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DOE OSTI2020

Materials Data on Te3Pd5 by Materials Project

Pd5Te3 crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. there are two inequivalent Pd sites. In the first Pd site, Pd is bonded in a 5-coordinate geometry to one Pd and four Te atoms. The Pd–Pd bond length is 2.60 Å. There are one shorter (2.58 Å) and three longer (2.99 Å) Pd–Te bond lengths. In the second Pd site, Pd is bonded in a body-centered cubic geometry to four equivalent Pd and four equivalent Te atoms. All Pd–Te bond lengths are 2.59 Å. There are two inequivalent Te sites. In the first Te site, Te is bonded in a 8-coordinate geometry to eight Pd atoms. In the second Te site, Te is bonded in a tetrahedral geometry to four equivalent Pd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta6TeSe2 by Materials Project

Ta6TeSe2 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one Ta6TeSe2 sheet oriented in the (0, 0, 1) direction. there are six inequivalent Ta sites. In the first Ta site, Ta is bonded in a 2-coordinate geometry to two equivalent Ta, two equivalent Te, and two Se atoms. Both Ta–Ta bond lengths are 2.88 Å. Both Ta–Te bond lengths are 2.89 Å. Both Ta–Se bond lengths are 2.71 Å. In the second Ta site, Ta is bonded in a 4-coordinate geometry to one Ta, one Te, and three Se atoms. The Ta–Ta bond length is 2.87 Å. The Ta–Te bond length is 2.92 Å. All Ta–Se bond lengths are 2.70 Å. In the third Ta site, Ta is bonded in a 4-coordinate geometry to one Ta, one Te, and three Se atoms. The Ta–Ta bond length is 2.88 Å. The Ta–Te bond length is 2.91 Å. There are one shorter (2.69 Å) and two longer (2.70 Å) Ta–Se bond lengths. In the fourth Ta site, Ta is bonded in a distorted single-bond geometry to two equivalent Ta and one Se atom. Both Ta–Ta bond lengths are 2.86 Å. The Ta–Se bond length is 2.83 Å. In the fifth Ta site, Ta is bonded in a 9-coordinate geometry to eight Ta and one Te atom. There are one shorter (2.88 Å) and one longer (2.89 Å) Ta–Ta bond lengths. The Ta–Te bond length is 3.19 Å. In the sixth Ta site, Ta is bonded in a distorted single-bond geometry to one Ta and one Se atom. The Ta–Se bond length is 2.85 Å. Te is bonded in a 5-coordinate geometry to five Ta atoms. There are two inequivalent Se sites. In the first Se site, Se is bonded in a 5-coordinate geometry to five Ta atoms. In the second Se site, Se is bonded in a 5-coordinate geometry to five Ta atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KCeAgTe4 by Materials Project

KCeAgTe4 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Te2- atoms. There are a spread of K–Te bond distances ranging from 3.45–3.82 Å. In the second K1+ site, K1+ is bonded in a 8-coordinate geometry to eight Te2- atoms. There are a spread of K–Te bond distances ranging from 3.45–3.82 Å. There are two inequivalent Ce4+ sites. In the first Ce4+ site, Ce4+ is bonded in a 9-coordinate geometry to nine Te2- atoms. There are a spread of Ce–Te bond distances ranging from 3.25–3.29 Å. In the second Ce4+ site, Ce4+ is bonded in a 9-coordinate geometry to nine Te2- atoms. There are a spread of Ce–Te bond distances ranging from 3.26–3.29 Å. Ag3+ is bonded to four Te2- atoms to form a mixture of edge and corner-sharing AgTe4 tetrahedra. There are three shorter (2.86 Å) and one longer (2.87 Å) Ag–Te bond lengths. There are eight inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to five Ce4+ atoms to form a mixture of distorted edge and corner-sharing TeCe5 trigonal bipyramids. In the second Te2- site, Te2- is bonded in a 8-coordinate geometry to four equivalent K1+ and four equivalent Ag3+ atoms. In the third Te2- site, Te2- is bonded in a 8-coordinate geometry to two equivalent K1+, two equivalent Ce4+, and four equivalent Te2- atoms. All Te–Te bond lengths are 3.16 Å. In the fourth Te2- site, Te2- is bonded to five Ce4+ atoms to form a mixture of distorted edge and corner-sharing TeCe5 trigonal bipyramids. In the fifth Te2- site, Te2- is bonded in a 8-coordinate geometry to two equivalent K1+, two equivalent Ce4+, and four equivalent Te2- atoms. All Te–Te bond lengths are 3.16 Å. In the sixth Te2- site, Te2- is bonded in a 8-coordinate geometry to four equivalent K1+ and four equivalent Ag3+ atoms. In the seventh Te2- site, Te2- is bonded in a 8-coordinate geometry to two equivalent K1+, two equivalent Ce4+, and four equivalent Te2- atoms. In the eighth Te2- site, Te2- is bonded in a 8-coordinate geometry to two equivalent K1+, two equivalent Ce4+, and four equivalent Te2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on FeNiTe4 by Materials Project

