Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Tm”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Tm(HO)3 by Materials Project

Tm(HO)3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Tm3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Tm–O bond distances ranging from 2.36–2.67 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to three equivalent Tm3+ and one H1+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to three equivalent Tm3+ and one H1+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to three equivalent Tm3+ and one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tm(HO)3 by Materials Project

Tm(HO)3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. Tm3+ is bonded in a 9-coordinate geometry to nine equivalent O2- atoms. There are six shorter (2.37 Å) and three longer (2.47 Å) Tm–O bond lengths. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. O2- is bonded in a single-bond geometry to three equivalent Tm3+ and one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tm(CuO2)2 by Materials Project

Tm(CuO2)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Tm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are six shorter (2.35 Å) and two longer (2.37 Å) Tm–O bond lengths. There are two inequivalent Cu+2.50+ sites. In the first Cu+2.50+ site, Cu+2.50+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.88 Å) and two longer (1.89 Å) Cu–O bond length. In the second Cu+2.50+ site, Cu+2.50+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.91 Å) and two longer (1.93 Å) Cu–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Tm3+ and two Cu+2.50+ atoms to form a mixture of distorted corner and edge-sharing OTm2Cu2 tetrahedra. In the second O2- site, O2- is bonded to two equivalent Tm3+ and two Cu+2.50+ atoms to form a mixture of distorted corner and edge-sharing OTm2Cu2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tm(AlC)3 by Materials Project

Tm(AlC)3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Tm3+ is bonded to six equivalent C4- atoms to form TmC6 octahedra that share corners with six equivalent AlC4 tetrahedra, edges with six equivalent TmC6 octahedra, and edges with six equivalent AlC4 tetrahedra. All Tm–C bond lengths are 2.52 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four C4- atoms to form AlC4 tetrahedra that share corners with three equivalent TmC6 octahedra, corners with seven equivalent AlC4 tetrahedra, and edges with three equivalent TmC6 octahedra. The corner-sharing octahedral tilt angles are 19°. There are one shorter (2.02 Å) and three longer (2.10 Å) Al–C bond lengths. In the second Al3+ site, Al3+ is bonded in a trigonal planar geometry to three equivalent C4- atoms. All Al–C bond lengths are 1.97 Å. There are two inequivalent C4- sites. In the first C4- site, C4- is bonded to three equivalent Tm3+ and three equivalent Al3+ atoms to form distorted CTm3Al3 octahedra that share corners with three equivalent CTm3Al3 octahedra, corners with three equivalent CAl5 trigonal bipyramids, and edges with nine equivalent CTm3Al3 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second C4- site, C4- is bonded to five Al3+ atoms to form CAl5 trigonal bipyramids that share corners with six equivalent CTm3Al3 octahedra and corners with six equivalent CAl5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 70°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tm(Co2B)6 by Materials Project

Tm(Co2B)6 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Tm3+ is bonded in a hexagonal planar geometry to six equivalent B3- atoms. All Tm–B bond lengths are 3.03 Å. There are two inequivalent Co+1.25+ sites. In the first Co+1.25+ site, Co+1.25+ is bonded in a T-shaped geometry to three equivalent B3- atoms. All Co–B bond lengths are 2.10 Å. In the second Co+1.25+ site, Co+1.25+ is bonded to four equivalent B3- atoms to form a mixture of distorted edge and corner-sharing CoB4 trigonal pyramids. There are two shorter (2.02 Å) and two longer (2.04 Å) Co–B bond lengths. B3- is bonded in a 7-coordinate geometry to one Tm3+ and seven Co+1.25+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tm(CuS)3 by Materials Project

