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At least 1,459 records · Page 81
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on MgSn2 by Materials Project

MgSn2 crystallizes in the trigonal R32 space group. The structure is three-dimensional. Mg is bonded in a 12-coordinate geometry to nine Sn atoms. There are a spread of Mg–Sn bond distances ranging from 3.22–3.41 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded to six equivalent Mg and six equivalent Sn atoms to form a mixture of edge and corner-sharing SnMg6Sn6 cuboctahedra. All Sn–Sn bond lengths are 3.23 Å. In the second Sn site, Sn is bonded in a 12-coordinate geometry to four equivalent Mg and two equivalent Sn atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg6NiSn by Materials Project

Mg6NiSn crystallizes in the tetragonal P4_2cm space group. The structure is three-dimensional. there are five inequivalent Mg sites. In the first Mg site, Mg is bonded in a 2-coordinate geometry to two equivalent Ni and one Sn atom. There are one shorter (2.66 Å) and one longer (2.70 Å) Mg–Ni bond lengths. The Mg–Sn bond length is 3.11 Å. In the second Mg site, Mg is bonded in a 3-coordinate geometry to one Ni and two equivalent Sn atoms. The Mg–Ni bond length is 2.75 Å. There are one shorter (2.97 Å) and one longer (3.07 Å) Mg–Sn bond lengths. In the third Mg site, Mg is bonded in a distorted linear geometry to two equivalent Ni atoms. Both Mg–Ni bond lengths are 2.70 Å. In the fourth Mg site, Mg is bonded to four equivalent Sn atoms to form edge-sharing MgSn4 tetrahedra. There are two shorter (2.94 Å) and two longer (3.00 Å) Mg–Sn bond lengths. In the fifth Mg site, Mg is bonded in a distorted linear geometry to one Ni and one Sn atom. The Mg–Ni bond length is 2.55 Å. The Mg–Sn bond length is 2.90 Å. Ni is bonded in a 9-coordinate geometry to eight Mg and one Sn atom. The Ni–Sn bond length is 2.68 Å. Sn is bonded in a 10-coordinate geometry to nine Mg and one Ni atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y6Co2Sn by Materials Project

Y6Co2Sn crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are three inequivalent Y sites. In the first Y site, Y is bonded in a 4-coordinate geometry to two Co and two Sn atoms. There are one shorter (2.75 Å) and one longer (3.21 Å) Y–Co bond lengths. There are one shorter (3.09 Å) and one longer (3.35 Å) Y–Sn bond lengths. In the second Y site, Y is bonded in a 5-coordinate geometry to three Co and two Sn atoms. There are two shorter (2.95 Å) and one longer (3.20 Å) Y–Co bond lengths. There are one shorter (3.26 Å) and one longer (3.68 Å) Y–Sn bond lengths. In the third Y site, Y is bonded in a 4-coordinate geometry to three Co and one Sn atom. There are one shorter (2.77 Å) and two longer (2.89 Å) Y–Co bond lengths. The Y–Sn bond length is 3.44 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded in a 9-coordinate geometry to eight Y and one Co atom. The Co–Co bond length is 2.69 Å. In the second Co site, Co is bonded in a 9-coordinate geometry to eight Y and one Co atom. The Co–Co bond length is 2.24 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a cuboctahedral geometry to twelve Y atoms. In the second Sn site, Sn is bonded in a body-centered cubic geometry to eight Y atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ce2(CuSn)3 by Materials Project

Ce2(CuSn)3 crystallizes in the tetragonal P4/mmm space group. The structure is one-dimensional and consists of one Ce2(CuSn)3 ribbon oriented in the (0, 0, 1) direction. Ce is bonded in a linear geometry to one Cu and one Sn atom. The Ce–Cu bond length is 2.62 Å. The Ce–Sn bond length is 2.93 Å. There are two inequivalent Cu sites. In the first Cu site, Cu is bonded in a linear geometry to one Ce and one Sn atom. The Cu–Sn bond length is 2.47 Å. In the second Cu site, Cu is bonded in a linear geometry to two equivalent Sn atoms. Both Cu–Sn bond lengths are 2.47 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a linear geometry to one Ce and one Cu atom. In the second Sn site, Sn is bonded in a linear geometry to two equivalent Cu atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSn2 by Materials Project