FeNiTe4 is pyrite-derived structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Fe3+ is bonded to six Te+1.75- atoms to form FeTe6 octahedra that share corners with four equivalent FeTe6 octahedra and corners with eight equivalent NiTe6 octahedra. The corner-sharing octahedra tilt angles range from 60–63°. There are a spread of Fe–Te bond distances ranging from 2.54–2.59 Å. Ni4+ is bonded to six Te+1.75- atoms to form NiTe6 octahedra that share corners with four equivalent NiTe6 octahedra and corners with eight equivalent FeTe6 octahedra. The corner-sharing octahedra tilt angles range from 60–64°. There are four shorter (2.64 Å) and two longer (2.67 Å) Ni–Te bond lengths. There are two inequivalent Te+1.75- sites. In the first Te+1.75- site, Te+1.75- is bonded in a 3-coordinate geometry to one Fe3+ and two equivalent Ni4+ atoms. In the second Te+1.75- site, Te+1.75- is bonded in a 3-coordinate geometry to two equivalent Fe3+ and one Ni4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho6MnTe2 by Materials Project

Ho6MnTe2 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Ho sites. In the first Ho site, Ho is bonded in a 5-coordinate geometry to one Mn and four equivalent Te atoms. The Ho–Mn bond length is 3.25 Å. All Ho–Te bond lengths are 3.26 Å. In the second Ho site, Ho is bonded in a 5-coordinate geometry to one Mn and four equivalent Te atoms. The Ho–Mn bond length is 3.26 Å. All Ho–Te bond lengths are 3.26 Å. In the third Ho site, Ho is bonded in a 4-coordinate geometry to two equivalent Mn and two equivalent Te atoms. Both Ho–Mn bond lengths are 2.83 Å. Both Ho–Te bond lengths are 3.22 Å. In the fourth Ho site, Ho is bonded in a 4-coordinate geometry to two equivalent Mn and two equivalent Te atoms. Both Ho–Mn bond lengths are 2.83 Å. Both Ho–Te bond lengths are 3.22 Å. Mn is bonded in a 9-coordinate geometry to nine Ho atoms. Te is bonded in a 9-coordinate geometry to nine Ho atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AgSbTe2 by Materials Project

AgSbTe2 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional and consists of one antimony molecule and one Ag2SbTe4 framework. In the Ag2SbTe4 framework, Ag1+ is bonded in a square co-planar geometry to four Te2- atoms. There are two shorter (3.03 Å) and two longer (3.07 Å) Ag–Te bond lengths. Sb3+ is bonded in a square co-planar geometry to four Te2- atoms. All Sb–Te bond lengths are 3.07 Å. There are four inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to two equivalent Ag1+, two equivalent Sb3+, and two equivalent Te2- atoms to form TeAg2Sb2Te2 octahedra that share corners with six equivalent TeAg2Sb2Te2 octahedra and edges with eight TeAg4Te2 octahedra. The corner-sharing octahedral tilt angles are 0°. Both Te–Te bond lengths are 3.07 Å. In the second Te2- site, Te2- is bonded to four equivalent Ag1+ and two equivalent Te2- atoms to form TeAg4Te2 octahedra that share corners with six equivalent TeAg4Te2 octahedra and edges with eight TeAg2Sb2Te2 octahedra. The corner-sharing octahedral tilt angles are 0°. Both Te–Te bond lengths are 3.03 Å. In the third Te2- site, Te2- is bonded to two equivalent Ag1+, two equivalent Sb3+, and two equivalent Te2- atoms to form a mixture of edge and corner-sharing TeAg2Sb2Te2 octahedra. The corner-sharing octahedral tilt angles are 0°. Both Te–Ag bond lengths are 3.03 Å. Both Te–Te bond lengths are 3.07 Å. In the fourth Te2- site, Te2- is bonded to six Te2- atoms to form corner-sharing TeTe6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaGa6AgTe10 by Materials Project

