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DOE OSTI2020

Materials Data on Tb4Ni3Bi8 by Materials Project

Tb4Ni3Bi8 crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 12-coordinate geometry to four equivalent Ni and eight Bi atoms. All Tb–Ni bond lengths are 3.11 Å. There are four shorter (3.29 Å) and four longer (3.43 Å) Tb–Bi bond lengths. In the second Tb site, Tb is bonded in a 11-coordinate geometry to two equivalent Ni and nine Bi atoms. Both Tb–Ni bond lengths are 3.10 Å. There are four shorter (3.31 Å) and five longer (3.41 Å) Tb–Bi bond lengths. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded in a body-centered cubic geometry to four equivalent Tb and four equivalent Bi atoms. All Ni–Bi bond lengths are 2.67 Å. In the second Ni site, Ni is bonded in a body-centered cubic geometry to four equivalent Tb and four equivalent Bi atoms. All Ni–Bi bond lengths are 2.62 Å. There are four inequivalent Bi sites. In the first Bi site, Bi is bonded in a 7-coordinate geometry to five equivalent Tb and two equivalent Ni atoms. In the second Bi site, Bi is bonded in a 9-coordinate geometry to four equivalent Tb and four equivalent Ni atoms. In the third Bi site, Bi is bonded in a 8-coordinate geometry to four Tb and four equivalent Bi atoms. All Bi–Bi bond lengths are 3.21 Å. In the fourth Bi site, Bi is bonded in a 8-coordinate geometry to four Tb and four equivalent Bi atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb12Al7Si by Materials Project

Tb12Al7Si crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are three inequivalent Tb sites. In the first Tb site, Tb is bonded in a 4-coordinate geometry to six Al atoms. There are a spread of Tb–Al bond distances ranging from 2.99–3.73 Å. In the second Tb site, Tb is bonded in a 6-coordinate geometry to five Al and one Si atom. There are a spread of Tb–Al bond distances ranging from 3.06–3.35 Å. The Tb–Si bond length is 3.02 Å. In the third Tb site, Tb is bonded in a 5-coordinate geometry to five Al atoms. There are a spread of Tb–Al bond distances ranging from 3.13–3.52 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 9-coordinate geometry to nine Tb atoms. In the second Al site, Al is bonded in a body-centered cubic geometry to eight equivalent Tb atoms. In the third Al site, Al is bonded in a 10-coordinate geometry to nine Tb and one Al atom. The Al–Al bond length is 2.76 Å. Si is bonded in a 8-coordinate geometry to eight equivalent Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb4CdPt by Materials Project

Tb4PtCd crystallizes in the cubic F-43m space group. The structure is three-dimensional. there are three inequivalent Tb sites. In the first Tb site, Tb is bonded in a 3-coordinate geometry to three equivalent Pt and three equivalent Cd atoms. All Tb–Pt bond lengths are 2.88 Å. All Tb–Cd bond lengths are 3.44 Å. In the second Tb site, Tb is bonded in a distorted bent 150 degrees geometry to two equivalent Pt and two equivalent Cd atoms. Both Tb–Pt bond lengths are 2.86 Å. Both Tb–Cd bond lengths are 3.53 Å. In the third Tb site, Tb is bonded in a 4-coordinate geometry to two equivalent Pt and two equivalent Cd atoms. Both Tb–Pt bond lengths are 3.55 Å. Both Tb–Cd bond lengths are 3.29 Å. Pt is bonded in a 6-coordinate geometry to nine Tb atoms. Cd is bonded to nine Tb and three equivalent Cd atoms to form a mixture of distorted face and corner-sharing CdTb9Cd3 cuboctahedra. All Cd–Cd bond lengths are 3.19 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb2Fe14C by Materials Project

