging from 2.42–2.54 Å. In the fourth Mo+2.17+ site, Mo+2.17+ is bonded to two Se2- and three S2- atoms to form a mixture of edge and corner-sharing MoSe2S3 square pyramids. There are one shorter (2.60 Å) and one longer (2.68 Å) Mo–Se bond lengths. There are a spread of Mo–S bond distances ranging from 2.42–2.68 Å. In the fifth Mo+2.17+ site, Mo+2.17+ is bonded to three Se2- and two S2- atoms to form a mixture of edge and corner-sharing MoSe3S2 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.60–2.74 Å. There are one shorter (2.42 Å) and one longer (2.48 Å) Mo–S bond lengths. In the sixth Mo+2.17+ site, Mo+2.17+ is bonded to three Se2- and two S2- atoms to form a mixture of edge and corner-sharing MoSe3S2 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.58–2.69 Å. There are one shorter (2.41 Å) and one longer (2.67 Å) Mo–S bond lengths. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to one La3+ and four Mo+2.17+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to one La3+ and four Mo+2.17+ atoms. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to one La3+ and four Mo+2.17+ atoms. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to one La3+ and four Mo+2.17+ atoms. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to one La3+ and three Mo+2.17+ atoms. In the second S2- site, S2- is bonded in a 4-coordinate geometry to one La3+ and three Mo+2.17+ atoms. In the third S2- site, S2- is bonded in a 5-coordinate geometry to one La3+ and four Mo+2.17+ atoms. In the fourth S2- site, S2- is bonded in a 5-coordinate geometry to one La3+ and four Mo+2.17+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K(Ti3Se4)4 by Materials Project

K(Ti3Se4)4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. K1+ is bonded in a distorted hexagonal planar geometry to six Se2- atoms. All K–Se bond lengths are 3.41 Å. There are six inequivalent Ti+2.58+ sites. In the first Ti+2.58+ site, Ti+2.58+ is bonded to six Se2- atoms to form a mixture of face, edge, and corner-sharing TiSe6 octahedra. The corner-sharing octahedra tilt angles range from 42–51°. There are a spread of Ti–Se bond distances ranging from 2.57–2.67 Å. In the second Ti+2.58+ site, Ti+2.58+ is bonded to six Se2- atoms to form a mixture of face, edge, and corner-sharing TiSe6 octahedra. The corner-sharing octahedra tilt angles range from 43–51°. There are a spread of Ti–Se bond distances ranging from 2.56–2.68 Å. In the third Ti+2.58+ site, Ti+2.58+ is bonded to six Se2- atoms to form a mixture of face, edge, and corner-sharing TiSe6 octahedra. The corner-sharing octahedra tilt angles range from 42–51°. There are a spread of Ti–Se bond distances ranging from 2.56–2.67 Å. In the fourth Ti+2.58+ site, Ti+2.58+ is bonded to six Se2- atoms to form a mixture of face, edge, and corner-sharing TiSe6 octahedra. The corner-sharing octahedra tilt angles range from 42–51°. There are a spread of Ti–Se bond distances ranging from 2.56–2.67 Å. In the fifth Ti+2.58+ site, Ti+2.58+ is bonded to six Se2- atoms to form a mixture of face, edge, and corner-sharing TiSe6 octahedra. The corner-sharing octahedra tilt angles range from 42–51°. There are a spread of Ti–Se bond distances ranging from 2.56–2.66 Å. In the sixth Ti+2.58+ site, Ti+2.58+ is bonded to six Se2- atoms to form a mixture of face, edge, and corner-sharing TiSe6 octahedra. The corner-sharing octahedra tilt angles range from 42–51°. There are a spread of Ti–Se bond distances ranging from 2.56–2.67 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to one K1+ and four Ti+2.58+ atoms. In the second Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to four Ti+2.58+ atoms. In the third Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to four Ti+2.58+ atoms. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to one K1+ and four Ti+2.58+ atoms. In the fifth Se2- site, Se2- is bonded in a 5-coordinate geometry to one K1+ and four Ti+2.58+ atoms. In the sixth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to four Ti+2.58+ atoms. In the seventh Se2- site, Se2- is bonded to six Ti+2.58+ atoms to form distorted face-sharing SeTi6 pentagonal pyramids. In the eighth Se2- site, Se2- is bonded to six Ti+2.58+ atoms to form distorted face-sharing SeTi6 pentagonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on La2U2Se9 by Materials Project

U2La2Se9 crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. U6+ is bonded in a 9-coordinate geometry to nine Se2- atoms. There are a spread of U–Se bond distances ranging from 2.87–3.07 Å. There are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 10-coordinate geometry to ten Se2- atoms. There are a spread of La–Se bond distances ranging from 3.04–3.37 Å. In the second La3+ site, La3+ is bonded in a 10-coordinate geometry to eight Se2- atoms. There are a spread of La–Se bond distances ranging from 3.11–3.16 Å. There are five inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted see-saw-like geometry to two equivalent U6+ and two equivalent La3+ atoms. In the second Se2- site, Se2- is bonded to two equivalent U6+ and two La3+ atoms to form a mixture of distorted edge and corner-sharing SeLa2U2 trigonal pyramids. In the third Se2- site, Se2- is bonded in a 6-coordinate geometry to two equivalent U6+, two equivalent La3+, and two equivalent Se2- atoms. There are one shorter (2.68 Å) and one longer (2.73 Å) Se–Se bond lengths. In the fourth Se2- site, Se2- is bonded in a 6-coordinate geometry to two equivalent U6+ and two equivalent La3+ atoms. In the fifth Se2- site, Se2- is bonded in a 6-coordinate geometry to two equivalent U6+, two La3+, and two equivalent Se2- atoms. There are one shorter (2.78 Å) and one longer (2.80 Å) Se–Se bond lengths.

36 MATERIALS SCIENCE↗