NaAgGa6Te10 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six Te2- atoms to form distorted NaTe6 octahedra that share corners with two equivalent NaTe6 octahedra and corners with twelve GaTe4 tetrahedra. The corner-sharing octahedral tilt angles are 29°. There are two shorter (3.35 Å) and four longer (3.39 Å) Na–Te bond lengths. In the second Na1+ site, Na1+ is bonded to six Te2- atoms to form distorted NaTe6 octahedra that share corners with two equivalent NaTe6 octahedra, corners with four GaTe4 tetrahedra, and edges with four GaTe4 tetrahedra. The corner-sharing octahedral tilt angles are 29°. There are a spread of Na–Te bond distances ranging from 3.21–3.36 Å. Ag1+ is bonded in a 4-coordinate geometry to four Te2- atoms. There are a spread of Ag–Te bond distances ranging from 2.87–3.19 Å. There are six inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four Te2- atoms to form GaTe4 tetrahedra that share corners with two NaTe6 octahedra and corners with six GaTe4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–75°. There are a spread of Ga–Te bond distances ranging from 2.65–2.72 Å. In the second Ga3+ site, Ga3+ is bonded to four Te2- atoms to form GaTe4 tetrahedra that share a cornercorner with one NaTe6 octahedra and corners with six GaTe4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. There are three shorter (2.67 Å) and one longer (2.72 Å) Ga–Te bond lengths. In the third Ga3+ site, Ga3+ is bonded to four Te2- atoms to form GaTe4 tetrahedra that share a cornercorner with one NaTe6 octahedra, corners with six GaTe4 tetrahedra, and an edgeedge with one NaTe6 octahedra. The corner-sharing octahedral tilt angles are 55°. There are a spread of Ga–Te bond distances ranging from 2.65–2.72 Å. In the fourth Ga3+ site, Ga3+ is bonded to four Te2- atoms to form GaTe4 tetrahedra that share a cornercorner with one NaTe6 octahedra, corners with four GaTe4 tetrahedra, and an edgeedge with one GaTe4 tetrahedra. The corner-sharing octahedral tilt angles are 79°. There are a spread of Ga–Te bond distances ranging from 2.60–2.73 Å. In the fifth Ga3+ site, Ga3+ is bonded to four Te2- atoms to form GaTe4 tetrahedra that share a cornercorner with one NaTe6 octahedra, corners with four GaTe4 tetrahedra, an edgeedge with one NaTe6 octahedra, and an edgeedge with one GaTe4 tetrahedra. The corner-sharing octahedral tilt angles are 79°. There are a spread of Ga–Te bond distances ranging from 2.63–2.72 Å. In the sixth Ga3+ site, Ga3+ is bonded to four Te2- atoms to form GaTe4 tetrahedra that share corners with two NaTe6 octahedra, corners with four GaTe4 tetrahedra, and an edgeedge with one GaTe4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–79°. There are a spread of Ga–Te bond distances ranging from 2.61–2.72 Å. There are eleven inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a distorted trigonal non-coplanar geometry to three Ga3+ atoms. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ga3+ atoms. In the third Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ga3+ atoms. In the fourth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ga3+ atoms. In the fifth Te2- site, Te2- is bonded in a rectangular see-saw-like geometry to one Na1+, one Ag1+, and two Ga3+ atoms. In the sixth Te2- site, Te2- is bonded in a rectangular see-saw-like geometry to one Na1+, one Ag1+, and two Ga3+ atoms. In the seventh Te2- site, Te2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+ and two Ga3+ atoms. In the eighth Te2- site, Te2- is bonded in a 3-coordinate geometry to one Na1+ and two Ga3+ atoms. In the ninth Te2- site, Te2- is bonded in an L-shaped geometry to two equivalent Ga3+ atoms. In the tenth Te2- site, Te2- is bonded in a 4-coordinate geometry to one Na1+, one Ag1+, and two Ga3+ atoms. In the eleventh Te2- site, Te2- is bonded in a 2-coordinate geometry to two equivalent Ag1+ and two equivalent Ga3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TeAsXeO2F11 by Materials Project

