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At least 973 records · Page 54
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Resolving local structural motifs across the phase evolution of zinc titanates with computational x-ray absorption spectroscopy

Resolving the local structure motifs that characterize phase evolution as a function of composition is a key challenge in structure characterization of complex materials. Here, in this study, we combine first-principles simulations and x-ray absorption near-edge structures (XANES) analysis to gain insights into the structure evolution revealed by measurements across a combinatorial zinc titanate thin film, which was grown with smoothly varying composition over a wide range of the Ti:Zn ratio. Specifically, we propose a cluster blind-signal-separation (cBSS) method for XANES spectral analysis based on a library of the structures and spectra of representative local motifs. In addition to motifs from zinc titanate crystals, two types of Ti-defect models constructed in this study are key to the understanding of the structure characteristics in the Zn-rich region. The cBSS method makes use of both spectral clustering of the simulated site-XANES spectra library and the BSS procedure to construct high-fidelity spectral basis functions from an experimental spectral sequence. The method provides a rigorous measure of the spectral sensitivity and basis completeness. The results of the XANES analysis are corroborated with other experimental modalities, including x-ray diffraction and spectroscopic ellipsometry, to validate the cBSS method. The calculated motif weights resulting from fitting the XANES spectra with the cBSS basis probe the atomic structure characteristics of both crystalline and amorphous phases as a function of the Ti/Zn composition. The insights of the local structure motif evolution are pivotal to the understanding of the nonmonotonic trend in the optical gap, which may lead to potential applications through tuning the optical properties of zinc titanate. The workflow of the XANES spectral analysis developed in this work can be generalized to construct the structure-property relationship in a broad material space.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZrI2 by Materials Project

ZrI2 is Tungsten structured and crystallizes in the trigonal R-3 space group. The structure is zero-dimensional and consists of three ZrI2 clusters. Zr2+ is bonded in a distorted square co-planar geometry to four I1- atoms. There are a spread of Zr–I bond distances ranging from 2.89–2.97 Å. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a 2-coordinate geometry to two equivalent Zr2+ atoms. In the second I1- site, I1- is bonded in a 2-coordinate geometry to two equivalent Zr2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MnMo3 by Materials Project

Mo3Mn crystallizes in the monoclinic C2 space group. The structure is zero-dimensional and consists of two Mo3Mn clusters. there are two inequivalent Mo sites. In the first Mo site, Mo is bonded in a single-bond geometry to one Mn atom. The Mo–Mn bond length is 2.34 Å. In the second Mo site, Mo is bonded in a single-bond geometry to one Mn atom. The Mo–Mn bond length is 2.34 Å. Mn is bonded in a distorted trigonal planar geometry to three Mo atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sb2XeF15 by Materials Project

XeF4Sb2F11 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of four Sb2F11 clusters and four XeF4 clusters. In each Sb2F11 cluster, Sb is bonded to six F atoms to form corner-sharing SbF6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Sb–F bond distances ranging from 1.89–2.08 Å. There are six inequivalent F sites. In the first F site, F is bonded in a linear geometry to two equivalent Sb atoms. In the second F site, F is bonded in a single-bond geometry to one Sb atom. In the third F site, F is bonded in a single-bond geometry to one Sb atom. In the fourth F site, F is bonded in a single-bond geometry to one Sb atom. In the fifth F site, F is bonded in a single-bond geometry to one Sb atom. In the sixth F site, F is bonded in a single-bond geometry to one Sb atom. In each XeF4 cluster, Xe is bonded in a square co-planar geometry to four F atoms. There are two shorter (2.00 Å) and two longer (2.02 Å) Xe–F bond lengths. There are two inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Xe atom. In the second F site, F is bonded in a single-bond geometry to one Xe atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SbCl5 by Materials Project

SbCl5 is beta Sn-like structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is zero-dimensional and consists of two SbCl5 clusters. Sb5+ is bonded in a trigonal bipyramidal geometry to five Cl1- atoms. There are three shorter (2.33 Å) and two longer (2.38 Å) Sb–Cl bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Sb5+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Sb5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SbSCl9 by Materials Project