Tb2Fe14C crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 6-coordinate geometry to sixteen Fe atoms. There are a spread of Tb–Fe bond distances ranging from 2.97–3.23 Å. In the second Tb site, Tb is bonded in a 1-coordinate geometry to sixteen Fe and one C atom. There are a spread of Tb–Fe bond distances ranging from 3.00–3.35 Å. The Tb–C bond length is 2.80 Å. There are six inequivalent Fe sites. In the first Fe site, Fe is bonded to two Tb and ten Fe atoms to form a mixture of distorted face, edge, and corner-sharing FeTb2Fe10 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.37–2.62 Å. In the second Fe site, Fe is bonded to four Tb and eight Fe atoms to form a mixture of face and corner-sharing FeTb4Fe8 cuboctahedra. All Fe–Fe bond lengths are 2.49 Å. In the third Fe site, Fe is bonded in a water-like geometry to two equivalent Tb, four Fe, and two equivalent C atoms. There are two shorter (2.53 Å) and two longer (2.79 Å) Fe–Fe bond lengths. Both Fe–C bond lengths are 2.03 Å. In the fourth Fe site, Fe is bonded in a 2-coordinate geometry to two Tb and twelve Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.63–2.75 Å. In the fifth Fe site, Fe is bonded in a single-bond geometry to two Tb, seven Fe, and one C atom. The Fe–Fe bond length is 2.59 Å. The Fe–C bond length is 1.98 Å. In the sixth Fe site, Fe is bonded to three Tb and nine Fe atoms to form distorted FeTb3Fe9 cuboctahedra that share corners with fourteen FeTb2Fe10 cuboctahedra, edges with three FeTb3Fe9 cuboctahedra, and faces with twelve FeTb2Fe10 cuboctahedra. The Fe–Fe bond length is 2.40 Å. C is bonded in a 6-coordinate geometry to one Tb and six Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb10(SiSb)3 by Materials Project

Tb10(SiSb)3 crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. there are three inequivalent Tb sites. In the first Tb site, Tb is bonded in a 5-coordinate geometry to two equivalent Si and three equivalent Sb atoms. Both Tb–Si bond lengths are 3.46 Å. There are two shorter (3.04 Å) and one longer (3.17 Å) Tb–Sb bond lengths. In the second Tb site, Tb is bonded in a 5-coordinate geometry to three equivalent Si and two equivalent Sb atoms. There are two shorter (3.02 Å) and one longer (3.19 Å) Tb–Si bond lengths. Both Tb–Sb bond lengths are 3.46 Å. In the third Tb site, Tb is bonded in a 6-coordinate geometry to three equivalent Si and three equivalent Sb atoms. All Tb–Si bond lengths are 3.10 Å. All Tb–Sb bond lengths are 3.16 Å. Si is bonded in a 9-coordinate geometry to nine Tb atoms. Sb is bonded in a 9-coordinate geometry to nine Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb4CdPd by Materials Project

Tb4PdCd crystallizes in the cubic F-43m space group. The structure is three-dimensional. there are three inequivalent Tb sites. In the first Tb site, Tb is bonded in a 3-coordinate geometry to three equivalent Pd and three equivalent Cd atoms. All Tb–Pd bond lengths are 2.89 Å. All Tb–Cd bond lengths are 3.40 Å. In the second Tb site, Tb is bonded in a distorted bent 150 degrees geometry to two equivalent Pd and two equivalent Cd atoms. Both Tb–Pd bond lengths are 2.88 Å. Both Tb–Cd bond lengths are 3.54 Å. In the third Tb site, Tb is bonded in a 4-coordinate geometry to two equivalent Pd and two equivalent Cd atoms. Both Tb–Pd bond lengths are 3.57 Å. Both Tb–Cd bond lengths are 3.29 Å. Pd is bonded in a 6-coordinate geometry to nine Tb atoms. Cd is bonded to nine Tb and three equivalent Cd atoms to form a mixture of distorted face and corner-sharing CdTb9Cd3 cuboctahedra. All Cd–Cd bond lengths are 3.20 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb9Mg5Ni4 by Materials Project

Mg5Tb9Ni4 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a 9-coordinate geometry to one Mg and eight Tb atoms. The Mg–Mg bond length is 3.11 Å. There are four shorter (3.32 Å) and four longer (3.43 Å) Mg–Tb bond lengths. In the second Mg site, Mg is bonded in a body-centered cubic geometry to eight equivalent Tb atoms. All Mg–Tb bond lengths are 3.28 Å. There are three inequivalent Tb sites. In the first Tb site, Tb is bonded in a 2-coordinate geometry to six Mg and two equivalent Ni atoms. Both Tb–Ni bond lengths are 2.76 Å. In the second Tb site, Tb is bonded in a 4-coordinate geometry to four equivalent Mg and four equivalent Ni atoms. All Tb–Ni bond lengths are 2.92 Å. In the third Tb site, Tb is bonded in a square co-planar geometry to four equivalent Ni atoms. All Tb–Ni bond lengths are 2.94 Å. Ni is bonded in a 7-coordinate geometry to seven Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb2Al17 by Materials Project

