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DOE OSTI2020

Materials Data on Na4Eu(SiSe3)2 by Materials Project

Na4Eu(SiSe3)2 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six Se1- atoms to form NaSe6 octahedra that share corners with two equivalent NaSe6 octahedra, corners with two equivalent EuSe6 octahedra, corners with two equivalent SiSiSe3 tetrahedra, edges with two equivalent EuSe6 octahedra, edges with eight NaSe6 octahedra, and edges with two equivalent SiSiSe3 tetrahedra. The corner-sharing octahedra tilt angles range from 7–8°. There are a spread of Na–Se bond distances ranging from 3.02–3.16 Å. In the second Na1+ site, Na1+ is bonded to six Se1- atoms to form NaSe6 octahedra that share corners with two equivalent NaSe6 octahedra, corners with two equivalent EuSe6 octahedra, corners with two equivalent SiSiSe3 tetrahedra, edges with two equivalent EuSe6 octahedra, edges with eight NaSe6 octahedra, and edges with two equivalent SiSiSe3 tetrahedra. The corner-sharing octahedra tilt angles range from 7–8°. There are a spread of Na–Se bond distances ranging from 3.01–3.16 Å. In the third Na1+ site, Na1+ is bonded to six Se1- atoms to form NaSe6 octahedra that share corners with two equivalent NaSe6 octahedra, corners with two equivalent EuSe6 octahedra, corners with two equivalent SiSiSe3 tetrahedra, edges with two equivalent EuSe6 octahedra, edges with eight NaSe6 octahedra, and edges with two equivalent SiSiSe3 tetrahedra. The corner-sharing octahedral tilt angles are 7°. There are a spread of Na–Se bond distances ranging from 3.00–3.23 Å. In the fourth Na1+ site, Na1+ is bonded to six Se1- atoms to form NaSe6 octahedra that share corners with six NaSe6 octahedra, corners with six equivalent SiSiSe3 tetrahedra, edges with three equivalent EuSe6 octahedra, and edges with six NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 7–8°. There are a spread of Na–Se bond distances ranging from 3.10–3.12 Å. Eu2+ is bonded to six Se1- atoms to form EuSe6 octahedra that share corners with six NaSe6 octahedra, corners with six equivalent SiSiSe3 tetrahedra, and edges with nine NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 7–8°. There are a spread of Eu–Se bond distances ranging from 3.09–3.11 Å. Si is bonded to one Si and three Se1- atoms to form distorted SiSiSe3 tetrahedra that share corners with three equivalent EuSe6 octahedra, corners with three SeNa4EuSi octahedra, corners with six NaSe6 octahedra, and edges with three NaSe6 octahedra. The corner-sharing octahedra tilt angles range from 20–77°. The Si–Si bond length is 2.35 Å. There are one shorter (2.30 Å) and two longer (2.31 Å) Si–Se bond lengths. There are three inequivalent Se1- sites. In the first Se1- site, Se1- is bonded to four Na1+, one Eu2+, and one Si atom to form SeNa4EuSi octahedra that share corners with seven SeNa4EuSi octahedra, a cornercorner with one SiSiSe3 tetrahedra, and edges with ten SeNa4EuSi octahedra. The corner-sharing octahedra tilt angles range from 0–91°. In the second Se1- site, Se1- is bonded to four Na1+, one Eu2+, and one Si atom to form SeNa4EuSi octahedra that share corners with seven SeNa4EuSi octahedra, a cornercorner with one SiSiSe3 tetrahedra, and edges with ten SeNa4EuSi octahedra. The corner-sharing octahedra tilt angles range from 0–91°. In the third Se1- site, Se1- is bonded to four Na1+, one Eu2+, and one Si atom to form SeNa4EuSi octahedra that share corners with seven SeNa4EuSi octahedra, a cornercorner with one SiSiSe3 tetrahedra, and edges with ten SeNa4EuSi octahedra. The corner-sharing octahedra tilt angles range from 0–91°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on RbUSeO8 by Materials Project

RbUSeO8 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Rb is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Rb–O bond distances ranging from 2.82–3.44 Å. U is bonded to seven O atoms to form distorted UO7 pentagonal bipyramids that share corners with two equivalent UO7 pentagonal bipyramids and corners with two equivalent SeO4 tetrahedra. There are a spread of U–O bond distances ranging from 1.83–2.37 Å. Se is bonded to four O atoms to form SeO4 tetrahedra that share corners with two equivalent UO7 pentagonal bipyramids. There are a spread of Se–O bond distances ranging from 1.64–1.71 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one U atom. In the second O site, O is bonded in a 1-coordinate geometry to two equivalent Rb and one Se atom. In the third O site, O is bonded in a distorted single-bond geometry to two equivalent Rb and one Se atom. In the fourth O site, O is bonded in a distorted single-bond geometry to one Rb and one U atom. In the fifth O site, O is bonded in a single-bond geometry to two equivalent Rb and one U atom. In the sixth O site, O is bonded in a bent 150 degrees geometry to two equivalent U atoms. In the seventh O site, O is bonded in a 2-coordinate geometry to two equivalent Rb, one U, and one Se atom. In the eighth O site, O is bonded in a bent 150 degrees geometry to one U and one Se atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu2SnSe3 by Materials Project

