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DOE OSTI2020

Materials Data on TaOF3 by Materials Project

TaOF3 crystallizes in the triclinic P1 space group. The structure is two-dimensional and consists of one TaOF3 sheet oriented in the (0, 1, 2) direction. there are five inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to two equivalent O2- and four F1- atoms to form distorted corner-sharing TaO2F4 octahedra. The corner-sharing octahedra tilt angles range from 1–8°. There are one shorter (1.80 Å) and one longer (2.27 Å) Ta–O bond lengths. There is two shorter (1.90 Å) and two longer (2.06 Å) Ta–F bond length. In the second Ta5+ site, Ta5+ is bonded to one O2- and five F1- atoms to form corner-sharing TaOF5 octahedra. The corner-sharing octahedra tilt angles range from 8–9°. The Ta–O bond length is 1.74 Å. There are a spread of Ta–F bond distances ranging from 2.00–2.06 Å. In the third Ta5+ site, Ta5+ is bonded to one O2- and five F1- atoms to form corner-sharing TaOF5 octahedra. The corner-sharing octahedral tilt angles are 8°. The Ta–O bond length is 1.74 Å. There are a spread of Ta–F bond distances ranging from 2.00–2.05 Å. In the fourth Ta5+ site, Ta5+ is bonded to one O2- and five F1- atoms to form corner-sharing TaOF5 octahedra. The corner-sharing octahedral tilt angles are 8°. The Ta–O bond length is 1.74 Å. There are a spread of Ta–F bond distances ranging from 2.00–2.05 Å. In the fifth Ta5+ site, Ta5+ is bonded to one O2- and five F1- atoms to form corner-sharing TaOF5 octahedra. The corner-sharing octahedra tilt angles range from 6–8°. The Ta–O bond length is 1.75 Å. There are a spread of Ta–F bond distances ranging from 2.00–2.05 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Ta5+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one Ta5+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one Ta5+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Ta5+ atom. In the fifth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Ta5+ atoms. There are fifteen inequivalent F1- sites. In the first F1- site, F1- is bonded in a linear geometry to two Ta5+ atoms. In the second F1- site, F1- is bonded in a linear geometry to two Ta5+ atoms. In the third F1- site, F1- is bonded in a linear geometry to two Ta5+ atoms. In the fourth F1- site, F1- is bonded in a single-bond geometry to one Ta5+ atom. In the fifth F1- site, F1- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the sixth F1- site, F1- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the seventh F1- site, F1- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the eighth F1- site, F1- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the ninth F1- site, F1- is bonded in a single-bond geometry to one Ta5+ atom. In the tenth F1- site, F1- is bonded in a single-bond geometry to one Ta5+ atom. In the eleventh F1- site, F1- is bonded in a single-bond geometry to one Ta5+ atom. In the twelfth F1- site, F1- is bonded in a single-bond geometry to one Ta5+ atom. In the thirteenth F1- site, F1- is bonded in a single-bond geometry to one Ta5+ atom. In the fourteenth F1- site, F1- is bonded in a linear geometry to two Ta5+ atoms. In the fifteenth F1- site, F1- is bonded in a linear geometry to two Ta5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3Ta8O21 by Materials Project

K3Ta8O21 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to twelve O2- atoms. There are a spread of K–O bond distances ranging from 2.91–3.28 Å. There are two inequivalent Ta+4.88+ sites. In the first Ta+4.88+ site, Ta+4.88+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 21–41°. There are three shorter (1.93 Å) and three longer (2.11 Å) Ta–O bond lengths. In the second Ta+4.88+ site, Ta+4.88+ is bonded to six equivalent O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 37°. All Ta–O bond lengths are 2.00 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one K1+ and three equivalent Ta+4.88+ atoms. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent K1+ and two equivalent Ta+4.88+ atoms. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent K1+ and two Ta+4.88+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li3Ta5Cu2O15 by Materials Project