XeAsTeO2F11 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two XeAsTeO2F11 clusters. Xe is bonded in a linear geometry to one O and one F atom. The Xe–O bond length is 2.08 Å. The Xe–F bond length is 2.32 Å. As is bonded in an octahedral geometry to six F atoms. There are a spread of As–F bond distances ranging from 1.74–1.94 Å. Te is bonded in an octahedral geometry to two O and four F atoms. There is one shorter (1.97 Å) and one longer (2.01 Å) Te–O bond length. There is two shorter (1.87 Å) and two longer (1.89 Å) Te–F bond length. There are two inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to one Xe and one Te atom. In the second O site, O is bonded in a water-like geometry to one Te and one F atom. The O–F bond length is 1.44 Å. There are eleven inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one O atom. In the second F site, F is bonded in a single-bond geometry to one Te atom. In the third F site, F is bonded in a single-bond geometry to one Te atom. In the fourth F site, F is bonded in a single-bond geometry to one Te atom. In the fifth F site, F is bonded in a single-bond geometry to one Te atom. In the sixth F site, F is bonded in a single-bond geometry to one As atom. In the seventh F site, F is bonded in a single-bond geometry to one As atom. In the eighth F site, F is bonded in a single-bond geometry to one As atom. In the ninth F site, F is bonded in a single-bond geometry to one As atom. In the tenth F site, F is bonded in a single-bond geometry to one As atom. In the eleventh F site, F is bonded in a distorted bent 120 degrees geometry to one Xe and one As atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on DyErTe2 by Materials Project

ErDyTe2 is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Er is bonded to six Te atoms to form ErTe6 octahedra that share corners with six equivalent ErTe6 octahedra, edges with four equivalent ErTe6 octahedra, and edges with eight equivalent DyTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (3.06 Å) and two longer (3.08 Å) Er–Te bond lengths. Dy is bonded to six Te atoms to form DyTe6 octahedra that share corners with six equivalent DyTe6 octahedra, edges with four equivalent DyTe6 octahedra, and edges with eight equivalent ErTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (3.06 Å) and two longer (3.08 Å) Dy–Te bond lengths. There are two inequivalent Te sites. In the first Te site, Te is bonded to four equivalent Er and two equivalent Dy atoms to form a mixture of edge and corner-sharing TeDy2Er4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second Te site, Te is bonded to two equivalent Er and four equivalent Dy atoms to form TeDy4Er2 octahedra that share corners with six equivalent TeDy4Er2 octahedra and edges with twelve TeDy2Er4 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ag3Te(PO7)2 by Materials Project

Ag3Te(PO7)2 crystallizes in the trigonal P312 space group. The structure is three-dimensional. there are two inequivalent Ag sites. In the first Ag site, Ag is bonded to six O atoms to form distorted AgO6 octahedra that share corners with two equivalent TeO6 octahedra, corners with four PO4 tetrahedra, and edges with two equivalent AgO6 octahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Ag–O bond distances ranging from 2.16–2.42 Å. In the second Ag site, Ag is bonded to six O atoms to form distorted AgO6 octahedra that share corners with two equivalent TeO6 octahedra, corners with four PO4 tetrahedra, and edges with two equivalent AgO6 octahedra. The corner-sharing octahedral tilt angles are 52°. There are a spread of Ag–O bond distances ranging from 2.15–2.42 Å. There are two inequivalent P sites. In the first P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with six AgO6 octahedra. The corner-sharing octahedra tilt angles range from 52–55°. There is three shorter (1.54 Å) and one longer (1.58 Å) P–O bond length. In the second P site, P is bonded to four O atoms to form PO4 tetrahedra that share corners with six AgO6 octahedra. The corner-sharing octahedra tilt angles range from 52–55°. There is three shorter (1.54 Å) and one longer (1.58 Å) P–O bond length. There are two inequivalent Te sites. In the first Te site, Te is bonded to six equivalent O atoms to form distorted TeO6 octahedra that share corners with six equivalent AgO6 octahedra. The corner-sharing octahedral tilt angles are 52°. All Te–O bond lengths are 1.95 Å. In the second Te site, Te is bonded to six equivalent O atoms to form distorted TeO6 octahedra that share corners with six equivalent AgO6 octahedra. The corner-sharing octahedral tilt angles are 52°. All Te–O bond lengths are 1.96 Å. There are six inequivalent O sites. In the first O site, O is bonded in a distorted rectangular see-saw-like geometry to three equivalent Ag and one P atom. In the second O site, O is bonded in a distorted rectangular see-saw-like geometry to three equivalent Ag and one P atom. In the third O site, O is bonded in a bent 120 degrees geometry to one Ag and one Te atom. In the fourth O site, O is bonded in a bent 120 degrees geometry to one Ag and one Te atom. In the fifth O site, O is bonded in a bent 120 degrees geometry to one Ag and one P atom. In the sixth O site, O is bonded in a bent 120 degrees geometry to one Ag and one P atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThUTe2 by Materials Project