Cu2SnSe3 is Enargite-like structured and crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are four inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with five SnSe4 tetrahedra and corners with seven CuSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.41–2.44 Å. In the second Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with five SnSe4 tetrahedra and corners with seven CuSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.41–2.46 Å. In the third Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with five SnSe4 tetrahedra and corners with seven CuSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.41–2.46 Å. In the fourth Cu1+ site, Cu1+ is bonded to four Se2- atoms to form CuSe4 tetrahedra that share corners with five SnSe4 tetrahedra and corners with seven CuSe4 tetrahedra. There are a spread of Cu–Se bond distances ranging from 2.42–2.45 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 SnSe4 tetrahedra and corners with ten CuSe4 tetrahedra. There are a spread of Sn–Se bond distances ranging from 2.60–2.69 Å. In the second Sn4+ site, Sn4+ is bonded to four Se2- atoms to form SnSe4 tetrahedra that share corners with two equivalent SnSe4 tetrahedra and corners with ten CuSe4 tetrahedra. There are a spread of Sn–Se bond distances ranging from 2.60–2.70 Å. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to three Cu1+ and one Sn4+ atom to form corner-sharing SeCu3Sn tetrahedra. In the second Se2- site, Se2- is bonded to three Cu1+ and one Sn4+ atom to form corner-sharing SeCu3Sn tetrahedra. In the third Se2- site, Se2- is bonded to three Cu1+ and one Sn4+ atom to form corner-sharing SeCu3Sn tetrahedra. In the fourth Se2- site, Se2- is bonded to two Cu1+ and two Sn4+ atoms to form corner-sharing SeCu2Sn2 tetrahedra. In the fifth Se2- site, Se2- is bonded to two Cu1+ and two Sn4+ atoms to form corner-sharing SeCu2Sn2 tetrahedra. In the sixth Se2- site, Se2- is bonded to three Cu1+ and one Sn4+ atom to form corner-sharing SeCu3Sn tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ga3Cu3(Te2Se)2 by Materials Project

Cu3Ga3(Te2Se)2 is Stannite-like structured and crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are three inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to two Te2- and two Se2- atoms to form CuTe2Se2 tetrahedra that share corners with four CuTe2Se2 tetrahedra and corners with eight GaTe2Se2 tetrahedra. There are one shorter (2.58 Å) and one longer (2.59 Å) Cu–Te bond lengths. There are one shorter (2.49 Å) and one longer (2.51 Å) Cu–Se bond lengths. In the second Cu1+ site, Cu1+ is bonded to three Te2- and one Se2- atom to form CuTe3Se tetrahedra that share corners with four CuTe2Se2 tetrahedra and corners with eight GaTe2Se2 tetrahedra. There are one shorter (2.58 Å) and two longer (2.59 Å) Cu–Te bond lengths. The Cu–Se bond length is 2.45 Å. In the third Cu1+ site, Cu1+ is bonded to three Te2- and one Se2- atom to form CuTe3Se tetrahedra that share corners with four CuTe3Se tetrahedra and corners with eight GaTe3Se tetrahedra. There are a spread of Cu–Te bond distances ranging from 2.56–2.59 Å. The Cu–Se bond length is 2.45 Å. There are three inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to two Te2- and two Se2- atoms to form GaTe2Se2 tetrahedra that share corners with four GaTe2Se2 tetrahedra and corners with eight CuTe2Se2 tetrahedra. There are one shorter (2.66 Å) and one longer (2.67 Å) Ga–Te bond lengths. There are one shorter (2.51 Å) and one longer (2.53 Å) Ga–Se bond lengths. In the second Ga3+ site, Ga3+ is bonded to three Te2- and one Se2- atom to form GaTe3Se tetrahedra that share corners with four GaTe2Se2 tetrahedra and corners with eight CuTe2Se2 tetrahedra. There are one shorter (2.66 Å) and two longer (2.67 Å) Ga–Te bond lengths. The Ga–Se bond length is 2.51 Å. In the third Ga3+ site, Ga3+ is bonded to three Te2- and one Se2- atom to form GaTe3Se tetrahedra that share corners with four GaTe3Se tetrahedra and corners with eight CuTe3Se tetrahedra. There are a spread of Ga–Te bond distances ranging from 2.65–2.67 Å. The Ga–Se bond length is 2.50 Å. There are four inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to two Cu1+ and two Ga3+ atoms to form TeGa2Cu2 tetrahedra that share corners with four equivalent SeGa2Cu2 tetrahedra and corners with eight TeGa2Cu2 tetrahedra. In the second Te2- site, Te2- is bonded to two Cu1+ and two Ga3+ atoms to form TeGa2Cu2 tetrahedra that share corners with six TeGa2Cu2 tetrahedra and corners with six SeGa2Cu2 tetrahedra. In the third Te2- site, Te2- is bonded to two Cu1+ and two Ga3+ atoms to form TeGa2Cu2 tetrahedra that share corners with six TeGa2Cu2 tetrahedra and corners with six SeGa2Cu2 tetrahedra. In the fourth Te2- site, Te2- is bonded to two equivalent Cu1+ and two equivalent Ga3+ atoms to form TeGa2Cu2 tetrahedra that share corners with four equivalent SeGa2Cu2 tetrahedra and corners with eight TeGa2Cu2 tetrahedra. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to two equivalent Cu1+ and two equivalent Ga3+ atoms to form SeGa2Cu2 tetrahedra that share corners with four equivalent SeGa2Cu2 tetrahedra and corners with eight TeGa2Cu2 tetrahedra. In the second Se2- site, Se2- is bonded to two Cu1+ and two Ga3+ atoms to form SeGa2Cu2 tetrahedra that share corners with twelve TeGa2Cu2 tetrahedra. In the third Se2- site, Se2- is bonded to two equivalent Cu1+ and two equivalent Ga3+ atoms to form SeGa2Cu2 tetrahedra that share corners with four equivalent SeGa2Cu2 tetrahedra and corners with eight TeGa2Cu2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TeC4Se4(N4Cl)2 by Materials Project