Li3Ta5Cu2O15 is pyrite-derived structured and crystallizes in the trigonal R3 space group. The structure is three-dimensional. there are six inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.09 Å) and three longer (2.35 Å) Li–O bond lengths. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.06 Å) and three longer (2.32 Å) Li–O bond lengths. In the third Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.08 Å) and three longer (2.38 Å) Li–O bond lengths. In the fourth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.06 Å) and three longer (2.32 Å) Li–O bond lengths. In the fifth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.05 Å) and three longer (2.35 Å) Li–O bond lengths. In the sixth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.06 Å) and three longer (2.32 Å) Li–O bond lengths. There are ten inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 35–38°. There are three shorter (1.96 Å) and three longer (2.07 Å) Ta–O bond lengths. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 35–38°. There are three shorter (1.96 Å) and three longer (2.07 Å) Ta–O bond lengths. In the third Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 36–38°. There are three shorter (1.94 Å) and three longer (2.10 Å) Ta–O bond lengths. In the fourth Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 35–38°. There are three shorter (1.93 Å) and three longer (2.10 Å) Ta–O bond lengths. In the fifth Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 36–37°. There are three shorter (1.95 Å) and three longer (2.06 Å) Ta–O bond lengths. In the sixth Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 36–38°. There are three shorter (1.94 Å) and three longer (2.07 Å) Ta–O bond lengths. In the seventh Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 35–38°. There are three shorter (1.94 Å) and three longer (2.10 Å) Ta–O bond lengths. In the eighth Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 35–38°. There are three shorter (1.93 Å) and three longer (2.10 Å) Ta–O bond lengths. In the ninth Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 36–37°. There are three shorter (1.96 Å) and three longer (2.07 Å) Ta–O bond lengths. In the tenth Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 35–38°. There are three shorter (1.95 Å) and three longer (2.07 Å) Ta–O bond lengths. There are four inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded in a distorted trigonal planar geometry to three equivalent O2- atoms. All Cu–O bond lengths are 2.03 Å. In the second Cu1+ site, Cu1+ is bonded in a distorted trigonal planar geometry to three equivalent O2- atoms. All Cu–O bond lengths are 2.03 Å. In the third Cu1+ site, Cu1+ is bonded in a distorted trigonal planar geometry to three equivalent O2- atoms. All Cu–O bond lengths are 2.03 Å. In the fourth Cu1+ site, Cu1+ is bonded in a distorted trigonal planar geometry to three equivalent O2- atoms. All Cu–O bond lengths are 2.03 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Ta5+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+ and two Ta5+ atoms. In the third O2- site, O2- is bonded to one Li1+, two Ta5+, and one Cu1+ atom to form a mixture of distorted edge and corner-sharing OLiTa2Cu tetrahedra. In the fourth O2- site, O2- is bonded to one Li1+, two Ta5+, and one Cu1+ atom to form a mixture of distorted edge and corner-sharing OLiTa2Cu tetrahedra. In the fifth O2- site, O2- is bonded to one Li1+, two Ta5+, and one Cu1+ atom to form a mixture of distorted edge and corner-sharing OLiTa2Cu tetrahedra. In the sixth O2- site, O2- is bonded to one Li1+, two Ta5+, and one Cu1+ atom to form a mixture of distorted edge and corner-sharing OLiTa2Cu tetrahedra. In the seventh O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Ta5+ atoms. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+ and two Ta5+ atoms. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+ and two Ta5+ atoms. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+ and two Ta5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta4Fe2N by Materials Project

Ta4Fe2N crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. there are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a 12-coordinate geometry to six equivalent Fe atoms. All Ta–Fe bond lengths are 2.55 Å. In the second Ta site, Ta is bonded in a distorted bent 150 degrees geometry to two equivalent Fe and two equivalent N atoms. Both Ta–Fe bond lengths are 2.68 Å. Both Ta–N bond lengths are 2.18 Å. Fe is bonded in a 12-coordinate geometry to six Ta atoms. N is bonded to six equivalent Ta atoms to form corner-sharing NTa6 octahedra. The corner-sharing octahedral tilt angles are 39°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta4Ni2N by Materials Project

Ta4Ni2N crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. there are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a distorted hexagonal planar geometry to six equivalent Ni atoms. All Ta–Ni bond lengths are 2.50 Å. In the second Ta site, Ta is bonded in a distorted bent 150 degrees geometry to four equivalent Ni and two equivalent N atoms. There are two shorter (2.78 Å) and two longer (3.04 Å) Ta–Ni bond lengths. Both Ta–N bond lengths are 2.17 Å. Ni is bonded in a 12-coordinate geometry to nine Ta and three equivalent Ni atoms. All Ni–Ni bond lengths are 2.66 Å. N is bonded to six equivalent Ta atoms to form corner-sharing NTa6 octahedra. The corner-sharing octahedral tilt angles are 37°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta2N3 by Materials Project