Tb2Al17 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 12-coordinate geometry to eighteen Al atoms. There are a spread of Tb–Al bond distances ranging from 3.28–3.63 Å. In the second Tb site, Tb is bonded in a 2-coordinate geometry to twenty Al atoms. There are a spread of Tb–Al bond distances ranging from 3.12–3.53 Å. There are eight inequivalent Al sites. In the first Al site, Al is bonded in a 2-coordinate geometry to one Tb and nine Al atoms. There are a spread of Al–Al bond distances ranging from 2.64–3.11 Å. In the second Al site, Al is bonded to two equivalent Tb and ten Al atoms to form AlTb2Al10 cuboctahedra that share corners with fourteen AlTb2Al10 cuboctahedra, edges with six AlTb3Al9 cuboctahedra, and faces with ten AlTb2Al10 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.67–2.78 Å. In the third Al site, Al is bonded to two equivalent Tb and ten Al atoms to form AlTb2Al10 cuboctahedra that share corners with fourteen AlTb2Al10 cuboctahedra, edges with six AlTb3Al9 cuboctahedra, and faces with ten AlTb2Al10 cuboctahedra. There are four shorter (2.68 Å) and four longer (2.78 Å) Al–Al bond lengths. In the fourth Al site, Al is bonded in a 12-coordinate geometry to two Tb and ten Al atoms. There are a spread of Al–Al bond distances ranging from 2.74–2.93 Å. In the fifth Al site, Al is bonded in a 12-coordinate geometry to two Tb and eight Al atoms. There are a spread of Al–Al bond distances ranging from 2.73–2.96 Å. In the sixth Al site, Al is bonded in a 12-coordinate geometry to two Tb and eight Al atoms. There are two shorter (2.75 Å) and two longer (2.83 Å) Al–Al bond lengths. In the seventh Al site, Al is bonded to three Tb and nine Al atoms to form a mixture of distorted edge, face, and corner-sharing AlTb3Al9 cuboctahedra. Both Al–Al bond lengths are 2.71 Å. In the eighth Al site, Al is bonded to three Tb and nine Al atoms to form a mixture of distorted edge, face, and corner-sharing AlTb3Al9 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb7Co6Sn23 by Materials Project

Tb7Co6Sn23 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 12-coordinate geometry to six equivalent Co and twelve Sn atoms. All Tb–Co bond lengths are 3.44 Å. There are six shorter (3.37 Å) and six longer (3.38 Å) Tb–Sn bond lengths. In the second Tb site, Tb is bonded in a 12-coordinate geometry to two equivalent Co and ten Sn atoms. Both Tb–Co bond lengths are 3.17 Å. There are a spread of Tb–Sn bond distances ranging from 3.09–3.40 Å. Co is bonded in a 9-coordinate geometry to three Tb and six Sn atoms. There are a spread of Co–Sn bond distances ranging from 2.59–2.79 Å. There are six inequivalent Sn sites. In the first Sn site, Sn is bonded in a 12-coordinate geometry to three Tb, two equivalent Co, and one Sn atom. The Sn–Sn bond length is 2.98 Å. In the second Sn site, Sn is bonded in a 7-coordinate geometry to three equivalent Tb, three equivalent Co, and one Sn atom. The Sn–Sn bond length is 2.95 Å. In the third Sn site, Sn is bonded in a 6-coordinate geometry to six equivalent Sn atoms. All Sn–Sn bond lengths are 2.98 Å. In the fourth Sn site, Sn is bonded in a 5-coordinate geometry to four equivalent Tb, one Co, and one Sn atom. The Sn–Sn bond length is 3.18 Å. In the fifth Sn site, Sn is bonded in a 4-coordinate geometry to three equivalent Tb and one Sn atom. In the sixth Sn site, Sn is bonded in a 7-coordinate geometry to three Tb, two equivalent Co, and two Sn atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb6Br7 by Materials Project

