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At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Th(FeGe)2 by Materials Project

Th(FeGe)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th is bonded in a 8-coordinate geometry to eight equivalent Fe and eight equivalent Ge atoms. All Th–Fe bond lengths are 3.21 Å. All Th–Ge bond lengths are 3.21 Å. Fe is bonded in a 4-coordinate geometry to four equivalent Th and four equivalent Ge atoms. All Fe–Ge bond lengths are 2.35 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Th and four equivalent Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(GePt)2 by Materials Project

Th(PtGe)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th is bonded in a 8-coordinate geometry to eight equivalent Pt and eight equivalent Ge atoms. All Th–Pt bond lengths are 3.34 Å. All Th–Ge bond lengths are 3.36 Å. Pt is bonded in a 4-coordinate geometry to four equivalent Th and four equivalent Ge atoms. All Pt–Ge bond lengths are 2.54 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Th, four equivalent Pt, and one Ge atom. The Ge–Ge bond length is 2.47 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(GeRh)2 by Materials Project

Th(RhGe)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th is bonded in a 8-coordinate geometry to eight equivalent Rh and eight equivalent Ge atoms. All Th–Rh bond lengths are 3.35 Å. All Th–Ge bond lengths are 3.24 Å. Rh is bonded to four equivalent Th and four equivalent Ge atoms to form a mixture of distorted edge, corner, and face-sharing RhTh4Ge4 tetrahedra. All Rh–Ge bond lengths are 2.49 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Th, four equivalent Rh, and one Ge atom. The Ge–Ge bond length is 2.54 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(Al2Cr)4 by Materials Project

ThCr4Al8 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th is bonded in a 12-coordinate geometry to eight equivalent Cr and twelve Al atoms. All Th–Cr bond lengths are 3.43 Å. There are four shorter (3.11 Å) and eight longer (3.22 Å) Th–Al bond lengths. Cr is bonded to two equivalent Th, two equivalent Cr, and eight Al atoms to form distorted CrTh2Al8Cr2 cuboctahedra that share corners with eight equivalent AlTh2Al6Cr4 cuboctahedra, corners with ten equivalent CrTh2Al8Cr2 cuboctahedra, edges with four equivalent CrTh2Al8Cr2 cuboctahedra, edges with four equivalent AlTh2Al6Cr4 cuboctahedra, faces with six equivalent CrTh2Al8Cr2 cuboctahedra, and faces with eight equivalent AlTh2Al6Cr4 cuboctahedra. Both Cr–Cr bond lengths are 2.51 Å. There are four shorter (2.59 Å) and four longer (2.72 Å) Cr–Al bond lengths. There are two inequivalent Al sites. In the first Al site, Al is bonded to two equivalent Th, four equivalent Cr, and six Al atoms to form distorted AlTh2Al6Cr4 cuboctahedra that share corners with eight equivalent CrTh2Al8Cr2 cuboctahedra, corners with ten equivalent AlTh2Al6Cr4 cuboctahedra, edges with three equivalent AlTh2Al6Cr4 cuboctahedra, edges with four equivalent CrTh2Al8Cr2 cuboctahedra, faces with seven equivalent AlTh2Al6Cr4 cuboctahedra, and faces with eight equivalent CrTh2Al8Cr2 cuboctahedra. There are two shorter (2.74 Å) and four longer (2.86 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a 10-coordinate geometry to one Th, four equivalent Cr, and five Al atoms. The Al–Al bond length is 2.80 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(NiGe)2 by Materials Project

Th(NiGe)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th is bonded in a 8-coordinate geometry to eight equivalent Ni and eight equivalent Ge atoms. All Th–Ni bond lengths are 3.21 Å. All Th–Ge bond lengths are 3.22 Å. Ni is bonded in a 4-coordinate geometry to four equivalent Th and four equivalent Ge atoms. All Ni–Ge bond lengths are 2.39 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Th, four equivalent Ni, and one Ge atom. The Ge–Ge bond length is 2.57 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(SiRh)2 by Materials Project

Th(RhSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th is bonded in a 8-coordinate geometry to eight equivalent Rh and eight equivalent Si atoms. All Th–Rh bond lengths are 3.28 Å. All Th–Si bond lengths are 3.17 Å. Rh is bonded to four equivalent Th and four equivalent Si atoms to form a mixture of distorted corner, edge, and face-sharing RhTh4Si4 tetrahedra. All Rh–Si bond lengths are 2.44 Å. Si is bonded in a 9-coordinate geometry to four equivalent Th, four equivalent Rh, and one Si atom. The Si–Si bond length is 2.46 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(CuGe)2 by Materials Project