UThTe2 is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. U is bonded to six Te atoms to form UTe6 octahedra that share corners with six equivalent UTe6 octahedra, edges with four equivalent UTe6 octahedra, and edges with eight equivalent ThTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (3.12 Å) and two longer (3.13 Å) U–Te bond lengths. Th is bonded to six Te atoms to form ThTe6 octahedra that share corners with six equivalent ThTe6 octahedra, edges with four equivalent ThTe6 octahedra, and edges with eight equivalent UTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (3.12 Å) and two longer (3.13 Å) Th–Te bond lengths. There are two inequivalent Te sites. In the first Te site, Te is bonded to four equivalent U and two equivalent Th atoms to form a mixture of edge and corner-sharing TeTh2U4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second Te site, Te is bonded to two equivalent U and four equivalent Th atoms to form TeTh4U2 octahedra that share corners with six equivalent TeTh4U2 octahedra and edges with twelve TeTh2U4 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta4Fe5Te12 by Materials Project

Ta4Fe5Te12 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are four inequivalent Ta+3.50+ sites. In the first Ta+3.50+ site, Ta+3.50+ is bonded to six Te2- atoms to form distorted TaTe6 octahedra that share a cornercorner with one FeTe4 tetrahedra, edges with four TaTe6 octahedra, and edges with two equivalent FeTe4 tetrahedra. There are a spread of Ta–Te bond distances ranging from 2.76–2.92 Å. In the second Ta+3.50+ site, Ta+3.50+ is bonded to six Te2- atoms to form distorted edge-sharing TaTe6 octahedra. There are a spread of Ta–Te bond distances ranging from 2.78–2.94 Å. In the third Ta+3.50+ site, Ta+3.50+ is bonded to six Te2- atoms to form distorted edge-sharing TaTe6 octahedra. There are a spread of Ta–Te bond distances ranging from 2.77–2.91 Å. In the fourth Ta+3.50+ site, Ta+3.50+ is bonded to six Te2- atoms to form distorted TaTe6 octahedra that share a cornercorner with one FeTe4 tetrahedra, edges with four TaTe6 octahedra, and edges with two equivalent FeTe4 tetrahedra. There are a spread of Ta–Te bond distances ranging from 2.76–2.94 Å. There are five inequivalent Fe2+ sites. In the first Fe2+ site, Fe2+ is bonded to four Te2- atoms to form distorted FeTe4 tetrahedra that share a cornercorner with one TaTe6 octahedra, corners with two equivalent FeTe4 tetrahedra, edges with two equivalent TaTe6 octahedra, and edges with two equivalent FeTe4 tetrahedra. The corner-sharing octahedral tilt angles are 78°. All Fe–Te bond lengths are 2.60 Å. In the second Fe2+ site, Fe2+ is bonded in a 6-coordinate geometry to two equivalent Fe2+ and four Te2- atoms. Both Fe–Fe bond lengths are 2.43 Å. There are a spread of Fe–Te bond distances ranging from 2.65–2.79 Å. In the third Fe2+ site, Fe2+ is bonded in a 4-coordinate geometry to four Te2- atoms. There are a spread of Fe–Te bond distances ranging from 2.61–2.71 Å. In the fourth Fe2+ site, Fe2+ is bonded to four Te2- atoms to form distorted FeTe4 tetrahedra that share a cornercorner with one TaTe6 octahedra, corners with two equivalent FeTe4 tetrahedra, edges with two equivalent TaTe6 octahedra, and edges with two equivalent FeTe4 tetrahedra. The corner-sharing octahedral tilt angles are 79°. There are one shorter (2.59 Å) and three longer (2.60 Å) Fe–Te bond lengths. In the fifth Fe2+ site, Fe2+ is bonded in a 7-coordinate geometry to two equivalent Fe2+ and five Te2- atoms. There are a spread of Fe–Te bond distances ranging from 2.74–2.98 Å. There are twelve inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to two equivalent Ta+3.50+ and one Fe2+ atom. In the second Te2- site, Te2- is bonded in a 5-coordinate geometry to two equivalent Ta+3.50+ and three Fe2+ atoms. In the third Te2- site, Te2- is bonded in a 4-coordinate geometry to two equivalent Ta+3.50+ and two Fe2+ atoms. In the fourth Te2- site, Te2- is bonded in a 3-coordinate geometry to two equivalent Ta+3.50+ and one Fe2+ atom. In the fifth Te2- site, Te2- is bonded in a 4-coordinate geometry to one Ta+3.50+ and three Fe2+ atoms. In the sixth Te2- site, Te2- is bonded in a 4-coordinate geometry to one Ta+3.50+ and three Fe2+ atoms. In the seventh Te2- site, Te2- is bonded in a 6-coordinate geometry to one Ta+3.50+ and five Fe2+ atoms. In the eighth Te2- site, Te2- is bonded in a 4-coordinate geometry to one Ta+3.50+ and three Fe2+ atoms. In the ninth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ta+3.50+ atoms. In the tenth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ta+3.50+ atoms. In the eleventh Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ta+3.50+ atoms. In the twelfth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ta+3.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaTeO3 by Materials Project