C2Te(N2Se)2(CN2SeCl)2 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of two CN2SeCl clusters and one C2Te(N2Se)2 ribbon oriented in the (1, 0, 0) direction. In each CN2SeCl cluster, C4+ is bonded in a trigonal planar geometry to two N+1.25- and one Cl1- atom. There is one shorter (1.34 Å) and one longer (1.36 Å) C–N bond length. The C–Cl bond length is 1.70 Å. There are two inequivalent N+1.25- sites. In the first N+1.25- site, N+1.25- is bonded in a 2-coordinate geometry to one C4+ and one Se2- atom. The N–Se bond length is 1.89 Å. In the second N+1.25- site, N+1.25- is bonded in a distorted L-shaped geometry to one C4+ and one Se2- atom. The N–Se bond length is 1.94 Å. Se2- is bonded in a 4-coordinate geometry to two N+1.25- atoms. Cl1- is bonded in a single-bond geometry to one C4+ atom. In the C2Te(N2Se)2 ribbon, C4+ is bonded in a linear geometry to two N+1.25- atoms. There is one shorter (1.20 Å) and one longer (1.28 Å) C–N bond length. There are two inequivalent N+1.25- sites. In the first N+1.25- site, N+1.25- is bonded in a 2-coordinate geometry to one C4+, one Te4+, and one Se2- atom. The N–Te bond length is 2.09 Å. The N–Se bond length is 2.67 Å. In the second N+1.25- site, N+1.25- is bonded in a single-bond geometry to one C4+ atom. Te4+ is bonded in a distorted linear geometry to two equivalent N+1.25- and two equivalent Se2- atoms. Both Te–Se bond lengths are 2.75 Å. Se2- is bonded in a 3-coordinate geometry to one N+1.25-, one Te4+, and one Se2- atom. The Se–Se bond length is 2.33 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tl4GeSe4 by Materials Project

Tl4GeSe4 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are five inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a 4-coordinate geometry to six Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.13–3.71 Å. In the second Tl1+ site, Tl1+ is bonded in a 5-coordinate geometry to six Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.08–4.01 Å. In the third Tl1+ site, Tl1+ is bonded to five Se2- atoms to form distorted TlSe5 square pyramids that share corners with two equivalent TlSe5 square pyramids, corners with three equivalent GeSe4 tetrahedra, and an edgeedge with one GeSe4 tetrahedra. There are a spread of Tl–Se bond distances ranging from 3.18–3.44 Å. In the fourth Tl1+ site, Tl1+ is bonded in a 4-coordinate geometry to six Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.23–3.77 Å. In the fifth Tl1+ site, Tl1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are two shorter (3.08 Å) and two longer (3.34 Å) Tl–Se bond lengths. Ge4+ is bonded to four Se2- atoms to form GeSe4 tetrahedra that share corners with three equivalent TlSe5 square pyramids and an edgeedge with one TlSe5 square pyramid. There are a spread of Ge–Se bond distances ranging from 2.39–2.42 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to five Tl1+ and one Ge4+ atom to form a mixture of distorted corner and edge-sharing SeTl5Ge octahedra. The corner-sharing octahedra tilt angles range from 0–22°. In the second Se2- site, Se2- is bonded to five Tl1+ and one Ge4+ atom to form a mixture of distorted corner and edge-sharing SeTl5Ge octahedra. The corner-sharing octahedra tilt angles range from 0–22°. In the third Se2- site, Se2- is bonded in a 1-coordinate geometry to six Tl1+ and one Ge4+ atom. In the fourth Se2- site, Se2- is bonded in a 1-coordinate geometry to six Tl1+ and one Ge4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pm2MgSe4 by Materials Project

MgPm2Se4 crystallizes in the orthorhombic Pca2_1 space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six Se2- atoms to form MgSe6 octahedra that share a cornercorner with one PmSe6 octahedra, corners with two equivalent MgSe6 octahedra, corners with four PmSe7 pentagonal bipyramids, an edgeedge with one MgSe6 octahedra, edges with four PmSe6 octahedra, and edges with three PmSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 12–53°. There are a spread of Mg–Se bond distances ranging from 2.66–3.04 Å. In the second Mg2+ site, Mg2+ is bonded to six Se2- atoms to form MgSe6 octahedra that share a cornercorner with one PmSe6 octahedra, corners with two equivalent MgSe6 octahedra, corners with four PmSe7 pentagonal bipyramids, an edgeedge with one MgSe6 octahedra, edges with four PmSe6 octahedra, and edges with three PmSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 12–53°. There are a spread of Mg–Se bond distances ranging from 2.68–2.93 Å. There are four inequivalent Pm3+ sites. In the first Pm3+ site, Pm3+ is bonded to six Se2- atoms to form PmSe6 octahedra that share a cornercorner with one MgSe6 octahedra, corners with two equivalent PmSe6 octahedra, corners with four PmSe7 pentagonal bipyramids, an edgeedge with one PmSe6 octahedra, edges with four MgSe6 octahedra, and edges with three PmSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 12–53°. There are a spread of Pm–Se bond distances ranging from 2.88–2.96 Å. In the second Pm3+ site, Pm3+ is bonded to six Se2- atoms to form PmSe6 octahedra that share a cornercorner with one MgSe6 octahedra, corners with two equivalent PmSe6 octahedra, corners with four PmSe7 pentagonal bipyramids, an edgeedge with one PmSe6 octahedra, edges with four MgSe6 octahedra, and edges with three PmSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 12–53°. There are a spread of Pm–Se bond distances ranging from 2.87–2.99 Å. In the third Pm3+ site, Pm3+ is bonded to seven Se2- atoms to form distorted PmSe7 pentagonal bipyramids that share corners with four MgSe6 octahedra, corners with four PmSe6 octahedra, edges with three MgSe6 octahedra, edges with three PmSe6 octahedra, and faces with two equivalent PmSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 14–70°. There are a spread of Pm–Se bond distances ranging from 2.93–3.19 Å. In the fourth Pm3+ site, Pm3+ is bonded to seven Se2- atoms to form distorted PmSe7 pentagonal bipyramids that share corners with four MgSe6 octahedra, corners with four PmSe6 octahedra, edges with three MgSe6 octahedra, edges with three PmSe6 octahedra, and faces with two equivalent PmSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 16–70°. There are a spread of Pm–Se bond distances ranging from 2.92–3.23 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to two Mg2+ and three Pm3+ atoms to form distorted SePm3Mg2 trigonal bipyramids that share corners with two equivalent SePm3Mg2 square pyramids, corners with three equivalent SePm3Mg tetrahedra, corners with two equivalent SePm3Mg2 trigonal bipyramids, edges with five SePm3Mg2 square pyramids, and edges with three SePm3Mg2 trigonal bipyramids. In the second Se2- site, Se2- is bonded to two Mg2+ and three Pm3+ atoms to form distorted SePm3Mg2 trigonal bipyramids that share corners with six SePm3Mg2 square pyramids, corners with two equivalent SePm3Mg tetrahedra, corners with two equivalent SePm3Mg2 trigonal bipyramids, edges with three SePm3Mg2 square pyramids, an edgeedge with one SePm3Mg tetrahedra, and edges with three SePm3Mg2 trigonal bipyramids. In the third Se2- site, Se2- is bonded to one Mg2+ and three Pm3+ atoms to form a mixture of distorted edge and corner-sharing SePm3Mg tetrahedra. In the fourth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Pm3+ atoms. In the fifth Se2- site, Se2- is bonded to two Mg2+ and three Pm3+ atoms to form distorted SePm3Mg2 square pyramids that share a cornercorner with one SePm3Mg tetrahedra, corners with eight SePm3Mg2 trigonal bipyramids, edges with four SePm3Mg2 square pyramids, an edgeedge with one SePm3Mg tetrahedra, and edges with two SePm3Mg2 trigonal bipyramids. In the sixth Se2- site, Se2- is bonded to two Mg2+ and three Pm3+ atoms to form SePm3Mg2 square pyramids that share corners with two equivalent SePm4Mg square pyramids, a cornercorner with one SePm3Mg tetrahedra, corners with six SePm3Mg2 trigonal bipyramids, edges with three SePm3Mg2 square pyramids, an edgeedge with one SePm3Mg tetrahedra, and edges with three SePm3Mg2 trigonal bipyramids. In the seventh Se2- site, Se2- is bonded to one Mg2+ and four Pm3+ atoms to form distorted SePm4Mg square pyramids that share corners with two equivalent SePm3Mg2 square pyramids, corners with two equivalent SePm3Mg tetrahedra, corners with two equivalent SePm4Mg trigonal bipyramids, edges with three SePm3Mg2 square pyramids, an edgeedge with one SePm3Mg tetrahedra, and edges with five SePm3Mg2 trigonal bipyramids. In the eighth Se2- site, Se2- is bonded to one Mg2+ and four Pm3+ atoms to form distorted SePm4Mg trigonal bipyramids that share corners with eight SePm3Mg2 square pyramids, corners with three equivalent SePm3Mg tetrahedra, edges with two SePm3Mg2 square pyramids, and edges with four SePm3Mg2 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on RbGaSnSe4 by Materials Project

