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At least 145 records · Page 8
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DOE OSTI2020

Materials Data on Tb(SiRu)2 by Materials Project

TbRu2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb3+ is bonded in a 8-coordinate geometry to eight equivalent Si4- atoms. All Tb–Si bond lengths are 3.22 Å. Ru+2.50+ is bonded to four equivalent Si4- atoms to form a mixture of corner and edge-sharing RuSi4 tetrahedra. All Ru–Si bond lengths are 2.38 Å. Si4- is bonded in a 4-coordinate geometry to four equivalent Tb3+ and four equivalent Ru+2.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(CoB)2 by Materials Project

TbCo2B2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb3+ is bonded in a body-centered cubic geometry to eight equivalent B3- atoms. All Tb–B bond lengths are 2.90 Å. Co+1.50+ is bonded to four equivalent B3- atoms to form a mixture of distorted corner and edge-sharing CoB4 tetrahedra. All Co–B bond lengths are 2.00 Å. B3- is bonded in a 4-coordinate geometry to four equivalent Tb3+ and four equivalent Co+1.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(SiPd)2 by Materials Project

TbPd2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb4+ is bonded to eight equivalent Si4- atoms to form TbSi8 hexagonal bipyramids that share corners with sixteen equivalent PdSi4 tetrahedra, edges with four equivalent TbSi8 hexagonal bipyramids, edges with eight equivalent PdSi4 tetrahedra, and faces with four equivalent TbSi8 hexagonal bipyramids. All Tb–Si bond lengths are 3.17 Å. Pd2+ is bonded to four equivalent Si4- atoms to form PdSi4 tetrahedra that share corners with eight equivalent TbSi8 hexagonal bipyramids, corners with four equivalent PdSi4 tetrahedra, edges with four equivalent TbSi8 hexagonal bipyramids, and edges with four equivalent PdSi4 tetrahedra. All Pd–Si bond lengths are 2.47 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tb4+, four equivalent Pd2+, and one Si4- atom. The Si–Si bond length is 2.33 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(SiNi)2 by Materials Project

TbNi2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb4+ is bonded in a distorted body-centered cubic geometry to eight equivalent Si4- atoms. All Tb–Si bond lengths are 3.06 Å. Ni2+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing NiSi4 tetrahedra. All Ni–Si bond lengths are 2.31 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tb4+, four equivalent Ni2+, and one Si4- atom. The Si–Si bond length is 2.42 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(SiAg)2 by Materials Project

TbAg2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb4+ is bonded to eight equivalent Si4- atoms to form TbSi8 hexagonal bipyramids that share corners with sixteen equivalent AgSi4 tetrahedra, edges with four equivalent TbSi8 hexagonal bipyramids, edges with eight equivalent AgSi4 tetrahedra, and faces with four equivalent TbSi8 hexagonal bipyramids. All Tb–Si bond lengths are 3.16 Å. Ag2+ is bonded to four equivalent Si4- atoms to form AgSi4 tetrahedra that share corners with eight equivalent TbSi8 hexagonal bipyramids, corners with four equivalent AgSi4 tetrahedra, edges with four equivalent TbSi8 hexagonal bipyramids, and edges with four equivalent AgSi4 tetrahedra. All Ag–Si bond lengths are 2.60 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tb4+, four equivalent Ag2+, and one Si4- atom. The Si–Si bond length is 2.30 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(FeSi)2 by Materials Project

TbFe2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb3+ is bonded in a distorted body-centered cubic geometry to eight equivalent Si4- atoms. All Tb–Si bond lengths are 3.09 Å. Fe+2.50+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing FeSi4 tetrahedra. All Fe–Si bond lengths are 2.27 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tb3+, four equivalent Fe+2.50+, and one Si4- atom. The Si–Si bond length is 2.58 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(SiOs)2 by Materials Project

TbOs2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb3+ is bonded in a 8-coordinate geometry to eight equivalent Os+1.50- atoms. All Tb–Os bond lengths are 3.20 Å. Os+1.50- is bonded in a 4-coordinate geometry to four equivalent Tb3+ and four equivalent Si atoms. All Os–Si bond lengths are 2.40 Å. Si is bonded in a 5-coordinate geometry to four equivalent Os+1.50- and one Si atom. The Si–Si bond length is 2.49 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(NiP)2 by Materials Project