CaTeO3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are nine inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.84 Å. In the second Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.80 Å. In the third Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted edge-sharing CaO7 pentagonal bipyramids. There are a spread of Ca–O bond distances ranging from 2.33–2.64 Å. In the fourth Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 hexagonal pyramids that share a cornercorner with one CaO6 pentagonal pyramid, an edgeedge with one CaO7 hexagonal pyramid, and an edgeedge with one CaO7 pentagonal bipyramid. There are a spread of Ca–O bond distances ranging from 2.44–2.57 Å. In the fifth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.38–2.71 Å. In the sixth Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted edge-sharing CaO7 pentagonal bipyramids. There are a spread of Ca–O bond distances ranging from 2.35–2.71 Å. In the seventh Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.89 Å. In the eighth Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted corner-sharing CaO6 pentagonal pyramids. There are a spread of Ca–O bond distances ranging from 2.24–2.58 Å. In the ninth Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.32–3.02 Å. There are nine inequivalent Te4+ sites. In the first Te4+ site, Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.87–1.92 Å. In the second Te4+ site, Te4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.88 Å) and one longer (1.89 Å) Te–O bond length. In the third Te4+ site, Te4+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.88–1.90 Å. In the fourth Te4+ site, Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There is one shorter (1.89 Å) and two longer (1.91 Å) Te–O bond length. In the fifth Te4+ site, Te4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.87 Å) and two longer (1.89 Å) Te–O bond length. In the sixth Te4+ site, Te4+ is bonded in a 3-coordinate geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.89–2.80 Å. In the seventh Te4+ site, Te4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.88 Å) and two longer (1.90 Å) Te–O bond length. In the eighth Te4+ site, Te4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.87–1.90 Å. In the ninth Te4+ site, Te4+ is bonded in a 3-coordinate geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.90–2.56 Å. There are twenty-seven inequivalent O2- sites. In the first O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te trigonal pyramids. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ca2+ and one Te4+ atom. In the third O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+ and one Te4+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to two Ca2+ and one Te4+ atom. In the sixth O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te tetrahedra. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Te4+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to two Ca2+ and one Te4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Te4+ atom. In the tenth O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of corner and edge-sharing OCa3Te tetrahedra. In the eleventh O2- site, O2- is bonded in a trigonal planar geometry to two Ca2+ and one Te4+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one Ca2+ and one Te4+ atom. In the thirteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Ca2+ and one Te4+ atom. In the fourteenth O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te tetrahedra. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Te4+ atom. In the sixteenth O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te trigonal pyramids. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to three Ca2+ and one Te4+ atom. In the eighteenth O2- site, O2- is bonded in a 2-coordinate geometry to three Ca2+ and one Te4+ atom. In the nineteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Ca2+ and one Te4+ atom. In the twentieth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ca2+ and one Te4+ atom. In the twenty-first O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te tetrahedra. In the twenty-second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Ca2+ and two Te4+ atoms. In the twenty-third O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te tetrahedra. In the twenty-fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ca2+ and one Te4+ atom. In the twenty-fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Te4+ atom. In the twenty-sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Te4+ atoms. In the twenty-seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two Ca2+ and one Te4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg16Al12Te by Materials Project