Ta2N3 is Stibnite structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Ta+4.50+ sites. In the first Ta+4.50+ site, Ta+4.50+ is bonded to seven N3- atoms to form a mixture of distorted edge and corner-sharing TaN7 pentagonal bipyramids. There are a spread of Ta–N bond distances ranging from 2.12–2.21 Å. In the second Ta+4.50+ site, Ta+4.50+ is bonded in a 7-coordinate geometry to eight N3- atoms. There are a spread of Ta–N bond distances ranging from 2.18–2.60 Å. There are three inequivalent N3- sites. In the first N3- site, N3- is bonded to five Ta+4.50+ atoms to form a mixture of distorted edge and corner-sharing NTa5 trigonal bipyramids. In the second N3- site, N3- is bonded to five Ta+4.50+ atoms to form a mixture of distorted edge and corner-sharing NTa5 square pyramids. In the third N3- site, N3- is bonded in a 4-coordinate geometry to five Ta+4.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on U2Ta3Ge4 by Materials Project

U2Ta3Ge4 is Magnesium tetraboride-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. U is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of U–Ge bond distances ranging from 2.74–2.94 Å. There are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a 5-coordinate geometry to six Ge atoms. There are a spread of Ta–Ge bond distances ranging from 2.63–3.17 Å. In the second Ta site, Ta is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Ta–Ge bond distances ranging from 2.71–2.96 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to two equivalent U, six Ta, and one Ge atom. The Ge–Ge bond length is 2.64 Å. In the second Ge site, Ge is bonded in a 7-coordinate geometry to three equivalent U and four Ta atoms. In the third Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent U, four Ta, and one Ge atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta4Co2C by Materials Project

Ta4Co2C crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. there are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a 6-coordinate geometry to six equivalent Co atoms. All Ta–Co bond lengths are 2.51 Å. In the second Ta site, Ta is bonded in a distorted bent 150 degrees geometry to four equivalent Co and two equivalent C atoms. There are two shorter (2.78 Å) and two longer (3.00 Å) Ta–Co bond lengths. Both Ta–C bond lengths are 2.18 Å. Co is bonded in a 12-coordinate geometry to nine Ta and three equivalent Co atoms. All Co–Co bond lengths are 2.70 Å. C is bonded to six equivalent Ta atoms to form corner-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 39°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on U2Ta3Ge4 by Materials Project

U2Ta3Ge4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. U is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of U–Ge bond distances ranging from 2.86–3.01 Å. There are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Ta–Ge bond distances ranging from 2.62–2.78 Å. In the second Ta site, Ta is bonded to six Ge atoms to form distorted corner-sharing TaGe6 octahedra. The corner-sharing octahedra tilt angles range from 46–53°. There are a spread of Ta–Ge bond distances ranging from 2.74–2.83 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent U, four Ta, and one Ge atom. The Ge–Ge bond length is 2.68 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to four equivalent U, four Ta, and one Ge atom. The Ge–Ge bond length is 2.79 Å. In the third Ge site, Ge is bonded in a 9-coordinate geometry to two equivalent U, six Ta, and one Ge atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta4WC5 by Materials Project

Ta4WC5 is Caswellsilverite-like structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Ta+4.50+ sites. In the first Ta+4.50+ site, Ta+4.50+ is bonded to six C4- atoms to form TaC6 octahedra that share corners with three equivalent TaC6 octahedra, corners with three equivalent WC6 octahedra, edges with three equivalent WC6 octahedra, and edges with nine TaC6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are three shorter (2.23 Å) and three longer (2.25 Å) Ta–C bond lengths. In the second Ta+4.50+ site, Ta+4.50+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.24 Å. W2+ is bonded to six equivalent C4- atoms to form WC6 octahedra that share corners with six equivalent TaC6 octahedra, edges with six equivalent TaC6 octahedra, and edges with six equivalent WC6 octahedra. The corner-sharing octahedral tilt angles are 2°. All W–C bond lengths are 2.21 Å. There are three inequivalent C4- sites. In the first C4- site, C4- is bonded to six Ta+4.50+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second C4- site, C4- is bonded to six equivalent Ta+4.50+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third C4- site, C4- is bonded to three equivalent Ta+4.50+ and three equivalent W2+ atoms to form a mixture of corner and edge-sharing CTa3W3 octahedra. The corner-sharing octahedra tilt angles range from 0–1°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta4Co2N by Materials Project