MgSn2 crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Mg is bonded to nine Sn atoms to form distorted MgSn9 cuboctahedra that share corners with six equivalent SnMg6Sn6 cuboctahedra, corners with fifteen equivalent MgSn9 cuboctahedra, edges with three equivalent SnMg6Sn6 cuboctahedra, and faces with five equivalent MgSn9 cuboctahedra. There are six shorter (3.27 Å) and three longer (3.37 Å) Mg–Sn bond lengths. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 12-coordinate geometry to four equivalent Mg and two equivalent Sn atoms. Both Sn–Sn bond lengths are 3.30 Å. In the second Sn site, Sn is bonded to six equivalent Mg and six equivalent Sn atoms to form distorted SnMg6Sn6 cuboctahedra that share corners with twelve equivalent MgSn9 cuboctahedra, edges with six equivalent MgSn9 cuboctahedra, edges with six equivalent SnMg6Sn6 cuboctahedra, and faces with two equivalent SnMg6Sn6 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Recovered supernova Ia rate from simulated LSST images

Aims.TheVera C. RubinObservatory’s Legacy Survey of Space and Time (LSST) will revolutionize time-domain astronomy by detecting millions of different transients. In particular, it is expected to increase the number of known type Ia supernovae (SN Ia) by a factor of 100 compared to existing samples up to redshift ∼1.2. Such a high number of events will dramatically reduce statistical uncertainties in the analysis of the properties and rates of these objects. However, the impact of all other sources of uncertainty on the measurement of the SN Ia rate must still be evaluated. The comprehension and reduction of such uncertainties will be fundamental both for cosmology and stellar evolution studies, as measuring the SN Ia rate can put constraints on the evolutionary scenarios of different SN Ia progenitors. Methods.We used simulated data from the Dark Energy Science Collaboration (DESC) Data Challenge 2 (DC2) and LSST Data Preview 0 to measure the SN Ia rate on a 15 deg 2 region of the “wide-fast-deep” area. We selected a sample of SN candidates detected in difference images, associated them to the host galaxy with a specially developed algorithm, and retrieved their photometric redshifts. We then tested different light-curve classification methods, with and without redshift priors (albeit ignoring contamination from other transients, as DC2 contains only SN Ia). We discuss how the distribution in redshift measured for the SN candidates changes according to the selected host galaxy and redshift estimate. Results.We measured the SN Ia rate, analyzing the impact of uncertainties due to photometric redshift, host-galaxy association and classification on the distribution in redshift of the starting sample. We find that we are missing 17% of the SN Ia, on average, with respect to the simulated sample. As 10% of the mismatch is due to the uncertainty on the photometric redshift alone (which also affects classification when used as a prior), we conclude that this parameter is the major source of uncertainty. We discuss possible reduction of the errors in the measurement of the SN Ia rate, including synergies with other surveys, which may help us to use the rate to discriminate different progenitor models.

Astronomy & Astrophysics↗
DOE OSTI2026

Nb3Sn Superconducting Radiofrequency Cavity Fabricated by Sputter Deposition from a Stoichiometric Target