TbNi2P2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb3+ is bonded in a distorted body-centered cubic geometry to eight equivalent P3- atoms. All Tb–P bond lengths are 2.98 Å. Ni+1.50+ is bonded to four equivalent P3- atoms to form a mixture of edge and corner-sharing NiP4 tetrahedra. All Ni–P bond lengths are 2.28 Å. P3- is bonded in a 9-coordinate geometry to four equivalent Tb3+, four equivalent Ni+1.50+, and one P3- atom. The P–P bond length is 2.32 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(MnSi)2 by Materials Project

TbMn2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb4+ is bonded in a body-centered cubic geometry to eight equivalent Si4- atoms. All Tb–Si bond lengths are 3.03 Å. Mn2+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing MnSi4 tetrahedra. All Mn–Si bond lengths are 2.37 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tb4+, four equivalent Mn2+, and one Si4- atom. The Si–Si bond length is 2.50 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(SiAu)2 by Materials Project

TbAu2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb3+ is bonded to eight equivalent Si4- atoms to form TbSi8 hexagonal bipyramids that share corners with sixteen equivalent AuSi4 tetrahedra, edges with four equivalent TbSi8 hexagonal bipyramids, edges with eight equivalent AuSi4 tetrahedra, and faces with four equivalent TbSi8 hexagonal bipyramids. All Tb–Si bond lengths are 3.23 Å. Au+2.50+ is bonded to four equivalent Si4- atoms to form AuSi4 tetrahedra that share corners with eight equivalent TbSi8 hexagonal bipyramids, corners with four equivalent AuSi4 tetrahedra, edges with four equivalent TbSi8 hexagonal bipyramids, and edges with four equivalent AuSi4 tetrahedra. All Au–Si bond lengths are 2.57 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tb3+, four equivalent Au+2.50+, and one Si4- atom. The Si–Si bond length is 2.30 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(CrSi)2 by Materials Project

TbCr2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tb3+ is bonded in a body-centered cubic geometry to eight equivalent Si4- atoms. All Tb–Si bond lengths are 3.00 Å. Cr+2.50+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing CrSi4 tetrahedra. All Cr–Si bond lengths are 2.41 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tb3+, four equivalent Cr+2.50+, and one Si4- atom. The Si–Si bond length is 2.48 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(CuS)3 by Materials Project

TbCu3S3 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Tb3+ is bonded to six equivalent S2- atoms to form TbS6 octahedra that share corners with twelve equivalent CuS4 tetrahedra, edges with three equivalent TbS6 octahedra, and edges with six equivalent CuS4 tetrahedra. All Tb–S bond lengths are 2.75 Å. Cu1+ is bonded to four equivalent S2- atoms to form CuS4 tetrahedra that share corners with four equivalent TbS6 octahedra, corners with six equivalent CuS4 tetrahedra, edges with two equivalent TbS6 octahedra, and edges with three equivalent CuS4 tetrahedra. The corner-sharing octahedra tilt angles range from 17–55°. There are a spread of Cu–S bond distances ranging from 2.32–2.41 Å. S2- is bonded in a 6-coordinate geometry to two equivalent Tb3+ and four equivalent Cu1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(BIr)2 by Materials Project

Tb(IrB)2 crystallizes in the tetragonal P4_2/n space group. The structure is zero-dimensional and consists of four terbium molecules and eight IrB clusters. In each IrB cluster, Ir is bonded in a single-bond geometry to one B atom. The Ir–B bond length is 1.78 Å. B is bonded in a single-bond geometry to one Ir atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(Mo3S4)2 by Materials Project

TbMo6S8 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Tb3+ is bonded in a body-centered cubic geometry to eight S2- atoms. There are two shorter (2.73 Å) and six longer (3.00 Å) Tb–S bond lengths. Mo+2.17+ is bonded to five S2- atoms to form a mixture of edge and corner-sharing MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.41–2.59 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 1-coordinate geometry to one Tb3+ and three equivalent Mo+2.17+ atoms. In the second S2- site, S2- is bonded in a 5-coordinate geometry to one Tb3+ and four equivalent Mo+2.17+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb(BC)2 by Materials Project