Ta4Co2N crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. there are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a distorted hexagonal planar geometry to six equivalent Co atoms. All Ta–Co bond lengths are 2.49 Å. In the second Ta site, Ta is bonded in a distorted bent 150 degrees geometry to four equivalent Co and two equivalent N atoms. There are two shorter (2.79 Å) and two longer (3.00 Å) Ta–Co bond lengths. Both Ta–N bond lengths are 2.17 Å. Co is bonded in a 12-coordinate geometry to nine Ta and three equivalent Co atoms. All Co–Co bond lengths are 2.63 Å. N is bonded to six equivalent Ta atoms to form corner-sharing NTa6 octahedra. The corner-sharing octahedral tilt angles are 39°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K9Ta2VS12 by Materials Project

K9Ta2VS12 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are thirty-one inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.26–3.79 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.25–3.78 Å. In the third K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.25–3.79 Å. In the fourth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.14–3.79 Å. In the fifth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.16–3.79 Å. In the sixth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.24–3.78 Å. In the seventh K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.15–3.88 Å. In the eighth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.15–3.79 Å. In the ninth K1+ site, K1+ is bonded in a 5-coordinate geometry to five S2- atoms. There are a spread of K–S bond distances ranging from 3.15–3.43 Å. In the tenth K1+ site, K1+ is bonded in a 5-coordinate geometry to five S2- atoms. There are a spread of K–S bond distances ranging from 3.15–3.43 Å. In the eleventh K1+ site, K1+ is bonded in a 5-coordinate geometry to five S2- atoms. There are a spread of K–S bond distances ranging from 3.15–3.43 Å. In the twelfth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.25–3.59 Å. In the thirteenth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.25–3.59 Å. In the fourteenth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.25–3.59 Å. In the fifteenth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.25–3.59 Å. In the sixteenth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.24–3.59 Å. In the seventeenth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.24–3.59 Å. In the eighteenth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.22–3.55 Å. In the nineteenth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.22–3.55 Å. In the twentieth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.22–3.55 Å. In the twenty-first K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.23–3.59 Å. In the twenty-second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.22–3.55 Å. In the twenty-third K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.23–3.59 Å. In the twenty-fourth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.22–3.55 Å. In the twenty-fifth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.22–3.55 Å. In the twenty-sixth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.23–3.59 Å. In the twenty-seventh K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.23–3.59 Å. In the twenty-eighth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.25–3.59 Å. In the twenty-ninth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.25–3.59 Å. In the thirtieth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.24–3.59 Å. In the thirty-first K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.24–3.59 Å. There are seven inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded in a tetrahedral geometry to four S2- atoms. There are two shorter (2.28 Å) and two longer (2.29 Å) Ta–S bond lengths. In the second Ta5+ site, Ta5+ is bonded in a tetrahedral geometry to four S2- atoms. There are two shorter (2.28 Å) and two longer (2.29 Å) Ta–S bond lengths. In the third Ta5+ site, Ta5+ is bonded in a tetrahedral geometry to four S2- atoms. There are two shorter (2.28 Å) and two longer (2.29 Å) Ta–S bond lengths. In the fourth Ta5+ site, Ta5+ is bonded in a tetrahedral geometry to four S2- atoms. There are two shorter (2.28 Å) and two longer (2.29 Å) Ta–S bond lengths. In the fifth Ta5+ site, Ta5+ is bonded in a tetrahedral geometry to four S2- atoms. There are two shorter (2.28 Å) and two longer (2.29 Å) Ta–S bond lengths. In the sixth Ta5+ site, Ta5+ is bonded in a tetrahedral geometry to four S2- atoms. There are two shorter (2.28 Å) and two longer (2.29 Å) Ta–S bond lengths. In the seventh Ta5+ site, Ta5+ is bonded in a tetrahedral geometry to four S2- atoms. There are two shorter (2.28 Å) and two longer (2.29 Å) Ta–S bond lengths. There are four inequivalent V5+ sites. In the first V5+ site, V5+ is bonded in a tetrahedral geometry to four S2- atoms. There are two shorter (2.16 Å) and two longer (2.17 Å) V–S bond lengths. In the second V5+ site, V5+ is bonded in a tetrahedral geometry to four S2- atoms. There are two shorter (2.16 Å) and two longer (2.17 Å) V–S bond lengths. In the third