Nb$_3$Sn is a promising coating material for superconducting radiofrequency cavities in next-generation accelerators due to its higher superconducting transition temperature (~18.3 K) and superheating field (~400 mT), offering the potential to surpass the intrinsic performance limits of bulk niobium. We developed a sputter coating technique employing a stoichiometric target to fabricate Nb$_3$Sn films on the inner surfaces of niobium cavities. A Nb$_3$Sn tube target, prepared by growing a >20 m thick Nb$_3$Sn coating on the surface of a Nb tube via a Sn vapor diffusion process, was used in a DC cylindrical magnetron sputtering system. Approximately 170 nm thick Nb-Sn films were sputter-coated onto flat Nb substrates positioned to replicate the beam tube and equator regions of a 2.6 GHz cavity, followed by annealing at 950 °C for 3 hours to form Nb$_3$Sn. The composition, morphology, and structure of the annealed Nb$_3$Sn films were examined. Then, a ~1.2 m-thick film was sputter-coated onto the interior of a 2.6 GHz Nb cavity following the procedure developed for the flat samples. The cavity was subsequently annealed under the same conditions used for the flat samples. Cryogenic RF testing of the sputter-coated cavity demonstrated a T$_c$ of approximately 17.8 K, consistent with Nb$_3$Sn layer. Subsequently, the cavity underwent a light Sn recoating followed by a vapor diffusion Nb$_3$Sn coating process, achieving a quality factor of approximately 8.5 × 10$^9$ and an accelerating gradient of up to 11.3 MV/m at 4.2 K.

Shakel, Md Sharifuzzaman [Old Dominion U.; Jeffers↗
DOE OSTI2020

Materials Data on LaSnRh by Materials Project

LaRhSn crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. La is bonded in a 11-coordinate geometry to five Rh and six equivalent Sn atoms. There are four shorter (3.11 Å) and one longer (3.14 Å) La–Rh bond lengths. There are two shorter (3.33 Å) and four longer (3.47 Å) La–Sn bond lengths. There are two inequivalent Rh sites. In the first Rh site, Rh is bonded in a 9-coordinate geometry to three equivalent La and six equivalent Sn atoms. All Rh–Sn bond lengths are 2.83 Å. In the second Rh site, Rh is bonded in a 9-coordinate geometry to six equivalent La and three equivalent Sn atoms. All Rh–Sn bond lengths are 2.90 Å. Sn is bonded in a 12-coordinate geometry to six equivalent La, four Rh, and two equivalent Sn atoms. Both Sn–Sn bond lengths are 3.21 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sn3Pd by Materials Project

PdSn3 crystallizes in the orthorhombic Cmce space group. The structure is two-dimensional and consists of two PdSn3 sheets oriented in the (0, 1, 0) direction. Pd is bonded in a 9-coordinate geometry to eight Sn atoms. There are a spread of Pd–Sn bond distances ranging from 2.83–2.89 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 4-coordinate geometry to four equivalent Pd and one Sn atom. The Sn–Sn bond length is 3.00 Å. In the second Sn site, Sn is bonded in a 2-coordinate geometry to two equivalent Pd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sn2Pd by Materials Project

PdSn2 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional. Pd is bonded in a 8-coordinate geometry to one Pd and eight Sn atoms. The Pd–Pd bond length is 2.90 Å. There are a spread of Pd–Sn bond distances ranging from 2.85–2.88 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 7-coordinate geometry to four equivalent Pd and one Sn atom. The Sn–Sn bond length is 2.96 Å. In the second Sn site, Sn is bonded to four equivalent Pd atoms to form a mixture of distorted edge and corner-sharing SnPd4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na10YbSn12 by Materials Project

Na10YbSn12 crystallizes in the cubic I-43m space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded to four equivalent Sn atoms to form corner-sharing NaSn4 tetrahedra. All Na–Sn bond lengths are 3.24 Å. In the second Na site, Na is bonded in a 9-coordinate geometry to one Yb and nine equivalent Sn atoms. The Na–Yb bond length is 3.76 Å. There are three shorter (3.47 Å) and six longer (3.54 Å) Na–Sn bond lengths. Yb is bonded in a 12-coordinate geometry to four equivalent Na and twelve equivalent Sn atoms. All Yb–Sn bond lengths are 3.47 Å. Sn is bonded in a 9-coordinate geometry to five Na, one Yb, and three equivalent Sn atoms. There are one shorter (2.91 Å) and two longer (3.00 Å) Sn–Sn bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on UCoSn by Materials Project