RbGaSnSe4 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Rb–Se bond distances ranging from 3.57–4.08 Å. In the second Rb1+ site, Rb1+ is bonded to seven Se2- atoms to form distorted RbSe7 pentagonal bipyramids that share corners with two equivalent RbSe7 pentagonal bipyramids, corners with four GaSe4 tetrahedra, corners with four SnSe4 tetrahedra, edges with two equivalent RbSe7 pentagonal bipyramids, an edgeedge with one GaSe4 tetrahedra, and edges with two SnSe4 tetrahedra. There are a spread of Rb–Se bond distances ranging from 3.62–3.89 Å. There are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share corners with three equivalent RbSe7 pentagonal bipyramids, corners with two equivalent GaSe4 tetrahedra, and corners with two SnSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.43–2.50 Å. In the second Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share a cornercorner with one RbSe7 pentagonal bipyramid, corners with two equivalent GaSe4 tetrahedra, corners with two SnSe4 tetrahedra, and an edgeedge with one RbSe7 pentagonal bipyramid. There are a spread of Ga–Se bond distances ranging from 2.43–2.49 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 RbSe7 pentagonal bipyramids, corners with two GaSe4 tetrahedra, an edgeedge with one RbSe7 pentagonal bipyramid, and an edgeedge with one SnSe4 tetrahedra. There are a spread of Sn–Se bond distances ranging from 2.54–2.63 Å. In the second Sn4+ site, Sn4+ is bonded to four Se2- atoms to form SnSe4 tetrahedra that share corners with two equivalent RbSe7 pentagonal bipyramids, corners with two GaSe4 tetrahedra, an edgeedge with one RbSe7 pentagonal bipyramid, and an edgeedge with one SnSe4 tetrahedra. There are a spread of Sn–Se bond distances ranging from 2.55–2.62 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to three equivalent Rb1+ and two Sn4+ atoms. In the second Se2- site, Se2- is bonded in a 2-coordinate geometry to one Rb1+, one Ga3+, and one Sn4+ atom. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to one Rb1+, one Ga3+, and one Sn4+ atom. In the fourth Se2- site, Se2- is bonded in a 2-coordinate geometry to two equivalent Rb1+ and two Sn4+ atoms. In the fifth Se2- site, Se2- is bonded in a 2-coordinate geometry to two Rb1+ and two Ga3+ atoms. In the sixth Se2- site, Se2- is bonded in a 2-coordinate geometry to two Rb1+, one Ga3+, and one Sn4+ atom. In the seventh Se2- site, Se2- is bonded in a 2-coordinate geometry to three Rb1+, one Ga3+, and one Sn4+ atom. In the eighth Se2- site, Se2- is bonded in a distorted water-like geometry to one Rb1+ and two Ga3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb3CuSe6 by Materials Project

