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At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Yb(NiGe)2 by Materials Project

YbNi2Ge2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Yb is bonded in a 8-coordinate geometry to eight equivalent Ni and eight equivalent Ge atoms. All Yb–Ni bond lengths are 3.20 Å. All Yb–Ge bond lengths are 3.13 Å. Ni is bonded in a 4-coordinate geometry to four equivalent Yb and four equivalent Ge atoms. All Ni–Ge bond lengths are 2.35 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Yb, four equivalent Ni, and one Ge atom. The Ge–Ge bond length is 2.56 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb(TiAl10)2 by Materials Project

Yb(TiAl10)2 crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Yb is bonded in a 4-coordinate geometry to sixteen Al atoms. There are four shorter (3.18 Å) and twelve longer (3.23 Å) Yb–Al bond lengths. Ti is bonded to twelve Al atoms to form TiAl12 cuboctahedra that share corners with six equivalent TiAl12 cuboctahedra, edges with eighteen equivalent AlYbTiAl10 cuboctahedra, and faces with six equivalent AlYbTiAl10 cuboctahedra. There are six shorter (2.61 Å) and six longer (2.86 Å) Ti–Al bond lengths. There are three inequivalent Al sites. In the first Al site, Al is bonded to one Yb, one Ti, and ten Al atoms to form distorted AlYbTiAl10 cuboctahedra that share corners with fifteen equivalent AlYbTiAl10 cuboctahedra, edges with two equivalent AlYbTiAl10 cuboctahedra, edges with three equivalent TiAl12 cuboctahedra, a faceface with one TiAl12 cuboctahedra, and faces with fifteen equivalent AlYbTiAl10 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.74–3.13 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to two equivalent Ti and ten Al atoms. All Al–Al bond lengths are 2.88 Å. In the third Al site, Al is bonded in a linear geometry to two equivalent Yb and twelve equivalent Al atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb by Materials Project

Yb is Magnesium structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Yb is bonded to twelve equivalent Yb atoms to form a mixture of face, edge, and corner-sharing YbYb12 cuboctahedra. There are six shorter (3.85 Å) and six longer (3.89 Å) Yb–Yb bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb by Materials Project

Yb is Copper structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Yb is bonded to twelve equivalent Yb atoms to form a mixture of edge, corner, and face-sharing YbYb12 cuboctahedra. All Yb–Yb bond lengths are 3.85 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb by Materials Project

Yb is Tungsten structured and crystallizes in the cubic Im-3m space group. The structure is three-dimensional. Yb is bonded in a distorted body-centered cubic geometry to eight equivalent Yb atoms. All Yb–Yb bond lengths are 3.73 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Structural and Spectroscopic Analysis of Ln(II) 18-crown-6 and Benzo-18-crown-6 Complexes (Ln = Sm, Eu, Yb)

Three Ln 2+ 18-crown-6 complexes of the formula Ln(18-crown-6)I 2 (Ln = Sm, Eu, Yb) were isolated from the explicit synthesis of the corresponding LnI 2 salts with 18-crown-6 and tetrabutylammonium tetraphenylborate in organic media under air-free conditions. Each metal complex forms a distorted hexagonal bipyramidal geometry and crystallizes in the monoclinic space group P2 1 /n. Comparatively, crystallization of Ln(benzo-18-crown-6)I 2 (Ln = Sm, Eu, Yb) from the reaction of LnI2 with tetrabutylammonium tetraphenylborate and benzo-18-crown-6 in THF/ethanol under similarly air-free conditions yields two polymorphs. The first form, α, crystallizes in the monoclinic space group P2 1 /c (or the nonstandard setting P2 1 /n for α-Yb); whereas the second polymorph, β, crystallizes in P$\bar{1}$. While the geometries of the molecules only vary slightly, the molecular packing and intramolecular contacts are quite different. In the structure of β, π–π interactions between the benzo- moieties of adjacent molecules are observed, whereas these interactions are absent in α. Despite the similarities in these classically 4f n+1 lanthanide systems, the complexes display distinct spectroscopic features in their respective absorption and photoluminescence spectra. Broadband 5d → 4f photoluminescence was observed for the Sm and Eu compounds in the NIR region and UV–visible region, respectively. None of the three Yb compounds exhibit photoluminescence UV–visible-NIR region; however, a unique photooxidation event was observed resulting in characteristic Yb(III) 4f → 4f transitions in the NIR region of the absorption spectra of these compounds. Finally, these findings are discussed along with structural comparisons of the 18-crown-6 and benzo-18-crown-6 compounds as well as other reported Ln(II) crown complexes in the literature.