Tb6Br7 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Tb sites. In the first Tb site, Tb is bonded in a distorted rectangular see-saw-like geometry to four Br atoms. There are a spread of Tb–Br bond distances ranging from 2.82–3.08 Å. In the second Tb site, Tb is bonded in a 3-coordinate geometry to three Br atoms. There are one shorter (3.00 Å) and two longer (3.02 Å) Tb–Br bond lengths. In the third Tb site, Tb is bonded to five Br atoms to form distorted edge-sharing TbBr5 square pyramids. There are a spread of Tb–Br bond distances ranging from 2.88–3.17 Å. There are four inequivalent Br sites. In the first Br site, Br is bonded in a square co-planar geometry to four equivalent Tb atoms. In the second Br site, Br is bonded in a 3-coordinate geometry to three Tb atoms. In the third Br site, Br is bonded in a distorted see-saw-like geometry to four Tb atoms. In the fourth Br site, Br is bonded in a 3-coordinate geometry to three Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb5Br8 by Materials Project

Tb5Br8 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Tb sites. In the first Tb site, Tb is bonded in a 5-coordinate geometry to five Br atoms. There are four shorter (2.92 Å) and one longer (3.46 Å) Tb–Br bond lengths. In the second Tb site, Tb is bonded in a rectangular see-saw-like geometry to four Br atoms. There are two shorter (2.88 Å) and two longer (3.05 Å) Tb–Br bond lengths. In the third Tb site, Tb is bonded to six Br atoms to form edge-sharing TbBr6 octahedra. There are four shorter (2.85 Å) and two longer (2.86 Å) Tb–Br bond lengths. There are four inequivalent Br sites. In the first Br site, Br is bonded in a 3-coordinate geometry to three Tb atoms. In the second Br site, Br is bonded in a distorted T-shaped geometry to three Tb atoms. In the third Br site, Br is bonded in a 2-coordinate geometry to three Tb atoms. In the fourth Br site, Br is bonded in a distorted T-shaped geometry to three Tb atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb5S7 by Materials Project

Tb5S7 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Tb sites. In the first Tb site, Tb is bonded to six S atoms to form TbS6 octahedra that share corners with two equivalent TbS6 octahedra, corners with four equivalent TbS7 pentagonal bipyramids, edges with two equivalent TbS6 octahedra, and edges with six equivalent TbS7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 56°. There are two shorter (2.69 Å) and four longer (2.77 Å) Tb–S bond lengths. In the second Tb site, Tb is bonded to six S atoms to form TbS6 octahedra that share corners with three TbS6 octahedra, corners with six equivalent TbS7 pentagonal bipyramids, edges with five equivalent TbS6 octahedra, and an edgeedge with one TbS7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 0–56°. There are a spread of Tb–S bond distances ranging from 2.70–2.83 Å. In the third Tb site, Tb is bonded to seven S atoms to form distorted TbS7 pentagonal bipyramids that share corners with eight TbS6 octahedra, edges with four TbS6 octahedra, edges with two equivalent TbS7 pentagonal bipyramids, and faces with two equivalent TbS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 22–68°. There are a spread of Tb–S bond distances ranging from 2.75–2.96 Å. There are four inequivalent S sites. In the first S site, S is bonded in a square co-planar geometry to four equivalent Tb atoms. In the second S site, S is bonded to five Tb atoms to form distorted STb5 trigonal bipyramids that share corners with four equivalent STb4 tetrahedra, corners with six STb5 trigonal bipyramids, edges with three equivalent STb4 tetrahedra, and edges with six STb5 trigonal bipyramids. In the third S site, S is bonded to four Tb atoms to form distorted STb4 tetrahedra that share corners with three equivalent STb4 tetrahedra, corners with nine STb5 trigonal bipyramids, and edges with four STb5 trigonal bipyramids. In the fourth S site, S is bonded to five Tb atoms to form STb5 trigonal bipyramids that share corners with five equivalent STb4 tetrahedra, corners with four equivalent STb5 trigonal bipyramids, an edgeedge with one STb4 tetrahedra, and edges with five STb5 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb4Ni13C4 by Materials Project