Tb3CuSe6 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent Tb+3.33+ sites. In the first Tb+3.33+ site, Tb+3.33+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Tb–Se bond distances ranging from 2.79–3.11 Å. In the second Tb+3.33+ site, Tb+3.33+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Tb–Se bond distances ranging from 2.94–3.10 Å. In the third Tb+3.33+ site, Tb+3.33+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Tb–Se bond distances ranging from 2.93–3.18 Å. Cu2+ is bonded to four Se2- atoms to form distorted edge-sharing CuSe4 trigonal pyramids. There are a spread of Cu–Se bond distances ranging from 2.40–2.58 Å. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to four Tb+3.33+ and one Cu2+ atom. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to four Tb+3.33+ and two equivalent Cu2+ atoms. In the third Se2- site, Se2- is bonded in a 5-coordinate geometry to four Tb+3.33+ and one Cu2+ atom. In the fourth Se2- site, Se2- is bonded to four Tb+3.33+ atoms to form distorted corner-sharing SeTb4 trigonal pyramids. In the fifth Se2- site, Se2- is bonded in a 5-coordinate geometry to four Tb+3.33+ and one Se2- atom. The Se–Se bond length is 2.46 Å. In the sixth Se2- site, Se2- is bonded in a 6-coordinate geometry to four Tb+3.33+ and one Se2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn2CrGa3Se8 by Materials Project

CrMnGaSe4MnGa2Se4 crystallizes in the trigonal R3m space group. The structure is two-dimensional and consists of three CrMnGaSe4 sheets oriented in the (0, 0, 1) direction and three MnGa2Se4 sheets oriented in the (0, 0, 1) direction. In each CrMnGaSe4 sheet, Cr3+ is bonded to four Se2- atoms to form CrSe4 tetrahedra that share corners with three equivalent GaSe6 octahedra and corners with six equivalent CrSe4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. All Cr–Se bond lengths are 2.46 Å. Mn2+ is bonded to four Se2- atoms to form MnSe4 tetrahedra that share corners with three equivalent GaSe6 octahedra and corners with six equivalent MnSe4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. There are three shorter (2.46 Å) and one longer (2.52 Å) Mn–Se bond lengths. Ga3+ is bonded to six Se2- atoms to form GaSe6 octahedra that share corners with three equivalent CrSe4 tetrahedra, corners with three equivalent MnSe4 tetrahedra, and edges with six equivalent GaSe6 octahedra. There are three shorter (2.64 Å) and three longer (2.67 Å) Ga–Se bond lengths. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to three equivalent Cr3+ atoms. In the second Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to three equivalent Mn2+ atoms. In the third Se2- site, Se2- is bonded to one Cr3+ and three equivalent Ga3+ atoms to form a mixture of distorted edge and corner-sharing SeCrGa3 trigonal pyramids. In the fourth Se2- site, Se2- is bonded to one Mn2+ and three equivalent Ga3+ atoms to form distorted SeMnGa3 trigonal pyramids that share corners with nine SeMnGa3 trigonal pyramids and edges with three equivalent SeCrGa3 trigonal pyramids. In each MnGa2Se4 sheet, Mn2+ is bonded to four Se2- atoms to form MnSe4 tetrahedra that share corners with three equivalent GaSe6 octahedra and corners with six equivalent MnSe4 tetrahedra. The corner-sharing octahedral tilt angles are 60°. There are three shorter (2.45 Å) and one longer (2.55 Å) Mn–Se bond lengths. There are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to six Se2- atoms to form GaSe6 octahedra that share corners with three equivalent MnSe4 tetrahedra, corners with three equivalent GaSe4 tetrahedra, and edges with six equivalent GaSe6 octahedra. There are three shorter (2.61 Å) and three longer (2.70 Å) Ga–Se bond lengths. In the second Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share corners with three equivalent GaSe6 octahedra and corners with six equivalent GaSe4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. There are one shorter (2.42 Å) and three longer (2.50 Å) Ga–Se bond lengths. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to three equivalent Ga3+ atoms. In the second Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to three equivalent Mn2+ atoms. In the third Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to four Ga3+ atoms. In the fourth Se2- site, Se2- is bonded to one Mn2+ and three equivalent Ga3+ atoms to form distorted corner-sharing SeMnGa3 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSe2(NO7)2 by Materials Project

MgSe2(NO7)2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one MgSe2(NO7)2 sheet oriented in the (1, 0, 0) direction. Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent SeO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.00–2.28 Å. N is bonded in a bent 120 degrees geometry to two O atoms. There is one shorter (1.25 Å) and one longer (1.27 Å) N–O bond length. Se is bonded to four O atoms to form distorted SeO4 tetrahedra that share a cornercorner with one MgO6 octahedra. The corner-sharing octahedral tilt angles are 30°. There are a spread of Se–O bond distances ranging from 1.63–2.16 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to one Mg and one O atom. The O–O bond length is 1.23 Å. In the second O site, O is bonded in a bent 150 degrees geometry to one Mg and one Se atom. In the third O site, O is bonded in a single-bond geometry to one Se atom. In the fourth O site, O is bonded in a bent 120 degrees geometry to one N and one Se atom. In the fifth O site, O is bonded in a single-bond geometry to one Se atom. In the sixth O site, O is bonded in a bent 120 degrees geometry to one Mg and one N atom. In the seventh O site, O is bonded in a single-bond geometry to one O atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SeO4 by Materials Project

SeO4 is Silicon tetrafluoride-like structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four SeO4 clusters. Se is bonded in a tetrahedral geometry to four O atoms. There is one shorter (1.67 Å) and three longer (1.69 Å) Se–O bond length. There are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Se atom. In the second O site, O is bonded in a single-bond geometry to one Se atom. In the third O site, O is bonded in a single-bond geometry to one Se atom. In the fourth O site, O is bonded in a single-bond geometry to one Se atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CrGa3(CoSe4)2 by Materials Project