crystals↗
DOE OSTI2021

Anharmonicity in partially filled skutterudites Yb x Co 4 Sb 12

Here, we report an experimental investigation of Yb filler ion dynamics in partially filled skutterudite samples Yb x Co 4 Sb 12 ( x = 0.26 and x = 0.4). From extended x-ray absorption fine structure (EXAFS) measurements at the Yb L 2 -edge, the mean-square displacements of the Yb fillers were extracted over a wide temperature range from 10 to 500 K. We found that the low-temperature dynamics of Yb fillers are described well using a harmonic oscillator approximation with Einstein temperatures of 70 ± 5 K for both samples. This finding is consistent with the observed low-energy phonon mode at 5.3(5) meV in the inelastic x-ray scattering (IXS) data. However, the temperature dependence deviates from the harmonic approximation at high temperatures due to significant cubic anharmonicity, which was revealed in the EXAFS cumulant analysis. Our study also demonstrates that complementary information on filler dynamics in skutterudites can be acquired using EXAFS and IXS.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Local rare-earth dopant structure in a complex-oxide/semiconductor heterojunction: Molecular beam epitaxy grown Yb-doped SrTiO3 on Si(001)

We have investigated the structural and electronic properties of Yb-doped SrTiO3/Si(001) grown by molecular beam epitaxy. Other rare-earth donor dopants that result in n-type conductivity typically substitute for Sr at the A-sites in the perovskite lattice. In contrast, Yb has been found to substitute predominantly for Ti at the perovskite B-sites based on data from atomically resolved scanning transmission electron microscopy and spectroscopy, as well as extended x-ray absorption fine structure. Yb exhibits two distinct charge states as determined by x-ray absorption spectroscopy and associated modeling, +2.7 and +2.1. These aliovalent substitutional dopants are compensated by donor electrons from oxygen vacancies that form during epitaxial film growth. An atom beam flux mismatch was present during film depositions because it was assumed that Yb would occupy A-sites, leading to a flux matching formula given by Yb + Sr = Ti. However, the formation of YbTi rather than YbSr results in Sr vacancies and extraneous (i.e. non-lattice) Ti atoms in the films, or on the film surfaces. The presence of these defects, together with oxygen vacancies, leads to deep-level electron traps that were detected by resonant photoemission and much higher sheet resistance than that associated with, for instance, La-doped films.

Chambers, Scott A. (ORCID:000000025415043X)↗
NASA NTRS2020

Structural evolution, electrochemical kinetic properties, and stability of A-site doped perovskite Sr(1-x)Yb(x)CoO(3-δ)