V5+ site, V5+ is bonded in a tetrahedral geometry to four S2- atoms. There are two shorter (2.16 Å) and two longer (2.17 Å) V–S bond lengths. In the fourth V5+ site, V5+ is bonded in a tetrahedral geometry to four S2- atoms. There are two shorter (2.16 Å) and two longer (2.17 Å) V–S bond lengths. There are forty-eight inequivalent S2- sites. In the first S2- site, S2- is bonded in a 1-coordinate geometry to four K1+ and one V5+ atom. In the second S2- site, S2- is bonded in a 1-coordinate geometry to four K1+ and one V5+ atom. The S–K bond length is 3.42 Å. In the third S2- site, S2- is bonded in a 1-coordinate geometry to four K1+ and one V5+ atom. In the fourth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. In the fifth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one V5+ atom. The S–K bond length is 3.42 Å. In the sixth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. The S–K bond length is 3.79 Å. In the seventh S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. The S–K bond length is 3.33 Å. In the eighth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. In the ninth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. In the tenth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. The S–Ta bond length is 2.28 Å. In the eleventh S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. There are one shorter (3.33 Å) and one longer (3.41 Å) S–K bond lengths. In the twelfth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. In the thirteenth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. The S–K bond length is 3.42 Å. In the fourteenth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. The S–K bond length is 3.30 Å. In the fifteenth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. In the sixteenth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. There are one shorter (3.30 Å) and one longer (3.42 Å) S–K bond lengths. The S–Ta bond length is 2.28 Å. In the seventeenth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. The S–K bond length is 3.41 Å. In the eighteenth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. In the nineteenth S2- site, S2- is bonded in a 1-coordinate geometry to four K1+ and one V5+ atom. In the twentieth S2- site, S2- is bonded in a 1-coordinate geometry to four K1+ and one V5+ atom. The S–K bond length is 3.28 Å. In the twenty-first S2- site, S2- is bonded in a 1-coordinate geometry to four K1+ and one V5+ atom. The S–K bond length is 3.42 Å. In the twenty-second S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. In the twenty-third S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one V5+ atom. There are a spread of S–K bond distances ranging from 3.28–3.88 Å. In the twenty-fourth S2- site, S2- is bonded in a 1-coordinate geometry to five K1+ and one Ta5+ atom. In the twenty-fifth S2- site, S2- is bonded in a distorted single-bond geometry to six K1+ and one V5+ atom. In the twenty-sixth S2- site, S2- is bonded in a distorted single-bond geometry to six K1+ and one V5+ atom. In the twenty-seventh S2- site, S2- is bonded in a distorted single-bond geometry to six K1+ and one V5+ atom. In the twenty-eighth S2- site, S2- is bonded in a 1-coordinate geometry to six K1+ and one Ta5+ atom. In the twenty-ninth S2- site, S2- is bonded in a distorted single-bond geometry to six K1+ and one V5+ atom. In the thirtieth S2- site, S2- is bonded in a 1-coordinate geometry to six K1+ and one Ta5+ atom. In the thirty-first S2- site, S2- is bonded in a 1-coordinate geometry to six K1+ and one Ta5+ atom. In the thirty-second S2- site, S2- is bonded in a 1-coordinate geometry to six K1+ and one Ta5+ atom. There are one shorter (3.43 Å) and one longer (3.51 Å) S–K bond lengths. In the thirty-third S2- site, S2- is bonded in a 1-coordinate geometry to six K1+ and one Ta5+ atom. The S–K bond length is 3.59 Å. In the thirty-fourth S2- site, S2- is bonded in a 1-coordinate geometry to six K1+ and one Ta5+ atom. The S–K bond length is 3.51 Å. The S–Ta bond length is 2.29 Å. In the thirty-fifth S2- site, S2- is bonded in a 1-coordinate geometry to six K1+ and one Ta5+ atom. There are one shorter (3.31 Å) and one longer (3.59 Å) S–K bond lengths. In the thirty-sixth S2- site, S2- is bonded in a 1-coordinate geometry to six K1+ and one Ta5+ atom. In the thirty-seventh S2- site, S2- is bonded to five K1+ and one V5+ atom to form distorted edge-sharing SK5V octahedra. In the thirty-eighth S2- site, S2- is bonded to five K1+ and one V5+ atom to form distorted edge-sharing SK5V octahedra. In the thirty-ninth S2- site, S2- is bonded to five K1+ and one V5+ atom to form distorted edge-sharing SK5V octahedra. In the fortieth S2- site, S2- is bonded to five K1+ and one Ta5+ atom to form distorted edge-sharing SK5Ta octahedra. In the forty-first S2- site, S2- is bonded to five K1+ and one V5+ atom to form distorted edge-sharing SK5V octahedra. In the forty-second S2- site, S2- is bonded to five K1+ and one Ta5+ atom to form distorted edge-sharing SK5Ta octahedra. In the forty-third S2- site, S2- is bonded to five K1+ and one Ta5+ atom to form disto

