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At least 667 records · Page 37
All sourcesNASA NTRSDOE OSTI
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↗
DOE OSTI2022

LANL Meteorological Program: 2021 Data Completeness/Quality Report

Los Alamos National Laboratory (LANL) operates seven mesa-top instrumented meteorology towers: Technical Area (TA) 6, TA-49, TA-53, TA-54, TA-63, TA-54B, and TA-16B. An additional instrumented tower is located in Mortandad Canyon (TA-5 MDCN), and there is a rain gauge at North Community (NCOM), located within the town of Los Alamos. The 10 meter (m) towers at TA-63, TA54B, and TA-16B were installed in 2021, and will be included in the 2022 data completeness/quality report.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Materials Data on Li7TaN4 by Materials Project

Li7TaN4 crystallizes in the cubic Pa-3 space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four N3- atoms to form distorted LiN4 tetrahedra that share corners with two equivalent TaN4 tetrahedra, corners with fourteen LiN4 tetrahedra, an edgeedge with one TaN4 tetrahedra, and edges with five LiN4 tetrahedra. There are a spread of Li–N bond distances ranging from 2.11–2.26 Å. In the second Li1+ site, Li1+ is bonded to four N3- atoms to form LiN4 tetrahedra that share corners with four equivalent TaN4 tetrahedra, corners with twelve LiN4 tetrahedra, and edges with six LiN4 tetrahedra. There are one shorter (2.15 Å) and three longer (2.19 Å) Li–N bond lengths. In the third Li1+ site, Li1+ is bonded to four N3- atoms to form distorted LiN4 tetrahedra that share corners with two equivalent TaN4 tetrahedra, corners with fourteen LiN4 tetrahedra, an edgeedge with one TaN4 tetrahedra, and edges with five LiN4 tetrahedra. There are a spread of Li–N bond distances ranging from 2.10–2.25 Å. Ta5+ is bonded to four N3- atoms to form TaN4 tetrahedra that share corners with sixteen LiN4 tetrahedra and edges with six LiN4 tetrahedra. There is one shorter (1.96 Å) and three longer (1.98 Å) Ta–N bond length. There are twelve inequivalent N3- sites. In the first N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. The N–Ta bond length is 1.98 Å. In the second N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.15–2.26 Å. The N–Ta bond length is 1.98 Å. In the third N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. The N–Li bond length is 2.19 Å. The N–Ta bond length is 1.98 Å. In the fourth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. The N–Ta bond length is 1.98 Å. In the fifth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.15–2.26 Å. The N–Ta bond length is 1.98 Å. In the sixth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.21 Å. The N–Ta bond length is 1.98 Å. In the seventh N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. In the eighth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.21 Å. In the ninth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. In the tenth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are a spread of N–Li bond distances ranging from 2.10–2.26 Å. The N–Ta bond length is 1.98 Å. In the eleventh N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. The N–Li bond length is 2.15 Å. In the twelfth N3- site, N3- is bonded in a body-centered cubic geometry to seven Li1+ and one Ta5+ atom. There are three shorter (2.11 Å) and three longer (2.25 Å) N–Li bond lengths. The N–Ta bond length is 1.96 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta5Ge3 by Materials Project

Ta5Ge3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a 5-coordinate geometry to five Ge atoms. There are a spread of Ta–Ge bond distances ranging from 2.68–2.76 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 0–49°. There are four shorter (2.59 Å) and two longer (3.03 Å) Ta–Ge bond lengths. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to eight Ta and one Ge atom. The Ge–Ge bond length is 2.57 Å. In the second Ge site, Ge is bonded in a 10-coordinate geometry to ten Ta atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta5Si3 by Materials Project

Ta5Si3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a 5-coordinate geometry to five Si atoms. There are a spread of Ta–Si bond distances ranging from 2.61–2.73 Å. In the second Ta site, Ta is bonded to six Si atoms to form distorted corner-sharing TaSi6 octahedra. The corner-sharing octahedra tilt angles range from 0–51°. There are four shorter (2.57 Å) and two longer (2.98 Å) Ta–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded in a 10-coordinate geometry to ten Ta atoms. In the second Si site, Si is bonded in a 9-coordinate geometry to eight Ta and one Si atom. The Si–Si bond length is 2.41 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta2Se8I by Materials Project

(TaSe4)2I crystallizes in the tetragonal I422 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 in a 8-coordinate geometry to eight Se1- atoms. There are four shorter (2.62 Å) and four longer (2.73 Å) Ta–Se bond lengths. In the second Ta+4.50+ site, Ta+4.50+ is bonded in a 8-coordinate geometry to eight Se1- atoms. There are four shorter (2.65 Å) and four longer (2.70 Å) Ta–Se bond lengths. There are two inequivalent Se1- sites. In the first Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ atoms. In the second Se1- site, Se1- is bonded in a 2-coordinate geometry to two Ta+4.50+ and one I1- atom. The Se–I bond length is 3.33 Å. I1- is bonded in a 4-coordinate geometry to four equivalent Se1- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta4MnS8 by Materials Project