Mixed ionic and electronic conducting (MIEC) perovskite SrCoO(3-δ) is a widely studied (electro)catalyst for the oxygen reduction reaction (ORR) and possesses different crystal structures at different temperatures. These temperature dependent phase transitions significantly impact the ordering of oxygen vacancies and electrochemical kinetic properties as well as the reliability of the related devices. Some of the crystal structures formed, e.g. hexagonal phases, turn out to be almost impermeable to oxygen gas. Therefore, it is important to stabilize the crystal structure of SrCoO(3-δ) that favors the ORR over a wide temperature range. Herein, the partial substitution of the A-site Sr with Yb is systematically studied, including synthesis, characterization and analysis of structural evolution, electrochemical kinetic properties, thermal stability, and stability in a CO2-containing atmosphere. The results indicate that Sr(0.90)Yb(0.10)CoO(3-δ) is able to stabilize the tetragonal crystal structure with less ordered oxygen vacancies, leading to polarization resistances of 0.051, 0.115 and 0.272 U sq.cm at 750, 700 and 650 °C, respectively, on symmetrical cells. Sr(0.90)Yb(0.10)CoO(3-δ) demonstrates a very stable surface oxygen vacancy distribution and electronic structure near oxygen vacancies but dissociation of adsorbed oxygen molecules into atomic oxygen is affected by surface Sr segregation, and polarization resistance degradation is mainly induced by surface Sr segregation. Furthermore, Sr(0.90)Yb(0.10)CoO(3-δ) exhibits excellent thermal stability as well as excellent recovery stability and improved polarization performance after a few pure air/CO2-containing air treatment cycles at 700 °C. However, a hysteresis behavior of polarization performance is observed at 650 °C during gas cycling treatment, which may cause long-term degradation of the Sr(0.90)Yb(0.10)CoO(3-δ) electrode. The different polarization behaviors during gas cycling treatment are induced by different sensitivities of the formed surface strontium carbonate and chemisorbed surface oxo-carbonaceous species to different operating temperatures.

electrochemical kinetic↗
DOE OSTI2020

Materials Data on Yb(GaS2)2 by Materials Project

Yb(GaS2)2 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. there are three inequivalent Yb2+ sites. In the first Yb2+ site, Yb2+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Yb–S bond distances ranging from 2.97–3.07 Å. In the second Yb2+ site, Yb2+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are four shorter (2.99 Å) and four longer (3.05 Å) Yb–S bond lengths. In the third Yb2+ site, Yb2+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are four shorter (3.00 Å) and four longer (3.03 Å) Yb–S bond lengths. There are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four S2- atoms to form a mixture of corner and edge-sharing GaS4 tetrahedra. There are a spread of Ga–S bond distances ranging from 2.27–2.32 Å. In the second Ga3+ site, Ga3+ is bonded to four S2- atoms to form a mixture of corner and edge-sharing GaS4 tetrahedra. There are a spread of Ga–S bond distances ranging from 2.27–2.32 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to two Yb2+ and two equivalent Ga3+ atoms. In the second S2- site, S2- is bonded to two Yb2+ and two Ga3+ atoms to form a mixture of distorted corner and edge-sharing SYb2Ga2 trigonal pyramids. In the third S2- site, S2- is bonded in a 4-coordinate geometry to two Yb2+ and two equivalent Ga3+ atoms. In the fourth S2- site, S2- is bonded in a 4-coordinate geometry to two Yb2+ and two Ga3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb(PO3)3 by Materials Project

Yb(PO3)3 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. there are three inequivalent Yb3+ sites. In the first Yb3+ site, Yb3+ is bonded to six O2- atoms to form YbO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Yb–O bond distances ranging from 2.26–2.33 Å. In the second Yb3+ site, Yb3+ is bonded to six equivalent O2- atoms to form YbO6 octahedra that share corners with six equivalent PO4 tetrahedra. All Yb–O bond lengths are 2.29 Å. In the third Yb3+ site, Yb3+ is bonded to six equivalent O2- atoms to form YbO6 octahedra that share corners with six equivalent PO4 tetrahedra. All Yb–O bond lengths are 2.34 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two YbO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 3–21°. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two YbO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 30–32°. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent YbO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 10–27°. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent YbO6 octahedra and corners with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 28–43°. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to one Yb3+ and one P5+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Yb3+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the fifth O2- site, O2- is bonded in a linear geometry to one Yb3+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Yb3+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one Yb3+ and one P5+ atom. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to one Yb3+ and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Yb3+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a bent 150 degrees geometry to one Yb3+ and one P5+ atom. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb(Al10Cr)2 by Materials Project