Tb4Ni13C4 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded in a 6-coordinate geometry to fourteen Ni atoms. There are a spread of Tb–Ni bond distances ranging from 2.68–3.05 Å. In the second Tb site, Tb is bonded in a 1-coordinate geometry to eleven Ni and four equivalent C atoms. There are a spread of Tb–Ni bond distances ranging from 2.64–3.22 Å. All Tb–C bond lengths are 2.72 Å. There are five inequivalent Ni sites. In the first Ni site, Ni is bonded in a linear geometry to four Tb and two equivalent C atoms. Both Ni–C bond lengths are 1.94 Å. In the second Ni site, Ni is bonded to four equivalent Tb and eight Ni atoms to form NiTb4Ni8 cuboctahedra that share corners with four equivalent CNi6 octahedra and faces with two equivalent NiTb4Ni8 cuboctahedra. The corner-sharing octahedral tilt angles are 34°. There are four shorter (2.43 Å) and four longer (2.52 Å) Ni–Ni bond lengths. In the third Ni site, Ni is bonded in a distorted bent 150 degrees geometry to four Tb and two C atoms. There is one shorter (1.89 Å) and one longer (1.92 Å) Ni–C bond length. In the fourth Ni site, Ni is bonded in a single-bond geometry to four Tb, three Ni, and one C atom. Both Ni–Ni bond lengths are 2.44 Å. The Ni–C bond length is 1.87 Å. In the fifth Ni site, Ni is bonded in a 3-coordinate geometry to three Tb and six Ni atoms. There are two inequivalent C sites. In the first C site, C is bonded in a 7-coordinate geometry to four equivalent Tb, two equivalent Ni, and one C atom. The C–C bond length is 1.36 Å. In the second C site, C is bonded to six Ni atoms to form CNi6 octahedra that share corners with two equivalent NiTb4Ni8 cuboctahedra and corners with two equivalent CNi6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb3SmNi4 by Materials Project

Tb3SmNi4 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. there are three inequivalent Tb sites. In the first Tb site, Tb is bonded in a 7-coordinate geometry to seven Ni atoms. There are a spread of Tb–Ni bond distances ranging from 2.85–2.93 Å. In the second Tb site, Tb is bonded in a 7-coordinate geometry to seven Ni atoms. There are a spread of Tb–Ni bond distances ranging from 2.84–2.97 Å. In the third Tb site, Tb is bonded in a 7-coordinate geometry to seven Ni atoms. There are a spread of Tb–Ni bond distances ranging from 2.86–2.93 Å. Sm is bonded in a 7-coordinate geometry to seven Ni atoms. There are a spread of Sm–Ni bond distances ranging from 2.88–2.95 Å. There are four inequivalent Ni sites. In the first Ni site, Ni is bonded in a 9-coordinate geometry to six Tb, one Sm, and two equivalent Ni atoms. Both Ni–Ni bond lengths are 2.60 Å. In the second Ni site, Ni is bonded in a 9-coordinate geometry to five Tb, two equivalent Sm, and two equivalent Ni atoms. Both Ni–Ni bond lengths are 2.61 Å. In the third Ni site, Ni is bonded in a 9-coordinate geometry to three Tb, four equivalent Sm, and two equivalent Ni atoms. In the fourth Ni site, Ni is bonded in a 9-coordinate geometry to seven Tb and two equivalent Ni atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb3Pm by Materials Project

Tb3Pm is Magnesium-derived structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Tb sites. In the first Tb site, Tb is bonded to eight equivalent Tb and four equivalent Pm atoms to form TbTb8Pm4 cuboctahedra that share corners with four equivalent PmTb12 cuboctahedra, corners with fourteen TbTb8Pm4 cuboctahedra, edges with six equivalent PmTb12 cuboctahedra, edges with twelve equivalent TbTb8Pm4 cuboctahedra, faces with four equivalent PmTb12 cuboctahedra, and faces with sixteen TbTb8Pm4 cuboctahedra. There are a spread of Tb–Tb bond distances ranging from 3.58–3.65 Å. There are two shorter (3.59 Å) and two longer (3.63 Å) Tb–Pm bond lengths. In the second Tb site, Tb is bonded to eight Tb and four equivalent Pm atoms to form TbTb8Pm4 cuboctahedra that share corners with four equivalent PmTb12 cuboctahedra, corners with fourteen TbTb8Pm4 cuboctahedra, edges with six equivalent PmTb12 cuboctahedra, edges with twelve TbTb8Pm4 cuboctahedra, faces with four equivalent PmTb12 cuboctahedra, and faces with sixteen TbTb8Pm4 cuboctahedra. There are a spread of Tb–Tb bond distances ranging from 3.58–3.65 Å. There are two shorter (3.59 Å) and two longer (3.63 Å) Tb–Pm bond lengths. Pm is bonded to twelve Tb atoms to form PmTb12 cuboctahedra that share corners with six equivalent PmTb12 cuboctahedra, corners with twelve equivalent TbTb8Pm4 cuboctahedra, edges with eighteen TbTb8Pm4 cuboctahedra, faces with eight equivalent PmTb12 cuboctahedra, and faces with twelve TbTb8Pm4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb3Ga2 by Materials Project