Ta4MnS8 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Ta+3.50+ sites. In the first Ta+3.50+ site, Ta+3.50+ is bonded to six S2- atoms to form distorted TaS6 pentagonal pyramids that share corners with four equivalent MnS6 octahedra and edges with six TaS6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 48°. There are two shorter (2.46 Å) and four longer (2.50 Å) Ta–S bond lengths. In the second Ta+3.50+ site, Ta+3.50+ is bonded to six equivalent S2- atoms to form distorted TaS6 pentagonal pyramids that share edges with six equivalent TaS6 pentagonal pyramids and faces with two equivalent MnS6 octahedra. All Ta–S bond lengths are 2.50 Å. Mn2+ is bonded to six equivalent S2- atoms to form MnS6 octahedra that share corners with twelve equivalent TaS6 pentagonal pyramids and faces with two equivalent TaS6 pentagonal pyramids. All Mn–S bond lengths are 2.50 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Ta+3.50+ and one Mn2+ atom. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Ta+3.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta4FeS8 by Materials Project

Ta4FeS8 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Ta+3.50+ sites. In the first Ta+3.50+ site, Ta+3.50+ is bonded to six S2- atoms to form distorted TaS6 pentagonal pyramids that share corners with four equivalent FeS6 octahedra and edges with six TaS6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 48°. There are two shorter (2.45 Å) and four longer (2.51 Å) Ta–S bond lengths. In the second Ta+3.50+ site, Ta+3.50+ is bonded to six equivalent S2- atoms to form distorted TaS6 pentagonal pyramids that share edges with six equivalent TaS6 pentagonal pyramids and faces with two equivalent FeS6 octahedra. All Ta–S bond lengths are 2.46 Å. Fe2+ is bonded to six equivalent S2- atoms to form FeS6 octahedra that share corners with twelve equivalent TaS6 pentagonal pyramids and faces with two equivalent TaS6 pentagonal pyramids. All Fe–S bond lengths are 2.33 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Ta+3.50+ and one Fe2+ atom. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Ta+3.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TaIr by Materials Project

IrTa is Tetraauricupride-like structured and crystallizes in the orthorhombic Pmma 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 eight Ir atoms. There are a spread of Ta–Ir bond distances ranging from 2.79–2.87 Å. In the second Ta site, Ta is bonded in a 12-coordinate geometry to eight Ir atoms. There are a spread of Ta–Ir bond distances ranging from 2.77–2.84 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 12-coordinate geometry to eight Ta atoms. In the second Ir site, Ir is bonded in a 12-coordinate geometry to eight Ta atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr3LiTa4(O6F)2 by Materials Project

LiSr3Ta4(O6F)2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Li1+ is bonded in a distorted linear geometry to six equivalent O2- and two equivalent F1- atoms. All Li–O bond lengths are 2.76 Å. Both Li–F bond lengths are 1.97 Å. Sr2+ is bonded to six O2- and two equivalent F1- atoms to form distorted SrO6F2 hexagonal bipyramids that share edges with four equivalent SrO6F2 hexagonal bipyramids and edges with six TaO6 octahedra. There are four shorter (2.67 Å) and two longer (2.69 Å) Sr–O bond lengths. Both Sr–F bond lengths are 2.43 Å. There are two inequivalent Ta+4.75+ sites. In the first Ta+4.75+ site, Ta+4.75+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and edges with four equivalent SrO6F2 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 39–45°. There are four shorter (2.01 Å) and two longer (2.02 Å) Ta–O bond lengths. In the second Ta+4.75+ site, Ta+4.75+ is bonded to six equivalent O2- atoms to form TaO6 octahedra that share corners with six equivalent TaO6 octahedra and edges with six equivalent SrO6F2 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 45°. All Ta–O bond lengths are 2.03 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sr2+ and two Ta+4.75+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Li1+, one Sr2+, and two equivalent Ta+4.75+ atoms. F1- is bonded to one Li1+ and three equivalent Sr2+ atoms to form distorted corner-sharing FSr3Li tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sm3Ta17O47 by Materials Project