UCoSn crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. U is bonded in a 11-coordinate geometry to five Co and six equivalent Sn atoms. There are four shorter (2.93 Å) and one longer (2.95 Å) U–Co bond lengths. There are two shorter (3.09 Å) and four longer (3.27 Å) U–Sn bond lengths. There are two inequivalent Co sites. In the first Co site, Co is bonded in a 9-coordinate geometry to six equivalent U and three equivalent Sn atoms. All Co–Sn bond lengths are 2.69 Å. In the second Co site, Co is bonded in a 9-coordinate geometry to three equivalent U and six equivalent Sn atoms. All Co–Sn bond lengths are 2.69 Å. Sn is bonded in a 12-coordinate geometry to six equivalent U, four Co, and two equivalent Sn atoms. Both Sn–Sn bond lengths are 3.06 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sn7Ir3 by Materials Project

Ir3Sn7 crystallizes in the cubic Im-3m space group. The structure is three-dimensional. Ir is bonded in a 8-coordinate geometry to eight Sn atoms. There are four shorter (2.79 Å) and four longer (2.81 Å) Ir–Sn bond lengths. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 4-coordinate geometry to three equivalent Ir and four equivalent Sn atoms. There are one shorter (2.81 Å) and three longer (3.14 Å) Sn–Sn bond lengths. In the second Sn site, Sn is bonded in a 8-coordinate geometry to four equivalent Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sn7Ru3 by Materials Project

Ru3Sn7 crystallizes in the cubic Im-3m space group. The structure is three-dimensional. Ru is bonded in a 8-coordinate geometry to eight Sn atoms. There are four shorter (2.78 Å) and four longer (2.79 Å) Ru–Sn bond lengths. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 8-coordinate geometry to four equivalent Ru atoms. In the second Sn site, Sn is bonded in a 3-coordinate geometry to three equivalent Ru and four equivalent Sn atoms. There are one shorter (2.92 Å) and three longer (3.05 Å) Sn–Sn bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sn7Os3 by Materials Project

Os3Sn7 crystallizes in the cubic Im-3m space group. The structure is three-dimensional. Os is bonded in a 8-coordinate geometry to eight Sn atoms. There are four shorter (2.78 Å) and four longer (2.80 Å) Os–Sn bond lengths. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded in a 8-coordinate geometry to four equivalent Os atoms. In the second Sn site, Sn is bonded in a 3-coordinate geometry to three equivalent Os and four equivalent Sn atoms. There are one shorter (2.93 Å) and three longer (3.06 Å) Sn–Sn bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na10CaSn12 by Materials Project

Na10CaSn12 crystallizes in the cubic I-43m space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded to four equivalent Sn atoms to form corner-sharing NaSn4 tetrahedra. All Na–Sn bond lengths are 3.24 Å. In the second Na site, Na is bonded in a 9-coordinate geometry to nine equivalent Sn atoms. There are three shorter (3.46 Å) and six longer (3.55 Å) Na–Sn bond lengths. Ca is bonded in a 12-coordinate geometry to twelve equivalent Sn atoms. All Ca–Sn bond lengths are 3.48 Å. Sn is bonded in a 9-coordinate geometry to five Na, one Ca, and three equivalent Sn atoms. There are one shorter (2.92 Å) and two longer (3.01 Å) Sn–Sn bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na10SrSn12 by Materials Project

Na10SrSn12 crystallizes in the cubic I-43m space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded to four equivalent Sn atoms to form corner-sharing NaSn4 tetrahedra. All Na–Sn bond lengths are 3.25 Å. In the second Na site, Na is bonded in a 9-coordinate geometry to nine equivalent Sn atoms. There are three shorter (3.45 Å) and six longer (3.58 Å) Na–Sn bond lengths. Sr is bonded in a 12-coordinate geometry to twelve equivalent Sn atoms. All Sr–Sn bond lengths are 3.51 Å. Sn is bonded in a 9-coordinate geometry to five Na, one Sr, and three equivalent Sn atoms. There are one shorter (2.95 Å) and two longer (3.03 Å) Sn–Sn bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SnAu5 by Materials Project