Th(CuGe)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th is bonded in a 8-coordinate geometry to eight equivalent Cu and eight equivalent Ge atoms. All Th–Cu bond lengths are 3.29 Å. All Th–Ge bond lengths are 3.22 Å. Cu is bonded in a 4-coordinate geometry to four equivalent Th and four equivalent Ge atoms. All Cu–Ge bond lengths are 2.46 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Th, four equivalent Cu, and one Ge atom. The Ge–Ge bond length is 2.51 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(GeOs)2 by Materials Project

Th(OsGe)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th is bonded in a 8-coordinate geometry to eight equivalent Os and eight equivalent Ge atoms. All Th–Os bond lengths are 3.30 Å. All Th–Ge bond lengths are 3.31 Å. Os is bonded in a 4-coordinate geometry to four equivalent Th and four equivalent Ge atoms. All Os–Ge bond lengths are 2.48 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Th, four equivalent Os, and one Ge atom. The Ge–Ge bond length is 2.58 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(MoO4)2 by Materials Project

Th(MoO4)2 crystallizes in the hexagonal P-6 space group. The structure is three-dimensional. there are five inequivalent Th4+ sites. In the first Th4+ site, Th4+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are three shorter (2.39 Å) and six longer (2.48 Å) Th–O bond lengths. In the second Th4+ site, Th4+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Th–O bond distances ranging from 2.18–2.74 Å. In the third Th4+ site, Th4+ is bonded to seven O2- atoms to form distorted ThO7 pentagonal bipyramids that share corners with seven MoO4 tetrahedra. There are a spread of Th–O bond distances ranging from 2.36–2.44 Å. In the fourth Th4+ site, Th4+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are three shorter (2.41 Å) and six longer (2.45 Å) Th–O bond lengths. In the fifth Th4+ site, Th4+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are six shorter (2.42 Å) and three longer (2.47 Å) Th–O bond lengths. There are six inequivalent Mo6+ sites. In the first Mo6+ site, Mo6+ is bonded to four O2- atoms to form MoO4 tetrahedra that share corners with two equivalent ThO7 pentagonal bipyramids. There are a spread of Mo–O bond distances ranging from 1.76–1.82 Å. In the second Mo6+ site, Mo6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Mo–O bond distances ranging from 1.77–1.84 Å. In the third Mo6+ site, Mo6+ is bonded to four O2- atoms to form MoO4 tetrahedra that share corners with two equivalent ThO7 pentagonal bipyramids. There are a spread of Mo–O bond distances ranging from 1.76–1.83 Å. In the fourth Mo6+ site, Mo6+ is bonded to four O2- atoms to form MoO4 tetrahedra that share corners with two equivalent ThO7 pentagonal bipyramids. There are a spread of Mo–O bond distances ranging from 1.76–1.82 Å. In the fifth Mo6+ site, Mo6+ is bonded to four O2- atoms to form MoO4 tetrahedra that share a cornercorner with one ThO7 pentagonal bipyramid. There are a spread of Mo–O bond distances ranging from 1.76–1.89 Å. In the sixth Mo6+ site, Mo6+ is bonded in a tetrahedral geometry to four O2- atoms. There is three shorter (1.77 Å) and one longer (1.86 Å) Mo–O bond length. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to one Th4+ and one Mo6+ atom. In the second O2- site, O2- is bonded in a distorted linear geometry to one Th4+ and one Mo6+ atom. In the third O2- site, O2- is bonded in a water-like geometry to one Th4+ and one Mo6+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to one Th4+ and one Mo6+ atom. In the fifth O2- site, O2- is bonded in a distorted linear geometry to one Th4+ and one Mo6+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Th4+ and one Mo6+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Th4+ and one Mo6+ atom. In the eighth O2- site, O2- is bonded in a linear geometry to one Th4+ and one Mo6+ atom. In the ninth O2- site, O2- is bonded in a distorted linear geometry to one Th4+ and one Mo6+ atom. In the tenth O2- site, O2- is bonded in a single-bond geometry to one Mo6+ atom. In the eleventh O2- site, O2- is bonded in a distorted single-bond geometry to one Th4+ and one Mo6+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to one Th4+ and one Mo6+ atom. In the thirteenth O2- site, O2- is bonded in a water-like geometry to one Th4+ and one Mo6+ atom. In the fourteenth O2- site, O2- is bonded in a distorted water-like geometry to one Th4+ and one Mo6+ atom. In the fifteenth O2- site, O2- is bonded in a distorted linear geometry to one Th4+ and one Mo6+ atom. In the sixteenth O2- site, O2- is bonded in a 2-coordinate geometry to one Th4+ and one Mo6+ atom. In the seventeenth O2- site, O2- is bonded in a single-bond geometry to one Mo6+ atom. In the eighteenth O2- site, O2- is bonded in a single-bond geometry to one Mo6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(BRu)2 by Materials Project