CrGa3(CoSe4)2 crystallizes in the monoclinic Cm space group. The structure is two-dimensional and consists of two CrGa3(CoSe4)2 sheets oriented in the (1, 0, 0) direction. Cr3+ is bonded to four Se2- atoms to form CrSe4 tetrahedra that share corners with three GaSe6 octahedra, corners with two equivalent CrSe4 tetrahedra, and corners with four equivalent GaSe4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–57°. There are a spread of Cr–Se bond distances ranging from 2.42–2.47 Å. There are two inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to four Se2- atoms to form CoSe4 tetrahedra that share corners with three GaSe6 octahedra and corners with six CoSe4 tetrahedra. The corner-sharing octahedral tilt angles are 58°. There are a spread of Co–Se bond distances ranging from 2.31–2.34 Å. In the second Co2+ site, Co2+ is bonded to four Se2- atoms to form CoSe4 tetrahedra that share corners with three GaSe6 octahedra and corners with six CoSe4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–57°. There are one shorter (2.30 Å) and three longer (2.31 Å) Co–Se bond lengths. There are three inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to six Se2- atoms to form GaSe6 octahedra that share a cornercorner with one GaSe4 tetrahedra, corners with two equivalent CrSe4 tetrahedra, corners with three CoSe4 tetrahedra, and edges with six GaSe6 octahedra. There are a spread of Ga–Se bond distances ranging from 2.60–2.66 Å. In the second Ga3+ site, Ga3+ is bonded to six Se2- atoms to form GaSe6 octahedra that share a cornercorner with one CrSe4 tetrahedra, corners with two equivalent GaSe4 tetrahedra, corners with three CoSe4 tetrahedra, and edges with six GaSe6 octahedra. There are a spread of Ga–Se bond distances ranging from 2.59–2.64 Å. In the third Ga3+ site, Ga3+ is bonded to four Se2- atoms to form GaSe4 tetrahedra that share corners with three GaSe6 octahedra, corners with two equivalent GaSe4 tetrahedra, and corners with four equivalent CrSe4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–57°. There are three shorter (2.44 Å) and one longer (2.45 Å) Ga–Se bond lengths. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to one Cr3+ and two equivalent Ga3+ atoms. In the second Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to two equivalent Cr3+ and one Ga3+ atom. In the third Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to three Co2+ atoms. In the fourth Se2- site, Se2- is bonded in a trigonal non-coplanar geometry to three Co2+ atoms. In the fifth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to one Cr3+ and three Ga3+ atoms. In the sixth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to four Ga3+ atoms. In the seventh Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to one Co2+ and three Ga3+ atoms. In the eighth Se2- site, Se2- is bonded to one Co2+ and three Ga3+ atoms to form distorted corner-sharing SeGa3Co trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re6Se8O7F6 by Materials Project

(Re3Se4OF3)4(O2)5 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of four hydrogen peroxide molecules; four trioxidane molecules; and two Re3Se4OF3 sheets oriented in the (1, 0, 0) direction. In each Re3Se4OF3 sheet, there are three inequivalent Re6+ sites. In the first Re6+ site, Re6+ is bonded in a distorted single-bond geometry to three Se2- and one F1- atom. There are a spread of Re–Se bond distances ranging from 2.46–2.55 Å. The Re–F bond length is 1.94 Å. In the second Re6+ site, Re6+ is bonded in a distorted single-bond geometry to three Se2- and one F1- atom. There are a spread of Re–Se bond distances ranging from 2.58–2.67 Å. The Re–F bond length is 1.94 Å. In the third Re6+ site, Re6+ is bonded in a distorted single-bond geometry to three Se2- and one F1- atom. There are a spread of Re–Se bond distances ranging from 2.48–2.60 Å. The Re–F bond length is 1.94 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 9-coordinate geometry to three Re6+ atoms. In the second Se2- site, Se2- is bonded in a 1-coordinate geometry to three Re6+ and one F1- atom. The Se–F bond length is 3.24 Å. In the third Se2- site, Se2- is bonded in a distorted single-bond geometry to one O2- atom. The Se–O bond length is 1.68 Å. In the fourth Se2- site, Se2- is bonded in a 1-coordinate geometry to three Re6+ and one O2- atom. The Se–O bond length is 3.14 Å. O2- is bonded in a single-bond geometry to two Se2- atoms. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Re6+ and one Se2- atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Re6+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one Re6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cs2Bi4Se7 by Materials Project

Cs2Bi4Se7 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.58–3.91 Å. In the second Cs1+ site, Cs1+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.61–3.84 Å. There are four inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ 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 4–7°. There are a spread of Bi–Se bond distances ranging from 2.83–3.19 Å. In the second Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of corner and edge-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 7°. There are a spread of Bi–Se bond distances ranging from 2.89–3.08 Å. In the third Bi3+ site, Bi3+ 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 4–11°. There are a spread of Bi–Se bond distances ranging from 2.82–3.22 Å. In the fourth Bi3+ site, Bi3+ is bonded to six Se2- atoms to form a mixture of corner and edge-sharing BiSe6 octahedra. The corner-sharing octahedral tilt angles are 11°. There are a spread of Bi–Se bond distances ranging from 2.87–3.09 Å. There are seven inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to three Cs1+ and three equivalent Bi3+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to three equivalent Cs1+ and two equivalent Bi3+ atoms. In the third Se2- site, Se2- is bonded to two equivalent Cs1+ and three Bi3+ atoms to form SeCs2Bi3 square pyramids that share a cornercorner with one SeBi6 octahedra, corners with six SeCs2Bi3 trigonal bipyramids, edges with four SeCs3Bi3 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 fourth Se2- site, Se2- is bonded to three Cs1+ and three Bi3+ atoms to form distorted SeCs3Bi3 octahedra that share corners with two equivalent SeBi6 octahedra, corners with five SeCs2Bi3 trigonal bipyramids, edges with five SeBi6 octahedra, and edges with two equivalent SeCs2Bi3 square pyramids. The corner-sharing octahedral tilt angles are 6°. In the fifth Se2- site, Se2- is bonded to two equivalent Cs1+ and three Bi3+ atoms to form distorted SeCs2Bi3 trigonal bipyramids that share corners with three SeBi6 octahedra, corners with four equivalent SeCs2Bi3 square pyramids, an edgeedge with one SeCs2Bi3 square pyramid, and edges with four SeCs2Bi3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 2–41°. In the sixth Se2- site, Se2- is bonded to one Cs1+ and four Bi3+ atoms to form SeCsBi4 trigonal bipyramids that share corners with three equivalent SeCs3Bi3 octahedra, corners with two equivalent SeCs2Bi3 square pyramids, corners with two equivalent SeCsBi4 trigonal bipyramids, edges with two equivalent SeBi6 octahedra, an edgeedge with one SeCs2Bi3 square pyramid, and edges with two equivalent SeCs2Bi3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 8–34°. In the seventh Se2- site, Se2- is bonded to six Bi3+ atoms to form SeBi6 octahedra that share corners with two equivalent SeCs3Bi3 octahedra, a cornercorner with one SeCs2Bi3 square pyramid, a cornercorner with one SeCs2Bi3 trigonal bipyramid, edges with seven SeCs3Bi3 octahedra, edges with two equivalent SeCs2Bi3 square pyramids, and edges with two equivalent SeCsBi4 trigonal bipyramids. The corner-sharing octahedral tilt angles are 6°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn2Se3(NO6)2 by Materials Project