SbCl6SCl3 is Molybdenum Carbide MAX Phase-like structured and crystallizes in the monoclinic C2/m space group. The structure is zero-dimensional and consists of four SCl3 clusters and four SbCl6 clusters. In each SCl3 cluster, S6+ is bonded in a trigonal non-coplanar geometry to three Cl1- atoms. There are two shorter (2.00 Å) and one longer (2.01 Å) S–Cl bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one S6+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one S6+ atom. In two of the SbCl6 clusters, Sb3+ is bonded in an octahedral geometry to six Cl1- atoms. There are two shorter (2.38 Å) and four longer (2.43 Å) Sb–Cl bond lengths. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Sb3+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Sb3+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Sb3+ atom. In two of the SbCl6 clusters, Sb3+ is bonded in an octahedral geometry to six Cl1- atoms. There are two shorter (2.41 Å) and four longer (2.42 Å) Sb–Cl bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Sb3+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Sb3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ga(BiCl)4 by Materials Project

(Bi)4GaCl4 crystallizes in the hexagonal P6_3 space group. The structure is zero-dimensional and consists of six Bi clusters and twelve GaCl4 clusters. In each Bi cluster, there are eight inequivalent Bi sites. In the first Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. There are a spread of Bi–Bi bond distances ranging from 3.09–3.19 Å. In the second Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. There are one shorter (3.10 Å) and two longer (3.18 Å) Bi–Bi bond lengths. In the third Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. There are a spread of Bi–Bi bond distances ranging from 3.10–3.18 Å. In the fourth Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. There are a spread of Bi–Bi bond distances ranging from 3.09–3.18 Å. In the fifth Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. The Bi–Bi bond length is 3.09 Å. In the sixth Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. There are one shorter (3.09 Å) and one longer (3.17 Å) Bi–Bi bond lengths. In the seventh Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. In the eighth Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. In each GaCl4 cluster, Ga is bonded in a tetrahedral geometry to four Cl atoms. There are one shorter (2.20 Å) and three longer (2.22 Å) Ga–Cl bond lengths. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a single-bond geometry to one Ga atom. In the second Cl site, Cl is bonded in a single-bond geometry to one Ga atom.

36 MATERIALS SCIENCE↗
DOE OSTI2021

The large-scale environment of thermonuclear and core-collapse supernovae

ABSTRACT The new generation of wide-field time-domain surveys has made it feasible to study the clustering of supernova (SN) host galaxies in the large-scale structure (LSS) for the first time. We investigate the LSS environment of SN populations, using 106 dark matter density realisations with a resolution of ∼3.8 Mpc, constrained by the 2M+ + galaxy survey. We limit our analysis to redshift z < 0.036, using samples of 498 thermonuclear and 782 core-collapse SNe from the Zwicky Transient Facility’s Bright Transient Survey and Census of the Local Universe catalogues. We detect clustering of SNe with high significance; the observed clustering of the two SNe populations is consistent with each other. Further, the clustering of SN hosts is consistent with that of the Sloan Digital Sky Survey (SDSS) Baryon Oscillation Spectroscopic Survey DR12 spectroscopic galaxy sample in the same redshift range. Using a tidal shear classifier, we classify the LSS into voids, sheets, filaments, and knots. We find that both SNe and SDSS galaxies are predominantly found in sheets and filaments. SNe are significantly under-represented in voids and over-represented in knots compared to the volume fraction in these structures. This work opens the potential for using forthcoming wide-field deep SN surveys as a complementary LSS probe.

Astronomy & Astrophysics↗
DOE OSTI2020

Materials Data on SbS2NCl6 by Materials Project

NS2SbCl6 is Halite, Rock Salt-like structured and crystallizes in the orthorhombic Immm space group. The structure is zero-dimensional and consists of two NS2 clusters and two SbCl6 clusters. In each NS2 cluster, N5+ is bonded in a linear geometry to two equivalent S2- atoms. Both N–S bond lengths are 1.50 Å. S2- is bonded in a single-bond geometry to one N5+ atom. In each SbCl6 cluster, Sb5+ is bonded in an octahedral geometry to six Cl1- atoms. There are two shorter (2.40 Å) and four longer (2.42 Å) Sb–Cl bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Sb5+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Sb5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re2SCl12 by Materials Project

Re2Cl9SCl3 crystallizes in the monoclinic P2_1/m space group. The structure is zero-dimensional and consists of two Re2Cl9 clusters and two SCl3 clusters. In each Re2Cl9 cluster, there are two inequivalent Re7+ sites. In the first Re7+ site, Re7+ is bonded to six Cl1- atoms to form face-sharing ReCl6 octahedra. There are three shorter (2.34 Å) and three longer (2.41 Å) Re–Cl bond lengths. In the second Re7+ site, Re7+ is bonded to six Cl1- atoms to form face-sharing ReCl6 octahedra. There are three shorter (2.30 Å) and three longer (2.45 Å) Re–Cl bond lengths. There are six inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Re7+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Re7+ atom. In the third Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Re7+ atom. In the fourth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Re7+ atoms. In the fifth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Re7+ atom. In the sixth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Re7+ atoms. In each SCl3 cluster, S2- is bonded in a 3-coordinate geometry to three Cl1- atoms. There are one shorter (2.02 Å) and two longer (2.03 Å) S–Cl bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one S2- atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one S2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H3NCl by Materials Project