Th(RuB)2 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. Th is bonded in a 10-coordinate geometry to four equivalent Ru and six equivalent B atoms. All Th–Ru bond lengths are 3.02 Å. There are two shorter (2.88 Å) and four longer (3.08 Å) Th–B bond lengths. Ru is bonded in a 4-coordinate geometry to two equivalent Th and four equivalent B atoms. There are two shorter (2.09 Å) and two longer (2.16 Å) Ru–B bond lengths. B is bonded in a 7-coordinate geometry to three equivalent Th and four equivalent Ru atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(BRh)4 by Materials Project

Th(RhB)4 crystallizes in the tetragonal P4_2/nmc space group. The structure is three-dimensional. Th is bonded in a 12-coordinate geometry to twelve equivalent Rh and twelve equivalent B atoms. There are four shorter (3.03 Å) and eight longer (3.21 Å) Th–Rh bond lengths. There are eight shorter (3.07 Å) and four longer (3.21 Å) Th–B bond lengths. Rh is bonded in a 5-coordinate geometry to three equivalent Th and five equivalent B atoms. There are a spread of Rh–B bond distances ranging from 2.24–2.31 Å. B is bonded in a 6-coordinate geometry to three equivalent Th, five equivalent Rh, and one B atom. The B–B bond length is 1.79 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(Mg4Al3)4 by Materials Project

Th(Mg4Al3)4 is alpha-derived structured and crystallizes in the cubic I-43m space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a 10-coordinate geometry to three equivalent Mg, one Th, and six equivalent Al atoms. All Mg–Mg bond lengths are 3.02 Å. The Mg–Th bond length is 3.36 Å. All Mg–Al bond lengths are 3.23 Å. In the second Mg site, Mg is bonded in a 12-coordinate geometry to seven Mg and five equivalent Al atoms. There are two shorter (3.11 Å) and four longer (3.18 Å) Mg–Mg bond lengths. There are a spread of Mg–Al bond distances ranging from 2.85–3.19 Å. Th is bonded in a 12-coordinate geometry to four equivalent Mg and twelve equivalent Al atoms. All Th–Al bond lengths are 3.25 Å. Al is bonded in a 11-coordinate geometry to seven Mg, one Th, and three equivalent Al atoms. There are one shorter (2.74 Å) and two longer (2.80 Å) Al–Al bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Preliminary Insights Into the Feasibility of Determining the Purification Date of Enriched Uranium by Direct Measurement of the 230 Th/ 234 U Ratio Using an All-Faraday Detector Configuration on the Neoma MC-ICP-MS

Rationale: Mass spectrometric measurement of the 230 Th/ 234 U ratio to calculate the purification age of enriched uranium is typically conducted via a combination of ion counters and faraday detectors, thus requiring an inter-detector calibration scheme. Here, our aim is to understand whether the pursuit of a simplified measurement scheme involving only faraday detectors is feasible. Methods: We investigate the possibility of determining U-Th model ages for two enriched uranium standards (NBL U630 and U850) by direct measurement of the 230 Th/ 234 U ratio (without chromatographic separation or isotope dilution) on a ThermoFisher Scientific Neoma MC-ICP-MS utilizing both solution and laser ablation (LA)-based sampling techniques and an all-faraday detector configuration. Results: For the solution mode analyses conducted on aliquots containing sub μg/mL total U, we produce composite average 230 Th/ 234 U model dates of May 19, 1988 (± 351 days), and March 26, 1961 (± 2.5 years) using the directly measured 230 Th/ 234 U ratios for the NBL U630 and U850 uranium standards, which have certified purification dates of June 6, 1988 (± 190 days), and December 31, 1957 (± 36.5 days), respectively. The ages produced by LA-based sampling of dried residues of the same standards deposited onto cotton TexWipes are less accurate and of poorer precision (June 23, 2004 ± 8.7 years for U630 and December 21, 1965 ± 7.9 years for U850) but still yield meaningful information in regards to the purification date. Conclusions: We believe that further refinement of the all faraday detector measurement approach to include development of a more robust Th/U relative sensitivity factor determination, signal cutoff selection, and data processing protocols will allow for this approach to be confidently applied to enriched uranium materials with unknown purification histories. Potential advantages of the method include the reduced sample handling and infrastructure requirements as well as the ability to simultaneously generate a broad picture of the uranium isotopic composition in tandem with the U-Th age determination.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2026