Mn2(SeO4)3N2 crystallizes in the cubic P2_13 space group. The structure is three-dimensional and consists of eight ammonia molecules and one Mn2(SeO4)3 framework. In the Mn2(SeO4)3 framework, there are two inequivalent Mn7+ sites. In the first Mn7+ site, Mn7+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six equivalent SeO4 tetrahedra. There are three shorter (2.03 Å) and three longer (2.06 Å) Mn–O bond lengths. In the second Mn7+ site, Mn7+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six equivalent SeO4 tetrahedra. There are three shorter (2.04 Å) and three longer (2.06 Å) Mn–O bond lengths. Se is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with four MnO6 octahedra. The corner-sharing octahedra tilt angles range from 16–51°. There are a spread of Se–O bond distances ranging from 1.66–1.69 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Mn7+ and one Se atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Mn7+ and one Se atom. In the third O2- site, O2- is bonded in a linear geometry to one Mn7+ and one Se atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Mn7+ and one Se atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Er2MgSe4 by Materials Project

MgEr2Se4 crystallizes in the orthorhombic Pca2_1 space group. The structure is three-dimensional. there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six Se2- atoms to form MgSe6 octahedra that share a cornercorner with one ErSe6 octahedra, corners with two equivalent MgSe6 octahedra, corners with four ErSe7 pentagonal bipyramids, an edgeedge with one MgSe6 octahedra, edges with four ErSe6 octahedra, and edges with three ErSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 13–54°. There are a spread of Mg–Se bond distances ranging from 2.66–2.96 Å. In the second Mg2+ site, Mg2+ is bonded to six Se2- atoms to form MgSe6 octahedra that share a cornercorner with one ErSe6 octahedra, corners with two equivalent MgSe6 octahedra, corners with four ErSe7 pentagonal bipyramids, an edgeedge with one MgSe6 octahedra, edges with four ErSe6 octahedra, and edges with three ErSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 13–54°. There are a spread of Mg–Se bond distances ranging from 2.70–2.87 Å. There are four inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded to six Se2- atoms to form ErSe6 octahedra that share a cornercorner with one MgSe6 octahedra, corners with two equivalent ErSe6 octahedra, corners with four ErSe7 pentagonal bipyramids, an edgeedge with one ErSe6 octahedra, edges with four MgSe6 octahedra, and edges with three ErSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 12–54°. There are a spread of Er–Se bond distances ranging from 2.80–2.87 Å. In the second Er3+ site, Er3+ is bonded to six Se2- atoms to form ErSe6 octahedra that share a cornercorner with one MgSe6 octahedra, corners with two equivalent ErSe6 octahedra, corners with four ErSe7 pentagonal bipyramids, an edgeedge with one ErSe6 octahedra, edges with four MgSe6 octahedra, and edges with three ErSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 12–54°. There are a spread of Er–Se bond distances ranging from 2.79–2.90 Å. In the third Er3+ site, Er3+ is bonded to seven Se2- atoms to form distorted ErSe7 pentagonal bipyramids that share corners with four MgSe6 octahedra, corners with four ErSe6 octahedra, edges with three MgSe6 octahedra, edges with three ErSe6 octahedra, and faces with two equivalent ErSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 16–69°. There are a spread of Er–Se bond distances ranging from 2.84–3.13 Å. In the fourth Er3+ site, Er3+ is bonded to seven Se2- atoms to form distorted ErSe7 pentagonal bipyramids that share corners with four MgSe6 octahedra, corners with four ErSe6 octahedra, edges with three MgSe6 octahedra, edges with three ErSe6 octahedra, and faces with two equivalent ErSe7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 17–67°. There are a spread of Er–Se bond distances ranging from 2.83–3.15 Å. There are eight inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to two Mg2+ and three Er3+ atoms to form distorted SeEr3Mg2 trigonal bipyramids that share corners with two equivalent SeEr3Mg2 square pyramids, corners with three equivalent SeEr3Mg tetrahedra, corners with two equivalent SeEr3Mg2 trigonal bipyramids, edges with five SeEr3Mg2 square pyramids, and edges with three SeEr3Mg2 trigonal bipyramids. In the second Se2- site, Se2- is bonded to two Mg2+ and three Er3+ atoms to form distorted SeEr3Mg2 trigonal bipyramids that share corners with six SeEr3Mg2 square pyramids, corners with two equivalent SeEr3Mg tetrahedra, corners with two equivalent SeEr3Mg2 trigonal bipyramids, edges with three SeEr3Mg2 square pyramids, an edgeedge with one SeEr3Mg tetrahedra, and edges with three SeEr3Mg2 trigonal bipyramids. In the third Se2- site, Se2- is bonded to one Mg2+ and three Er3+ atoms to form a mixture of distorted edge and corner-sharing SeEr3Mg tetrahedra. In the fourth Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three Er3+ atoms. In the fifth Se2- site, Se2- is bonded to two Mg2+ and three Er3+ atoms to form distorted SeEr3Mg2 square pyramids that share a cornercorner with one SeEr3Mg tetrahedra, corners with eight SeEr3Mg2 trigonal bipyramids, edges with four SeEr3Mg2 square pyramids, an edgeedge with one SeEr3Mg tetrahedra, and edges with two SeEr3Mg2 trigonal bipyramids. In the sixth Se2- site, Se2- is bonded to two Mg2+ and three Er3+ atoms to form distorted SeEr3Mg2 square pyramids that share corners with two equivalent SeEr4Mg square pyramids, a cornercorner with one SeEr3Mg tetrahedra, corners with six SeEr3Mg2 trigonal bipyramids, edges with three SeEr3Mg2 square pyramids, an edgeedge with one SeEr3Mg tetrahedra, and edges with three SeEr3Mg2 trigonal bipyramids. In the seventh Se2- site, Se2- is bonded to one Mg2+ and four Er3+ atoms to form distorted SeEr4Mg square pyramids that share corners with two equivalent SeEr3Mg2 square pyramids, corners with two equivalent SeEr3Mg tetrahedra, corners with two equivalent SeEr4Mg trigonal bipyramids, edges with three SeEr3Mg2 square pyramids, an edgeedge with one SeEr3Mg tetrahedra, and edges with five SeEr3Mg2 trigonal bipyramids. In the eighth Se2- site, Se2- is bonded to one Mg2+ and four Er3+ atoms to form distorted SeEr4Mg trigonal bipyramids that share corners with eight SeEr3Mg2 square pyramids, corners with three equivalent SeEr3Mg tetrahedra, edges with two SeEr3Mg2 square pyramids, and edges with four SeEr3Mg2 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li2SeO4 by Materials Project