NH3Cl is Copper structured and crystallizes in the cubic Pa-3 space group. The structure is zero-dimensional and consists of four NH3Cl clusters. N2- is bonded in a trigonal non-coplanar geometry to three equivalent H1+ and one Cl1- atom. All N–H bond lengths are 1.02 Å. The N–Cl bond length is 2.46 Å. H1+ is bonded in a single-bond geometry to one N2- atom. Cl1- is bonded in a linear geometry to one N2- and one Cl1- atom. The Cl–Cl bond length is 2.24 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AsF5 by Materials Project

AsF5 crystallizes in the hexagonal P6_3/mmc space group. The structure is zero-dimensional and consists of two AsF5 clusters. As5+ is bonded in a trigonal bipyramidal geometry to five F1- atoms. There is three shorter (1.72 Å) and two longer (1.75 Å) As–F bond length. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BrNO by Materials Project

ONBr crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two ONBr clusters. N3- is bonded in a single-bond geometry to one O2- and two equivalent Br5+ atoms. The N–O bond length is 1.14 Å. There are one shorter (2.47 Å) and one longer (2.54 Å) N–Br bond lengths. O2- is bonded in a single-bond geometry to one N3- atom. Br5+ is bonded in a distorted L-shaped geometry to two equivalent N3- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BSF7 by Materials Project

BF4SF3 is Modderite structured and crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four BF4 clusters and four SF3 clusters. In each BF4 cluster, B3+ is bonded in a tetrahedral geometry to four F1- atoms. There are a spread of B–F bond distances ranging from 1.40–1.43 Å. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one B3+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one B3+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one B3+ atom. In each SF3 cluster, S4+ is bonded in a 3-coordinate geometry to three F1- atoms. There is one shorter (1.55 Å) and two longer (1.56 Å) S–F bond length. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one S4+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one S4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SbSCl9 by Materials Project

SbCl6SCl3 crystallizes in the monoclinic C2/m space group. The structure is zero-dimensional and consists of four SCl3 clusters and four SbCl6 clusters. In each SCl3 cluster, S6+ is bonded in a trigonal non-coplanar geometry to three equivalent Cl1- atoms. All S–Cl bond lengths are 2.00 Å. Cl1- is bonded in a single-bond geometry to one S6+ atom. In two of the SbCl6 clusters, Sb3+ is bonded in an octahedral geometry to six equivalent Cl1- atoms. All Sb–Cl bond lengths are 2.42 Å. Cl1- is bonded in a single-bond geometry to one Sb3+ atom. In two of the SbCl6 clusters, Sb3+ is bonded in an octahedral geometry to six equivalent Cl1- atoms. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Sb3+ atom. The Cl–Sb bond length is 2.41 Å. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Sb3+ atom. The Cl–Sb bond length is 2.41 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ClF3 by Materials Project

ClF3 is High Pressure (4-7GPa) Tellurium structured and crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four ClF3 clusters. Cl is bonded in a T-shaped geometry to three F atoms. There is one shorter (1.64 Å) and two longer (1.75 Å) Cl–F bond length. There are two inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Cl atom. In the second F site, F is bonded in a single-bond geometry to one Cl atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on C3N2 by Materials Project

C3N2 is alpha Po structured and crystallizes in the cubic P-43m space group. The structure is zero-dimensional and consists of one C3N2 cluster. C2+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.43 Å) and one longer (1.44 Å) C–N bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a trigonal planar geometry to three equivalent C2+ atoms. In the second N3- site, N3- is bonded in a trigonal planar geometry to three equivalent C2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg3(ClO5)2 by Materials Project

Hg3O2(ClO4)2 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of eight ClO4 clusters and four Hg3O2 clusters. In each ClO4 cluster, there are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. In the second O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. In the third O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. In the fourth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.47 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In each Hg3O2 cluster, there are two inequivalent Hg sites. In the first Hg site, Hg is bonded in a single-bond geometry to one O atom. The Hg–O bond length is 2.13 Å. In the second Hg site, Hg is bonded in a linear geometry to two equivalent O atoms. Both Hg–O bond lengths are 1.97 Å. O is bonded in a bent 120 degrees geometry to two Hg atoms.

36 MATERIALS SCIENCE↗