Tm(CuS)3 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Tm3+ is bonded to six equivalent S2- atoms to form TmS6 octahedra that share corners with twelve equivalent CuS4 tetrahedra, edges with three equivalent TmS6 octahedra, and edges with six equivalent CuS4 tetrahedra. There are three shorter (2.70 Å) and three longer (2.71 Å) Tm–S bond lengths. Cu1+ is bonded to four equivalent S2- atoms to form CuS4 tetrahedra that share corners with four equivalent TmS6 octahedra, corners with six equivalent CuS4 tetrahedra, edges with two equivalent TmS6 octahedra, and edges with three equivalent CuS4 tetrahedra. The corner-sharing octahedra tilt angles range from 16–55°. There are a spread of Cu–S bond distances ranging from 2.33–2.41 Å. S2- is bonded to two equivalent Tm3+ and four equivalent Cu1+ atoms to form a mixture of distorted edge and corner-sharing STm2Cu4 octahedra. The corner-sharing octahedra tilt angles range from 0–90°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tm(BRu)4 by Materials Project

Tm(RuB)4 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional. Tm3+ is bonded in a 12-coordinate geometry to twelve equivalent B3- atoms. There are a spread of Tm–B bond distances ranging from 2.96–3.21 Å. Ru+2.25+ is bonded to five equivalent B3- atoms to form a mixture of distorted edge and corner-sharing RuB5 trigonal bipyramids. There are a spread of Ru–B bond distances ranging from 2.15–2.28 Å. B3- is bonded in a 6-coordinate geometry to three equivalent Tm3+, five equivalent Ru+2.25+, and one B3- atom. The B–B bond length is 1.79 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tm(Mo3Se4)2 by Materials Project

Tm(Mo3Se4)2 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Tm3+ is bonded in a body-centered cubic geometry to eight Se2- atoms. There are two shorter (2.78 Å) and six longer (3.08 Å) Tm–Se bond lengths. Mo+2.17+ is bonded to five Se2- atoms to form a mixture of edge and corner-sharing MoSe5 square pyramids. There are a spread of Mo–Se bond distances ranging from 2.54–2.74 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 1-coordinate geometry to one Tm3+ and three equivalent Mo+2.17+ atoms. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to one Tm3+ and four equivalent Mo+2.17+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tm(IO3)3 by Materials Project

Tm(O3I)3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Tm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Tm–O bond distances ranging from 2.23–2.56 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Tm3+ and one I5+ atom. The O–I bond length is 1.85 Å. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Tm3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one I5+ atom. The O–I bond length is 1.83 Å. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Tm3+ and one I5+ atom. The O–I bond length is 1.83 Å. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Tm3+ and one I5+ atom. The O–I bond length is 1.83 Å. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Tm3+ and one I5+ atom. The O–I bond length is 1.82 Å. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Tm3+ and one I5+ atom. The O–I bond length is 1.84 Å. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one Tm3+ and one I5+ atom. The O–I bond length is 1.83 Å. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to one Tm3+ and one I5+ atom. The O–I bond length is 1.82 Å. There are three inequivalent I5+ sites. In the first I5+ site, I5+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. In the second I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms. In the third I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Structure and thermodynamics of calcium rare earth silicate oxyapatites, Ca 2 RE 8 (SiO 4 ) 6 O 2 (RE = Pr, Tb, Ho, Tm)

Calcium rare earth silicate oxyapatites, (Ca 2 RE 8 (SiO 4 ) 6 O 2 ), are of interest as components of glass-ceramic nuclear waste forms. To assess their long-term behavior in a geologic repository, it is essential to determine their structure and thermodynamic stability at relevant conditions. Here, in this work, we performed detailed structural and thermodynamic investigations on Ca 2 Pr 8 (SiO 4 ) 6 O 2 , Ca 2 Tb 8 (SiO 4 ) 6 O 2 , Ca 2 Ho 8 (SiO 4 ) 6 O 2 , and Ca 2 Tm 8 (SiO 4 ) 6 O 2 by high energy synchrotron powder X-ray diffraction combined with Rietveld analysis and high temperature oxide melt drop solution calorimetry. Enthalpies of formation from constituent oxides (ΔH f,ox ) were determined to be -765.1 ± 22.8 kJ/mol for Ca 2 Pr 8 (SiO 4 ) 6 O 2 ; -638.9 ± 20.5 kJ/mol for Ca 2 Tb 8 (SiO 4 ) 6 O 2 ; -643.3 ± 10.3 kJ/mol for Ca 2 Ho 8 (SiO 4 ) 6 O 2 ; and -403.2 ± 5.1 kJ/mol for Ca 2 Tm 8 (SiO 4 ) 6 O 2 . These thermodynamic parameters were used in assessing the thermochemical stability of these phases in the presence of water vapor from room temperature to 600 K, as encountered in the subsurface environments of a geological repository.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Resistivity and magnetoresistance properties of R 2 NiSi 3 (R = Gd, Dy, Ho, Er, Tm) compounds