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3TaO2F7 by Materials Project

K3TaO2F7 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are three inequivalent K sites. In the first K site, K is bonded in a 6-coordinate geometry to six F atoms. There are a spread of K–F bond distances ranging from 2.60–3.13 Å. In the second K site, K is bonded in a 8-coordinate geometry to one O and seven F atoms. The K–O bond length is 2.97 Å. There are a spread of K–F bond distances ranging from 2.49–3.13 Å. In the third K site, K is bonded in a 6-coordinate geometry to one O and five F atoms. The K–O bond length is 3.02 Å. There are a spread of K–F bond distances ranging from 2.48–2.92 Å. Ta is bonded in a distorted pentagonal bipyramidal geometry to two O and five F atoms. Both Ta–O bond lengths are 2.12 Å. There are a spread of Ta–F bond distances ranging from 1.92–1.96 Å. There are two inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to one K, one Ta, and one O atom. The O–O bond length is 1.37 Å. In the second O site, O is bonded in a 3-coordinate geometry to one K, one Ta, and one O atom. There are seven inequivalent F sites. In the first F site, F is bonded in a distorted single-bond geometry to two K and one Ta atom. In the second F site, F is bonded in a distorted single-bond geometry to two K and one Ta atom. In the third F site, F is bonded in a distorted single-bond geometry to two K and one Ta atom. In the fourth F site, F is bonded in a distorted rectangular see-saw-like geometry to four K atoms. In the fifth F site, F is bonded to four K atoms to form distorted edge-sharing FK4 tetrahedra. In the sixth F site, F is bonded in a distorted trigonal non-coplanar geometry to two K and one Ta atom. In the seventh F site, F is bonded in a distorted single-bond geometry to two K and one Ta atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta3(InSe3)2 by Materials Project

Ta3(InSe3)2 crystallizes in the hexagonal P-6m2 space group. The structure is two-dimensional and consists of one Ta3(InSe3)2 sheet oriented in the (0, 0, 1) direction. there are two inequivalent Ta+3.33+ sites. In the first Ta+3.33+ site, Ta+3.33+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing TaSe6 pentagonal pyramids. All Ta–Se bond lengths are 2.62 Å. In the second Ta+3.33+ site, Ta+3.33+ is bonded to six Se2- atoms to form distorted edge-sharing TaSe6 pentagonal pyramids. There are three shorter (2.61 Å) and three longer (2.63 Å) Ta–Se bond lengths. In1+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are three shorter (3.30 Å) and three longer (3.35 Å) In–Se bond lengths. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Ta+3.33+ and three equivalent In1+ atoms. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to three equivalent Ta+3.33+ and three equivalent In1+ atoms. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Ta+3.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta5Ge3B by Materials Project

Ta5BGe3 crystallizes in the hexagonal P6_3/mcm space group. The structure is three-dimensional. there are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a 6-coordinate geometry to six equivalent Ge atoms. All Ta–Ge bond lengths are 2.72 Å. In the second Ta site, Ta is bonded in a 7-coordinate geometry to two equivalent B and five equivalent Ge atoms. Both Ta–B bond lengths are 2.32 Å. There are a spread of Ta–Ge bond distances ranging from 2.71–2.95 Å. B is bonded to six equivalent Ta atoms to form face-sharing BTa6 octahedra. Ge is bonded in a 9-coordinate geometry to nine Ta atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KTa2O6 by Materials Project