Au5Sn crystallizes in the trigonal R32 space group. The structure is three-dimensional. there are ten inequivalent Au+0.40- sites. In the first Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn2Au10 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.96–3.02 Å. All Au–Sn bond lengths are 3.00 Å. In the second Au+0.40- site, Au+0.40- is bonded to ten Au+0.40- and two equivalent Sn2+ atoms to form distorted AuSn2Au10 cuboctahedra that share corners with eighteen AuSn2Au10 cuboctahedra, edges with four equivalent SnAu12 cuboctahedra, edges with fourteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn3Au9 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.95–3.03 Å. Both Au–Sn bond lengths are 3.00 Å. In the third Au+0.40- site, Au+0.40- is bonded to ten Au+0.40- and two equivalent Sn2+ atoms to form distorted AuSn2Au10 cuboctahedra that share corners with eighteen AuSn2Au10 cuboctahedra, edges with four equivalent SnAu12 cuboctahedra, edges with fourteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn3Au9 cuboctahedra. There are one shorter (2.96 Å) and two longer (3.02 Å) Au–Au bond lengths. Both Au–Sn bond lengths are 3.00 Å. In the fourth Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn2Au10 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn2Au10 cuboctahedra. There are three shorter (3.01 Å) and two longer (3.02 Å) Au–Au bond lengths. All Au–Sn bond lengths are 3.00 Å. In the fifth Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn2Au10 cuboctahedra. Both Au–Au bond lengths are 2.96 Å. All Au–Sn bond lengths are 3.00 Å. In the sixth Au+0.40- site, Au+0.40- is bonded to ten Au+0.40- and two equivalent Sn2+ atoms to form distorted AuSn2Au10 cuboctahedra that share corners with eighteen AuSn2Au10 cuboctahedra, edges with four equivalent SnAu12 cuboctahedra, edges with fourteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn2Au10 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.95–3.03 Å. Both Au–Sn bond lengths are 3.00 Å. In the seventh Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn2Au10 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn3Au9 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.96–3.02 Å. All Au–Sn bond lengths are 3.00 Å. In the eighth Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn2Au10 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn2Au10 cuboctahedra. There are two shorter (2.96 Å) and one longer (3.02 Å) Au–Au bond lengths. All Au–Sn bond lengths are 3.00 Å. In the ninth Au+0.40- site, Au+0.40- is bonded to ten Au+0.40- and two equivalent Sn2+ atoms to form distorted AuSn2Au10 cuboctahedra that share corners with eighteen AuSn2Au10 cuboctahedra, edges with four equivalent SnAu12 cuboctahedra, edges with fourteen AuSn3Au9 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn3Au9 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.95–3.03 Å. Both Au–Sn bond lengths are 3.00 Å. In the tenth Au+0.40- site, Au+0.40- is bonded to nine Au+0.40- and three equivalent Sn2+ atoms to form distorted AuSn3Au9 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with eighteen AuSn2Au10 cuboctahedra, faces with four equivalent SnAu12 cuboctahedra, and faces with sixteen AuSn3Au9 cuboctahedra. The Au–Au bond length is 2.96 Å. All Au–Sn bond lengths are 3.00 Å. Sn2+ is bonded to twelve Au+0.40- atoms to form SnAu12 cuboctahedra that share corners with six equivalent SnAu12 cuboctahedra, corners with twelve AuSn3Au9 cuboctahedra, edges with six equivalent SnAu12 cuboctahedra, edges with twelve AuSn2Au10 cuboctahedra, and faces with twenty AuSn3Au9 cuboctahedra.

36 MATERIALS SCIENCE↗