The resistivity and magnetoresistance behaviour of the hexagonal intermetallic compounds R 2 NiSi 3 (R = Gd, Dy, Ho, Er, and Tm) are reported here. All the studied polycrystalline compounds exhibit metallic behavior along with additional magnetic anomalies at low temperatures. A well-defined resistivity minima is observed in Gd 2 NiSi 3 and Dy 2 Ni 0.87 Si 2.95 at a temperature much higher than their respective magnetic transition temperatures. The anomaly has been ascribed to the charge carrier localization caused by magnetic precursor effect. Magnetic field induced crossover from positive to negative magnetoresistance (MR) behavior associated with antiferromagnetic ground state is evidenced for Gd 2 NiSi 3 and Er 2 NiSi 3 in the low temperature region. Although Tm 2 Ni 0.93 Si 2.93 does not exhibit any long range magnetic order down to 2 K, a sudden drop in resistivity behavior is observed below ~10 K. Furthermore, presence of short range magnetic correlation observed in a wide temperature range, much beyond their respective magnetic ordering temperatures, has been argued to be responsible for achieving finite negative MR for all the compounds. Additionally, a subtle resemblance between the observed transport anomalies and the magnetic properties of these systems has been discussed.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Enhanced long-term cyclability in Li-Rich layered oxides by electrochemically constructing a Li x TM 3-x O 4 -type spinel shell

The poor long-term cycling stability, including the fast capacity fade and the severe voltage decay, has become the main concern hindering the practical application of Li-rich layered oxides, a promising cathode for high- energy-density Li-ion battery. Herein, we design and electrochemically construct a ~10 nm-thick Li x TM 3-x O 4 - type (TM ¼Ni, Co, Mn, 0 3 O 4 -type spinel phase and the good Liþconductivity of LiMn 2 O 4 -type spinel phase. Systemic structural and electrochemical analysis demonstrate that, it slows down the activation rate of Li 2 MnO 3 component and efficiently alleviates the lattice O loss at high voltage (>4.5 V) and Mn dissolution, thereby suppressing the structural degradation from the layered phase to the spinel phase in the bulk, eventually significantly enhancing the long-term cycling stability. This study adds richness into the Mn-based spinel phase system and provides a new heterostructure design strategy to improve the electrochemical performance of Li-rich layered cathodes and beyond.

25 ENERGY STORAGE↗
DOE OSTI2025

Magnetic properties of Tm 3+ in layered triangular lattices

Rare-earth chalcogenides, ARCh 2 (A = alkali metal or monovalent ion; R = rare-earth elements; Ch = O, S, and Se), have been identified as promising candidates for exploring a variety of novel frustrated quantum magnetic phenomena. Tm-based series, ATmCh 2 , where Tm 3+ ions are arranged on various frustrated geometric lattices, provide a platform for investigating the competitions among spin–orbit coupling, crystal field effects, and magnetic exchange interactions in the context of geometric frustration. In this study, we present how the crystallographic structures of newly synthesized ATmSe 2 (A = Li and Na) influence their frustrated magnetic behaviors. Both NaTmSe 2 and LiTmSe 2 adopt a delafossite-type structure with a two-dimensional (2D) triangular lattice, but LiTmSe 2 has a much shorter c-axis parameter compared to this in NaTmSe 2 . Both heat capacity and magnetic susceptibility measurements confirm the absence of long-range magnetic order in either compound. However, magnetic measurements data reveals the differences in magnetic interactions: NaTmSe 2 exhibits features of low-dimensional magnetism, likely driven by its layered crystal structure, compared to LiTmSe 2 .