YbCr2Al20 crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Yb is bonded in a 4-coordinate geometry to sixteen Al atoms. There are four shorter (3.13 Å) and twelve longer (3.20 Å) Yb–Al bond lengths. Cr is bonded to twelve Al atoms to form CrAl12 cuboctahedra that share corners with six equivalent CrAl12 cuboctahedra, edges with eighteen equivalent AlYbAl10Cr cuboctahedra, and faces with six equivalent AlYbAl10Cr cuboctahedra. There are six shorter (2.56 Å) and six longer (2.79 Å) Cr–Al bond lengths. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 12-coordinate geometry to two equivalent Cr and ten Al atoms. There are a spread of Al–Al bond distances ranging from 2.70–2.83 Å. In the second Al site, Al is bonded in a distorted linear geometry to two equivalent Yb and twelve equivalent Al atoms. All Al–Al bond lengths are 3.09 Å. In the third Al site, Al is bonded to one Yb, one Cr, and ten Al atoms to form distorted AlYbAl10Cr cuboctahedra that share corners with fifteen equivalent AlYbAl10Cr cuboctahedra, edges with two equivalent AlYbAl10Cr cuboctahedra, edges with three equivalent CrAl12 cuboctahedra, a faceface with one CrAl12 cuboctahedra, and faces with fifteen equivalent AlYbAl10Cr cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.71–2.91 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Molecular insights into Yb(III) speciation in sulfate-bearing hydrothermal fluids from X-ray absorption spectra informed by ab initio molecular dynamics

Rare earth elements (REEs) are critical for advanced technologies, yet in hydrothermal aqueous solutions the molecular level details of their interaction with ligands that control their geochemical transport and deposition remain poorly understood. Here, this study elucidates the coordination behavior of Yb 3+ in sulfate-rich hydrothermal fluids using in situ extended X-ray absorption fine structure (EXAFS) spectroscopy and ab initio molecular dynamics (AIMD) simulations. By integrating multi-angle EXAFS with AIMD-derived constraints, we precisely resolve Yb 3+ coordination structures and ligand interactions under hydrothermal conditions. At room temperature, Yb 3+ is coordinated by five water molecules and two sulfate ligands (coordination number, CN = 8), forming a distorted square antiprism geometry. Increasing temperature induces progressive dehydration, reducing the hydration shell and favoring stronger sulfate complexation. At 200°C, sulfate ligands reorganize around Yb 3+ , shifting its geometry to a capped octahedron (CN = 7). At 300 °C, sulfate binding dominates, leading to structural reorganization that parallels the onset of sulfate mineral precipitation, consistent with the retrograde solubility of REE sulfates. These findings provide direct molecular-scale evidence that sulfate acts as both a transport and deposition ligand, critically influencing REE mobility in geochemical environments. Our results can also help to refine thermodynamic models of REE speciation in high-temperature hydrothermal fluids and improve our understanding of REE ore formation processes in nature.

AIMD↗
DOE OSTI2021

Simultaneous Targeting of RSK and AKT Efficiently Inhibits YB-1-Mediated Repair of Ionizing Radiation-Induced DNA Double-Strand Breaks in Breast Cancer Cells

Y-box binding protein 1 (YB-1) overexpression is associated with chemotherapy- and radiation therapy resistance. Ionizing radiation (IR), receptor tyrosine kinase ligands, and mutation in KRAS gene stimulate activation of YB-1. YB-1 accelerates the repair of IR-induced DNA double-strand breaks (DSBs). Ribosomal S6 kinase (RSK) is the main kinase inducing YB-1 phosphorylation. We investigated the impact of RSK targeting on DSB repair and radiosensitivity.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2023

Distributive Nd-to-Yb Energy Transfer within Pure [YbNdYb] Heterometallic Molecules