Tb3Ga2 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are three inequivalent Tb sites. In the first Tb site, Tb is bonded in a 4-coordinate geometry to six Ga atoms. There are a spread of Tb–Ga bond distances ranging from 2.93–3.72 Å. In the second Tb site, Tb is bonded in a 5-coordinate geometry to five Ga atoms. There are a spread of Tb–Ga bond distances ranging from 3.02–3.55 Å. In the third Tb site, Tb is bonded in a 6-coordinate geometry to six Ga atoms. There are a spread of Tb–Ga bond distances ranging from 2.99–3.33 Å. There are four inequivalent Ga sites. In the first Ga site, Ga is bonded in a 8-coordinate geometry to eight equivalent Tb atoms. In the second Ga site, Ga is bonded in a body-centered cubic geometry to eight equivalent Tb atoms. In the third Ga site, Ga is bonded in a 9-coordinate geometry to nine Tb atoms. In the fourth Ga site, Ga is bonded in a 10-coordinate geometry to nine Tb and one Ga atom. The Ga–Ga bond length is 2.80 Å.

36 MATERIALS SCIENCE↗
NASA NTRSDate not supplied

Systematic Errors in Simulated L-Band Brightness Temperature in the SMAP Level-4 Soil Moisture Analysis

The NASA Soil Moisture Active Passive (SMAP) mission has been providing L-band (1.4 GHz) brightness temperature (Tb) observations since April 2015. By assimilating the Tb observations into the NASA Catchment land surface model using a spatially distributed ensemble Kalman filter (EnKF), the SMAP Level-4 Soil Moisture (L4_SM) product provides global, 3-hourly, 9-km resolution estimates of surface (0-5 cm) and root-zone (0-100 cm) soil moisture with ~2.5-day latency for use in research and applications. The EnKF-based L4_SM analysis assumes unbiased forecast errors. Consequently, the seasonally varying bias between the model forecast Tb and the observed values is removed prior to the assimilation of the SMAP Tb observations. The L4_SM system is thus designed to only correct errors in synoptic-scale and interannual variations from the long-term mean seasonal cycle while maintaining the model’s (possibly wrong) climatology. In this paper, we examine the Tb observation-minus-forecast (O-F) residuals from the L4_SM Version 7 product (computed after rescaling the Tb observations to the mean seasonal cycle of the simulated Tb). The long-term average of the Tb O-F residuals has a global mean of only 0.13 K and locally small values, ranging from -1 to 3 K. The model forecast Tb, however, still exhibits undesirable systematic errors relative to the (rescaled) Tb observations. At some locations, the time-average Tb O-F values strongly depend on surface soil moisture (SM). At the Yanco SMAP core validation site, for example, the Tb O-F residuals typically range from 5 to 15 K under dry soil moisture conditions (SM < 0.15 m3 m-3) yet are predominantly negative under wet soil moisture conditions (SM > 0.25 m3 m-3), with values ranging from 0 to -40 K. This results in soil moisture analysis increments that persistently make the soil drier under dry SM conditions and persistently make the soil wetter under wet SM conditions, suggesting an error in the dynamic range of the simulated Tb, soil moisture or soil temperature. In this paper, we describe the higher-order systematic Tb forecast errors in more detail, examine their impact on the L4_SM product quality, and explore potential avenues to improve the L4_SM algorithm.

Rolf Reichle↗
DOE OSTI2020

Materials Data on Tb5Ge4 by Materials Project

Tb5Ge4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Tb sites. In the first Tb site, Tb is bonded to six Ge atoms to form corner-sharing TbGe6 octahedra. The corner-sharing octahedra tilt angles range from 52–54°. There are a spread of Tb–Ge bond distances ranging from 2.98–3.14 Å. In the second Tb site, Tb is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of Tb–Ge bond distances ranging from 2.99–3.64 Å. In the third Tb site, Tb is bonded in a 6-coordinate geometry to six Ge atoms. There are a spread of Tb–Ge bond distances ranging from 2.88–3.07 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to eight Tb and one Ge atom. The Ge–Ge bond length is 2.74 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to eight Tb and one Ge atom. In the third Ge site, Ge is bonded in a 8-coordinate geometry to eight Tb atoms.

36 MATERIALS SCIENCE↗