Crystal field theory↗
DOE OSTI2022

Fine structure in the odd-odd proton emitter Tm 144

Axial symmetry breaking in 144 Tm is probed by examining its proton emission fine structure. The ground-state spin and parity in 144 Tm and daughter 143 Er are assigned unambiguously based on the corroboration of our calculations with the present data. Here we establish the first microscopic description of fine structure in odd-odd proton emitters, which is capable of resolving ambiguities present in the assignments of transitions in such nuclei.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2024

Synthesis and characterization of the novel breathing pyrochlore compound Ba 3 ⁢Tm 2⁢ Zn 5⁢ O 11

In this study, a novel material from the rare-earth based breathing pyrochlore family, Ba 3 ⁢Tm 2 ⁢Zn 5 ⁢O 11 , was successfully synthesized. Powder x-ray diffraction and high-resolution powder neutron diffraction confirmed phase purity and the $F\bar4$3⁢𝑚 breathing pyrochlore crystal structure, while thermogravimetric analysis revealed incongruent melting behavior compared to its counterpart, Ba 3 ⁢Yb 2⁢ Zn 5⁢ O 11 . High-quality single crystals of Ba 3 ⁢Tm 2 ⁢Zn 5 ⁢O 11 were grown using the traveling solvent floating zone technique and assessed using Laue x-ray diffraction and single crystal x-ray diffraction. Further, thermodynamic characterization indicated paramagnetic behavior down to 0.05 K, and inelastic neutron scattering measurements identified distinct dispersionless crystal electric field energy bands, with the fitted crystal electric field model predicting a single-ion singlet ground state and an energy gap of ∼9 meV separating it from the first excited (singlet) state. Additional low-energy excitation studies on single crystals revealed dispersionless bands at 0.8 and 1 meV. Computed phonon dispersions from first-principles calculations ruled out phonons as the origin of these modes, further illustrating the puzzling and unique properties of Ba 3 ⁢Tm⁢ 2 Zn 5 ⁢O 11 .

36 MATERIALS SCIENCE↗
DOE OSTI2022

1 GW peak power and 100 J pulsed operation of a diode-pumped Tm:YLF laser

We report on the generation of high energy, high power pulses in a tabletop diode-pumped Tm:YLF-based laser system, which delivers amplified pulse energies up to 108 J, as well as GW peak power performance when seeded with nanosecond duration pulses. Furthermore, the high power and efficiency capabilities of operating Tm:YLF in the multi-pulse extraction (MPE) regime were explored by seeding the experimental setup with a multi-kHz burst of pulses exhibiting a low individual pulse fluence, resulting in a 3.6 kW average power train of multi-joule-level pulses with an optical-to-optical efficiency of 19%.

47 OTHER INSTRUMENTATION↗
DOE OSTI2021

Demonstration of a compact, multi-joule, diode-pumped Tm:YLF laser

We report the demonstration of a diode-pumped Tm:YLF laser operating at 1.88 µm that produces pulse energies up to 3.88 J in 20 ns. The compact system consists of a Q-switched cavity-dumped oscillator generating 18 mJ pulses, which are then amplified in a 4-pass power amplifier. Energies up to 38.1 J were obtained with long-pulse amplifier operation. These results illustrate the high energy storage and extraction capabilities of diode-pumped Tm:YLF, opening the path to high peak and average power mid-infrared solid-state lasers

47 OTHER INSTRUMENTATION↗
DOE OSTI2024

Demonstration of a 1 TW peak power, joule-level ultrashort Tm:YLF laser

Here we report on the demonstration of a diode-pumped, Tm:YLF-based, chirped pulse amplification laser system operating at λ ≈ 1.9 µm that produces amplified pulse energies exceeding 1.5 J using a single 8-pass power amplifier. The amplified pulses are subsequently compressed to sub-300 fs durations by a diffraction grating pair, producing record >1 TW peak power pulses. To the best of our knowledge, this is the highest peak power demonstrated for any solid-state, near-2 µm laser architecture and illustrates the potential of Tm:YLF for the next generation of high-power, diode-pumped ultrashort lasers.

47 OTHER INSTRUMENTATION↗