Irradiation Driven Restructuring of Nanocrystalline ThO 2 and Th 1–x U x O 2 Thin Films

Irradiation induced structural changes of actinide oxide materials is a key consideration in their development and use as nuclear fuels. This study reported on the synthesis of ThO 2 and Th 1–x U x O 2 (x = 0.15, 0.50) thin films, fabricated using electrospray-assisted solution combustion synthesis, and their responses to ion irradiation. Krypton ion irradiations, up to a fluence of 1 × 10 16 ions/cm 2 , were carried out to simulate radiation damage induced by fission products in a reactor environment. Structural and chemical changes induced by irradiation were analyzed using high-resolution scanning transmission electron microscopy (STEM), energy-dispersive X-ray spectroscopy (EDS), and electron energy-loss spectroscopy (EELS). It was determined that the extent and nature of irradiation-induced damage are strongly correlated with the uranium content. ThO 2 films were most susceptible to radiation-induced damage, with significant cavity formation and delamination from the substrate at high fluence. Of the compositions studied, Th 0.85 U 0.15 O 2 films showed the highest stability, characterized by moderate grain growth and the absence of voids or severe defect structures. In contrast, Th 0.5 U 0.5 O 2 films accumulated extensive damage, including the formation of a nanocrystalline central region. EELS analysis indicated that oxygen displacement is the primary driver of structural degradation in Th 0.5 U 0.5 O 2 films. α-particle spectroscopy confirmed minimal actinide loss across all compositions, underscoring the mechanical robustness of the films. These findings provide insight into the irradiation-induced damage mechanisms in Th O2 and Th 1–x U x O 2 systems, supporting their development as potential materials for nuclear fuels and irradiation-tolerant thin film targets in nuclear physics measurements.

Th1−xUxO2↗
DOE OSTI2022

Developing a Th Resonance Ionization Scheme: for Future Use in Age Dating SNM by Resonance Ionization Mass Spectrometry

We report the development of a Th resonance ionization scheme (RIS) for analyzing Th isotopes by resonance ionization mass spectrometry (RIMS) to enable age-dating via the 230 Th/ 234 U inter-elemental pair. This report summarizes the work that completes the first of two tasks that are required for developing U-Th dating via RIMS at the Laser Ionization of Neutrals (LION) laboratory at Lawrence Livermore National Laboratory (LLNL). The first task involves choosing and vetting an appropriate Th RIS for the LION instrument and simultaneous U and Th analysis.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2020

Materials Data on Th(CrGe)2 by Materials Project

ThCr2Ge2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th is bonded in a 8-coordinate geometry to eight equivalent Cr and eight equivalent Ge atoms. All Th–Cr bond lengths are 3.38 Å. All Th–Ge bond lengths are 3.23 Å. Cr is bonded to four equivalent Th and four equivalent Ge atoms to form a mixture of edge, face, and corner-sharing CrTh4Ge4 tetrahedra. All Cr–Ge bond lengths are 2.48 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Th, four equivalent Cr, and one Ge atom. The Ge–Ge bond length is 2.63 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(CoGe)2 by Materials Project

ThCo2Ge2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th is bonded in a 8-coordinate geometry to eight equivalent Co and eight equivalent Ge atoms. All Th–Co bond lengths are 3.21 Å. All Th–Ge bond lengths are 3.22 Å. Co is bonded in a 4-coordinate geometry to four equivalent Th and four equivalent Ge atoms. All Co–Ge bond lengths are 2.37 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Th, four equivalent Co, and one Ge atom. The Ge–Ge bond length is 2.63 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(GePd)2 by Materials Project

ThPd2Ge2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th is bonded in a 8-coordinate geometry to eight equivalent Pd and eight equivalent Ge atoms. All Th–Pd bond lengths are 3.36 Å. All Th–Ge bond lengths are 3.30 Å. Pd is bonded in a 4-coordinate geometry to four equivalent Th and four equivalent Ge atoms. All Pd–Ge bond lengths are 2.54 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Th, four equivalent Pd, and one Ge atom. The Ge–Ge bond length is 2.48 Å.

36 MATERIALS SCIENCE↗