Mg16Al12Te crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are five inequivalent Mg sites. In the first Mg site, Mg is bonded in a 4-coordinate geometry to six Mg, five Al, and one Te atom. There are a spread of Mg–Mg bond distances ranging from 3.12–3.17 Å. There are a spread of Mg–Al bond distances ranging from 2.91–3.35 Å. The Mg–Te bond length is 2.95 Å. In the second Mg site, Mg is bonded in a 3-coordinate geometry to seven Mg, five Al, and one Te atom. There are a spread of Mg–Mg bond distances ranging from 3.07–3.18 Å. There are a spread of Mg–Al bond distances ranging from 3.02–3.16 Å. The Mg–Te bond length is 3.46 Å. In the third Mg site, Mg is bonded in a 1-coordinate geometry to three equivalent Mg, twelve Al, and one Te atom. All Mg–Mg bond lengths are 3.21 Å. There are a spread of Mg–Al bond distances ranging from 3.17–3.31 Å. The Mg–Te bond length is 3.27 Å. In the fourth Mg site, Mg is bonded in a 10-coordinate geometry to four Mg and six Al atoms. Both Mg–Mg bond lengths are 3.08 Å. There are a spread of Mg–Al bond distances ranging from 3.07–3.12 Å. In the fifth Mg site, Mg is bonded in a 12-coordinate geometry to seven Mg and five Al atoms. Both Mg–Mg bond lengths are 3.28 Å. There are a spread of Mg–Al bond distances ranging from 2.89–3.19 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 11-coordinate geometry to eight Mg and three Al atoms. There are one shorter (2.67 Å) and two longer (2.81 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a 11-coordinate geometry to eight Mg and three Al atoms. Both Al–Al bond lengths are 2.73 Å. In the third Al site, Al is bonded in a 11-coordinate geometry to seven Mg, three Al, and one Te atom. There are one shorter (2.77 Å) and one longer (2.78 Å) Al–Al bond lengths. The Al–Te bond length is 3.27 Å. Te is bonded in a 4-coordinate geometry to seven Mg and six equivalent Al atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Parameter extraction approaches for compact modeling of thermoelectric modules

Thermoelectric (TE) cooling has experienced rapid advancements with the foundational understanding of TE materials. TE modules, compact and lightweight devices, have become the prevalent approach for implementing TE technologies. Accurately quantifying TE physical parameters (Seebeck coefficient α, thermal conductivity κ, and thermal resistance ρ) is challenging due to the dynamic temperature changes in operation. Furthermore, extracting lumped property parameters is crucial for designing energy systems using TE modules. Existing research has several limitations, such as lack of comparative analysis between prevalent formulae, reliance on potentially inaccurate vendor-supplied data, disregard for fundamental assumptions, and absence of empirical measurements. Further, this study addresses these gaps by conducting TE material characterization, comparing three existing formulae using vendor datasheets, designing a laboratory test facility for model validation and refinement, and outlining a structured data extraction procedure. The study's novelty lies in multiple key contributions: (1) a detailed comparative analysis of existing formulae for extracting TE property parameter; (2) executing experimental work in a laboratory setting to validate the model and elucidate its limitations; (3) highlighting potential risks; (4) clarifying possible assumptions from both material and engineering perspectives; and (5) considering temperature differential impacts. This comprehensive approach addresses the current research gaps and provides valuable insights into the design and application of TE modules in various energy systems.

36 MATERIALS SCIENCE↗
NASA NTRS1994

Variability of dayside electron temperature at Venus

Langmuir probe measurements on Pioneer Venus Orbiter show that electron temperature (Te) profiles exhibit two distinct regions. The lower, but more extended region is in the main ionosphere where Te increases slowly with altitude. The other, less extended region is in the ionopause, where Te rise sharply with altitude. If horizontal magnetic fields and flux ropes in the ionosphere inhibit vertical thermal conductivity sufficiently, then the observed Te profile could be explained with EUV as the major heat source (Cravens et al., 1980). The rise in Te in the ionopause region has generally been attributed to solar wind heating (Brace and Kliore, 1991). We suggest that this sharp rise in Te is due primarily to the steep fall in electron density, Ne. If the heating rate is essentially unchanged and heat conduction is not of primary importance, then a steep rise in Te will maintain a constant electron cooling rate for a steeply falling Ne. We have observed large orbit to orbit variations in Te in the ionopause region which are found to be inversely related to changes in Ne. Variations in solar wind dynamic pressure do not seem to have a direct effect on Te, rather the effect is indirect coming through the sharp decrease in Ne.