KTa2O6 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. K is bonded in a hexagonal planar geometry to six O atoms. There are two shorter (2.75 Å) and four longer (2.76 Å) K–O bond lengths. There are two inequivalent Ta sites. In the first Ta site, Ta is bonded to six O atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 36–38°. There is four shorter (1.99 Å) and two longer (2.00 Å) Ta–O bond length. In the second Ta site, Ta is bonded to six O atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 38°. There is four shorter (1.99 Å) and two longer (2.00 Å) Ta–O bond length. There are three inequivalent O sites. In the first O site, O is bonded in a 4-coordinate geometry to two equivalent K and two equivalent Ta atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two equivalent Ta atoms. In the third O site, O is bonded in a 2-coordinate geometry to one K and two Ta atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TaBe4Mo by Materials Project

Be4TaMo crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. there are three inequivalent Be sites. In the first Be site, Be is bonded to six equivalent Be and six equivalent Mo atoms to form BeBe6Mo6 cuboctahedra that share corners with twelve equivalent BeTa3Be6Mo3 cuboctahedra, edges with six equivalent BeBe6Mo6 cuboctahedra, and faces with twenty BeTa6Be6 cuboctahedra. All Be–Be bond lengths are 2.27 Å. All Be–Mo bond lengths are 2.66 Å. In the second Be site, Be is bonded to six equivalent Be and six equivalent Ta atoms to form BeTa6Be6 cuboctahedra that share corners with twelve equivalent BeTa3Be6Mo3 cuboctahedra, edges with six equivalent BeTa6Be6 cuboctahedra, and faces with twenty BeBe6Mo6 cuboctahedra. All Be–Be bond lengths are 2.31 Å. All Be–Ta bond lengths are 2.68 Å. In the third Be site, Be is bonded to six Be, three equivalent Ta, and three equivalent Mo atoms to form BeTa3Be6Mo3 cuboctahedra that share corners with eighteen BeBe6Mo6 cuboctahedra, edges with six equivalent BeTa3Be6Mo3 cuboctahedra, and faces with eighteen BeBe6Mo6 cuboctahedra. There are two shorter (2.22 Å) and two longer (2.33 Å) Be–Be bond lengths. There are two shorter (2.64 Å) and one longer (2.72 Å) Be–Ta bond lengths. There are one shorter (2.61 Å) and two longer (2.66 Å) Be–Mo bond lengths. Ta is bonded in a 1-coordinate geometry to twelve Be, three equivalent Ta, and one Mo atom. All Ta–Ta bond lengths are 2.83 Å. The Ta–Mo bond length is 2.72 Å. Mo is bonded in a 10-coordinate geometry to twelve Be and one Ta atom.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Exciton and biexciton transient absorption spectra of CdSe quantum dots with varying diameters

Transient absorption (TA) spectroscopy of semiconductor nanocrystals (NCs) is often used for excited state population analysis, but recent results suggest that TA bleach signals associated with multiexcitons in NCs do not scale linearly with exciton multiplicity. In this manuscript, we probe the factors that determine the intensities and spectral positions of exciton and biexciton components in the TA spectra of CdSe quantum dots (QDs) of five diameters. We find that, in all cases, the peak intensity of the biexciton TA spectrum is less than 1.5 times that of the single exciton TA spectrum, in stark contrast to a commonly made assumption that this ratio is 2. The relative intensities of the biexciton and exciton TA signals at each wavelength are determined by at least two factors: the TA spectral intensity and the spectral offset between the two signals. We do not observe correlations between either of these factors and the particle diameter, but we find that both are strongly impacted by replacing the native organic surface-capping ligands with a hole-trapping ligand. These results suggest that surface trapping plays an important role in determining the absolute intensities of TA features for CdSe QDs and not just their decay kinetics. Our work highlights the role of spectral offsets and the importance of surface trapping in governing absolute TA intensities. It also conclusively demonstrates that the biexciton TA spectra of CdSe QDs at the band gap energy are less than twice as intense as those of the exciton.

Chemistry↗