Li2SeO4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are twelve inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 2.01–2.60 Å. In the second Li1+ site, Li1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Li–O bond distances ranging from 1.96–2.73 Å. In the third Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two SeO4 tetrahedra and a cornercorner with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 2.00–2.26 Å. In the fourth Li1+ site, Li1+ is bonded in a distorted see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.89–2.18 Å. In the fifth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share a cornercorner with one LiO4 tetrahedra and an edgeedge with one SeO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.98–2.09 Å. In the sixth Li1+ site, Li1+ is bonded in a distorted see-saw-like geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.89–2.15 Å. In the seventh Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 1.96–2.44 Å. In the eighth Li1+ site, Li1+ is bonded in a distorted trigonal planar geometry to three O2- atoms. There are a spread of Li–O bond distances ranging from 1.88–1.94 Å. In the ninth Li1+ site, Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share a cornercorner with one LiO4 tetrahedra and an edgeedge with one SeO4 tetrahedra. There are a spread of Li–O bond distances ranging from 2.00–2.09 Å. In the tenth Li1+ site, Li1+ is bonded to four O2- atoms to form LiO4 tetrahedra that share corners with two SeO4 tetrahedra and a cornercorner with one LiO4 trigonal pyramid. There are a spread of Li–O bond distances ranging from 2.04–2.23 Å. In the eleventh Li1+ site, Li1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Li–O bond distances ranging from 2.00–2.52 Å. In the twelfth Li1+ site, Li1+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Li–O bond distances ranging from 1.86–1.94 Å. There are six inequivalent Se6+ sites. In the first Se6+ site, Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra. There are a spread of Se–O bond distances ranging from 1.66–1.69 Å. In the second Se6+ site, Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra. There is two shorter (1.67 Å) and two longer (1.68 Å) Se–O bond length. In the third Se6+ site, Se6+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.71–1.77 Å. In the fourth Se6+ site, Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Se–O bond distances ranging from 1.66–1.70 Å. In the fifth Se6+ site, Se6+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.71–1.77 Å. In the sixth Se6+ site, Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share a cornercorner with one LiO4 tetrahedra and an edgeedge with one LiO4 trigonal pyramid. There are a spread of Se–O bond distances ranging from 1.66–1.70 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Li1+ and one Se6+ atom. In the second O2- site, O2- is bonded in a T-shaped geometry to two Li1+ and one Se6+ atom. In the third O2- site, O2- is bonded in a tetrahedral geometry to three Li1+ and one Se6+ atom. In the fourth O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one Se6+ atom. In the fifth O2- site, O2- is bonded to three Li1+ and one Se6+ atom to form distorted edge-sharing OLi3Se tetrahedra. In the sixth O2- site, O2- is bonded in a distorted L-shaped geometry to one Li1+ and one Se6+ atom. In the seventh O2- site, O2- is bonded in a distorted T-shaped geometry to two Li1+ and one Se6+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+ and one O2- atom. The O–O bond length is 1.24 Å. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two Li1+ and one Se6+ atom. In the tenth O2- site, O2- is bonded in a distorted T-shaped geometry to two Li1+ and one Se6+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+ and one O2- atom. In the twelfth O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one Se6+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Li1+ and one Se6+ atom. In the fourteenth O2- site, O2- is bonded in a distorted T-shaped geometry to two Li1+ and one Se6+ atom. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Li1+ and one Se6+ atom. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Li1+ and one Se6+ atom. In the seventeenth O2- site, O2- is bonded in a distorted T-shaped geometry to two Li1+ and one Se6+ atom. In the eighteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Li1+ and one Se6+ atom. In the nineteenth O2- site, O2- is bonded in an L-shaped geometry to one Li1+ and one Se6+ atom. In the twentieth O2- site, O2- is bonded in a distorted T-shaped geometry to two Li1+ and one Se6+ atom. In the twenty-first O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one Se6+ atom. In the twenty-second O2- site, O2- is bonded to three Li1+ and one Se6+ atom to form edge-sharing OLi3Se tetrahedra. In the twenty-third O2- site, O2- is bonded in a trigonal planar geometry to two Li1+ and one Se6+ atom. In the twenty-fourth O2- site, O2- is bonded in a 3-coordinate geometry to two Li1+ and one Se6+ atom.

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