Mahajan, K. K.↗
NASA NTRS2001

Band Anticrossing in Highly Mismatched Compound Semiconductor Alloys

Compound semiconductor alloys in which metallic anions are partially replaced with more electronegative isoelectronic atoms have recently attracted significant attention. Group IIIN(x)V(1-x), alloys with a small amount of the electronegative N substituting more metallic column V elements has been the most extensively studied class of such Highly Mismatched Alloys (HMAs). We have shown that many of the unusual properties of the IIIN(x),V(1-x) alloys can be well explained by the Band Anticrossing (BAC) model that describes the electronic structure in terms of an interaction between highly localized levels of substitutional N and the extended states of the host semiconductor matrix. Most recently the BAC model has been also used to explain similar modifications of the electronic band structure observed in Te-rich ZnS(x)Te(l-x) and ZnSe(Y)Te(1-y) alloys. To date studies of HMAs have been limited to materials with relatively small concentrations of highly electronegative atoms. Here we report investigations of the electronic structure of ZnSe(y)Te(1-y) alloys in the entire composition range, 0 less than or equal to y less than or equal to 1. The samples used in this study are bulk ZnSe(y)Te(1-y) crystals grown by either a modified Bridgman method or by physical vapor transport. Photomodulated reflection (PR) spectroscopy was used to measure the composition dependence of optical transitions from the valence band edge and from the spin-orbit split off band to the conduction band. The pressure dependence of the band gap was measured using optical absorption in a diamond anvil cell. We find that the energy of the spin-orbit split off valence band edge does not depend on composition and is located at about 3 eV below the conduction band edge of ZnSe. On the Te-rich side the pressure and the composition dependence of the optical transitions are well explained by the BAC model which describes the downward shift of the conduction band edge in terms of the interaction between localized Se states and the conduction band. On the other hand we show that the large band gap reduction observed on the Se-rich side of the alloy system is a result of an interaction between the localized Te level and the valence bands. This interaction leads to the formation of a Te-like valence band edge that strongly interacts with the light hole valence band. Calculations based on a modified k p model account for the reduction of the band gap and the large increase of the spin-orbit splitting observed in Se-rich ZnSe(y)Te(l-y) alloys. We will also discuss the importance of these new results for understanding of the electronic structure and band offsets in other highly mismatched alloy systems.

Yu, Kin Man↗
NASA NTRS2001

Band Anticrossing in Highly Mismatched Compound Semiconductor Alloys

Compound semiconductor alloys in which metallic anions are partially replaced with more electronegative isoelectronic atoms have recently attracted significant attention. Group IIIN(sub x)V(sub 1-x) alloys with a small amount of the electronegative N substituting more metallic column V elements has been the most extensively studied class of such Highly Mismatched Alloys (HMAs). We have shown that many of the unusual properties of the IIIN(sub x)V(sub 1-x) alloys can be well explained by the Band Anticrossing (BAC) model that describes the electronic structure in terms of an interaction between highly localized levels of substitutional N and the extended states of the host semiconductor matrix. Most recently the BAC model has been also used to explain similar modifications of the electronic band structure observed in Te-rich ZnS(sub x)Te(sub 1-x) and ZnSe(sub y)Te(sub 1-y) alloys. To date studies of HMAs have been limited to materials with relatively small concentrations of highly electronegative atoms. Here we report investigations of the electronic structure of ZnSe(sub y)Te(sub 1-y) alloys in the entire composition range, y between 0 and 1. The samples used in this study are bulk ZnSe(sub y)Te(sub 1-y) crystals grown by either a modified Bridgman method or by physical vapor transport. Photomodulated reflection (PR) spectroscopy was used to measure the composition dependence of optical transitions from the valence band edge and from the spin-orbit split off band to the conduction band. The pressure dependence of the band gap was measured using optical absorption in a diamond anvil cell. We find that the energy of the spin-orbit split off valence band edge does not depend on composition and is located at about 3 eV below the conduction band edge of ZnSe. On the Te-rich side the pressure and the composition dependence of the optical transitions are well explained by the BAC model which describes the downward shift of the conduction band edge in terms of the interaction between localized Se states and the conduction band. On the other hand we show that the large band gap reduction observed on the Se-rich side of the alloy system is a result of an interaction between the localized Te level and the valence bands. This interaction leads to the formation of a Te-like valence band edge that strongly interacts with the light hole valence band. Calculations based on a modified k(sup dot)p model account for the reduction of the band gap and the large increase of the spin-orbit splitting observed in Se-rich ZnSe(sub y)Te(sub 1-y) alloys. We will also discuss the importance of these new results for understanding of the electronic structure and band offsets in other highly mismatched alloy systems.

Yu, Kin Man↗