TbB2C2 crystallizes in the tetragonal P4_2/mmc space group. The structure is three-dimensional. Tb4+ is bonded in a 8-coordinate geometry to eight equivalent C2- atoms. All Tb–C bond lengths are 2.72 Å. B is bonded in a 2-coordinate geometry to one B and two equivalent C2- atoms. The B–B bond length is 1.64 Å. Both B–C bond lengths are 1.61 Å. C2- is bonded in a 2-coordinate geometry to four equivalent Tb4+, two equivalent B, and one C2- atom. The C–C bond length is 1.43 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Intrinsically Chiral Twist‐Bend Nematogens: Interplay of Molecular and Structural Chirality in the N TB Phase

Abstract Non‐symmetric lactate‐based chiral liquid crystal dimers containing an odd‐membered spacer are shown to exhibit a chiral twist‐bend nematic phase which is stable on cooling to room temperature. A comparison of racemic and optically pure materials reveals that the pitch length in the N* TB phase is not influenced by molecular chirality, whereas the nematic‐twist‐bend nematic transition temperature is increased.

Chemistry↗
DOE OSTI2024

Tailored (La 0.2 Pr 0.2 Nd 0.2 Tb 0.2 Dy 0.2 ) 2 Ce 2 O 7 as a Highly Active and Stable Nanocatalyst for the Oxygen Evolution Reaction

Abstract Designing highly active and robust catalysts for the oxygen evolution reaction is key to improving the overall efficiency of the water splitting reaction. It has been previously demonstrated that evaporation induced self‐assembly (EISA) can be used to synthesize highly porous and high surface area cerate‐based fluorite nanocatalysts, and that substitution of Ce with 50% rare earth (RE) cations significantly improves electrocatalyst activity. Herein, the defect structure of the best performing nanocatalyst in the series are further explored, Nd 2 Ce 2 O 7 , with a combination of neutron diffraction and neutron pair distribution function analysis. It is found that Nd 3 + cation substitution for Ce in the CeO 2 fluorite lattice introduces higher levels of oxygen Frenkel defects and induces a partially reduced RE 1.5 Ce 1.5 O 5 +x phase with oxygen vacancy ordering. Significantly, it is demonstrated that the concentration of oxygen Frenkel defects and improved electrocatalytic activity can be further enhanced by increasing the compositional complexity (number of RE cations involved) in the substitution. The resulting novel compositionally‐complex fluorite– (La 0.2 Pr 0.2 Nd 0.2 Tb 0.2 Dy 0.2 ) 2 Ce 2 O 7 is shown to display a low OER overpotential of 210 mV at a current density of 10 mAcm −2 in 1M KOH, and excellent cycling stability. It is suggested that increasing the compositional complexity of fluorite nanocatalysts expands the ability to tailor catalyst design.

Chemistry↗
DOE OSTI2020

Syntheses and Crystal Structures of Rare-Earth Oxyapatites Ca 2 RE 8 (SiO 4 ) 6 O 2 (RE = Pr, Tb, Ho, Tm)

Four different rare-earth oxyapatites of Ca 2 RE 8 (SiO 4 ) 6 O 2 (RE = Pr, Tb, Ho, Tm) were synthesized using a solution-based method followed by drying, calcination, and high-temperature sintering in air. X-ray powder diffraction and Raman spectroscopy were performed on the synthesized oxyapatites. Here, the RE oxyapatites crystallize in the hexagonal space group P6 3 /m with similar unit cell parameters, increasing linearly with larger RE cations. The unit cell volumes increase linearly whereas the densities decrease nonlinearly with larger RE cations. Raman spectra showed intense bands of the symmetric bending and stretching modes of SiO 4 at ~ 400 and 860 cm -1 regions, respectively. The bands generally shifted to higher frequencies with smaller RE cations in the structures.

36 MATERIALS SCIENCE↗