Facile access to site-selective hetero-lanthanide molecules will open new avenues in the search of novel photophysical phenomena based on Ln-to-Ln' energy transfer (ET). This challenge demands strategies to segregate efficiently different Ln metal ions among different positions in a molecule. We report here the one-step synthesis and structure of a pure [YbNdYb] (1) coordination complex featuring short Yb···Nd distances, ideal to investigate a potential distributive (i.e., from one donor to two acceptors) intramolecular ET from one Nd 3+ ion to two Yb 3+ centers within a well-characterized molecule. The difference in ionic radius is the mechanism allowing to allocate selectively both types of metal ion within the molecular structure, exploited with the simultaneous use of two β-diketone-type ligands. To assist the photophysical investigation of this heterometallic species, the analogues [YbLaYb] (2) and [LuNdLu] (3) have also been prepared. Sensitization of Yb 3+ and Nd 3+ in the last two complexes, respectively, was observed, with remarkably long decay times, facilitating the determination of the Nd-to-Yb ET within the [YbNdYb] composite. This ET was demonstrated by comparing the emission of iso-absorbant solutions of 1, 2, and 3 and through lifetime determinations in solution and solid state. The comparatively high efficiency of this process corroborates the facilitating effect of having two acceptors for the nonradiative decay of Nd 3+ created within the [YbNdYb] molecule.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Isomeric states in the neutron-rich 𝑁 = 108 nuclei 178 Yb and 179 Lu

A multinucleon transfer reaction with a 136 Xe beam and a gold-backed 176 Yb target populated isomers in N = 108 178 Yb and 179 Lu. The single decay from the t 1/2 = 203(16) ns isomer in 178 Yb to the I π = 4 + level in the ground-state band suggests a I π = 4 − assignment, and multiquasiparticle calculations associate this state with the K π = 4 − , ν 2 (1/2[510], 9/2[624]) configuration. At least two isomers were observed in 179 Lu. One likely couples the K π = 4 − configuration found in 178 Yb to the 9/2[514] quasiproton orbital to form a K π = 17/2 + level (t 1/2 = 1.0(4) µs) which primarily decays into the rotational band based on the 9/2[514] state. A second isomer was observed to decay into this same band, but at higher energy and spin. Based on its feeding pattern, its similarity to an isomer found in 181 Ta, and a multiquasiparticle calculation, it is proposed to correspond to a K π = 29/2 − state based on the π9/2[514]ν 2 (9/2[624], 11/2[615]) configuration. As a result, an analysis of the reduced hindrance factors for negative-parity, two-quasineutron isomers in the rare-earth region is presented as well.

150 ≤ A ≤ 189↗
DOE OSTI2020

Materials Data on Yb(MnGe)2 by Materials Project

YbMn2Ge2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Yb is bonded in a 8-coordinate geometry to eight equivalent Ge atoms. All Yb–Ge bond lengths are 3.11 Å. Mn is bonded to four equivalent Ge atoms to form a mixture of edge and corner-sharing MnGe4 tetrahedra. All Mn–Ge bond lengths are 2.43 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Yb, four equivalent Mn, and one Ge atom. The Ge–Ge bond length is 2.65 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb(AlGe)2 by Materials Project

YbAl2Ge2 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Yb is bonded to six equivalent Ge atoms to form YbGe6 octahedra that share corners with twelve equivalent AlGe4 tetrahedra, edges with six equivalent YbGe6 octahedra, and edges with six equivalent AlGe4 tetrahedra. All Yb–Ge bond lengths are 3.01 Å. Al is bonded to four equivalent Ge atoms to form AlGe4 tetrahedra that share corners with six equivalent YbGe6 octahedra, corners with six equivalent AlGe4 tetrahedra, edges with three equivalent YbGe6 octahedra, and edges with three equivalent AlGe4 tetrahedra. The corner-sharing octahedra tilt angles range from 18–53°. There are three shorter (2.55 Å) and one longer (2.66 Å) Al–Ge bond lengths. Ge is bonded to three equivalent Yb and four equivalent Al atoms to form a mixture of distorted corner and edge-sharing GeYb3Al4 pentagonal bipyramids.

36 MATERIALS SCIENCE↗