Sm3Ta17O47 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. there are two inequivalent Sm3+ sites. In the first Sm3+ site, Sm3+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Sm–O bond distances ranging from 2.43–2.58 Å. In the second Sm3+ site, Sm3+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Sm–O bond distances ranging from 2.42–2.73 Å. There are nine inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one TaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 20–36°. There are a spread of Ta–O bond distances ranging from 1.92–2.11 Å. 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 1–32°. There are a spread of Ta–O bond distances ranging from 1.88–2.18 Å. In the third Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one TaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 3–40°. There are a spread of Ta–O bond distances ranging from 1.94–2.18 Å. In the fourth Ta5+ site, Ta5+ is bonded to six O2- atoms to form distorted corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 1–39°. There are a spread of Ta–O bond distances ranging from 1.89–2.19 Å. In the fifth Ta5+ site, Ta5+ is bonded to seven O2- atoms to form TaO7 pentagonal bipyramids that share corners with two equivalent TaO7 pentagonal bipyramids and edges with five TaO6 octahedra. There are a spread of Ta–O bond distances ranging from 1.96–2.15 Å. In the sixth Ta5+ site, Ta5+ is bonded to six O2- atoms to form distorted TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one TaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 21–36°. There are a spread of Ta–O bond distances ranging from 1.85–2.16 Å. In the seventh Ta5+ site, Ta5+ is bonded to six O2- atoms to form distorted TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one TaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 20–38°. There are a spread of Ta–O bond distances ranging from 1.85–2.12 Å. In the eighth Ta5+ site, Ta5+ is bonded to six O2- atoms to form distorted TaO6 octahedra that share corners with six TaO6 octahedra and an edgeedge with one TaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 16–40°. There are a spread of Ta–O bond distances ranging from 1.90–2.07 Å. 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 0–30°. There are a spread of Ta–O bond distances ranging from 1.96–2.03 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Sm3+ and two equivalent Ta5+ atoms. In the second O2- site, O2- is bonded to two equivalent Sm3+ and two Ta5+ atoms to form a mixture of distorted edge and corner-sharing OSm2Ta2 tetrahedra. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two Ta5+ atoms. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to two Ta5+ atoms. In the fifth O2- site, O2- is bonded in a distorted T-shaped geometry to one Sm3+ and two equivalent Ta5+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to three Ta5+ atoms. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two Ta5+ atoms. In the eighth O2- site, O2- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to two Ta5+ atoms. In the tenth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sm3+ and two Ta5+ atoms. In the eleventh O2- site, O2- is bonded in a distorted T-shaped geometry to three Ta5+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Sm3+ and two Ta5+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted T-shaped geometry to one Sm3+ and two equivalent Ta5+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ta5+ atoms. In the fifteenth O2- site, O2- is bonded in a linear geometry to two equivalent Ta5+ atoms. In the sixteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two Ta5+ atoms. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to one Sm3+ and two equivalent Ta5+ atoms. In the eighteenth O2- site, O2- is bonded in a bent 150 degrees geometry to two Ta5+ atoms. In the nineteenth O2- site, O2- is bonded to two equivalent Sm3+ and two Ta5+ atoms to form distorted corner-sharing OSm2Ta2 tetrahedra. In the twentieth O2- site, O2- is bonded in a 3-coordinate geometry to one Sm3+ and two equivalent Ta5+ atoms. In the twenty-first O2- site, O2- is bonded in a 3-coordinate geometry to three Ta5+ atoms. In the twenty-second O2- site, O2- is bonded in a distorted trigonal planar geometry to three Ta5+ atoms. In the twenty-third O2- site, O2- is bonded in a 2-coordinate geometry to one Sm3+ and two equivalent Ta5+ atoms. In the twenty-fourth O2- site, O2- is bonded in a linear geometry to two equivalent Ta5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Lu2Ta2O5 by Materials Project

Lu2Ta2O5 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Lu is bonded in a 5-coordinate geometry to five O atoms. There are four shorter (2.21 Å) and one longer (2.30 Å) Lu–O bond lengths. There are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a body-centered cubic geometry to eight equivalent O atoms. All Ta–O bond lengths are 2.11 Å. In the second Ta site, Ta is bonded in a square co-planar geometry to four equivalent O atoms. All Ta–O bond lengths are 2.45 Å. There are two inequivalent O sites. In the first O site, O is bonded to two equivalent Lu and two equivalent Ta atoms to form OLu2Ta2 tetrahedra that share corners with two equivalent OLu2Ta4 octahedra, corners with ten equivalent OLu2Ta2 tetrahedra, and edges with five equivalent OLu2Ta2 tetrahedra. The corner-sharing octahedral tilt angles are 52°. In the second O site, O is bonded to two equivalent Lu and four equivalent Ta atoms to form OLu2Ta4 octahedra that share corners with four equivalent OLu2Ta4 octahedra, corners with eight equivalent OLu2Ta2 tetrahedra, and edges with four equivalent OLu2Ta4 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta4N3 by Materials Project

Ta4N3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a square co-planar geometry to four N atoms. There are two shorter (2.16 Å) and two longer (2.20 Å) Ta–N bond lengths. In the second Ta site, Ta is bonded to five N atoms to form a mixture of corner and edge-sharing TaN5 square pyramids. There are four shorter (2.21 Å) and one longer (2.27 Å) Ta–N bond lengths. There are two inequivalent N sites. In the first N site, N is bonded to six Ta atoms to form a mixture of corner and edge-sharing NTa6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. In the second N site, N is bonded to six Ta atoms to form a mixture of corner and edge-sharing NTa6 octahedra. The corner-sharing octahedral tilt angles are 0°.

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