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At least 1,117 records · Page 62
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Structure and dynamics of $\mathrm{Fe_{90}}$$\mathrm{Si_3}$$\mathrm{O_7}$ liquids close to Earth's liquid core conditions

Using an artificial neural-network machine learning interatomic potential, we have performed molecular dynamics simulations to study the structure and dynamics of $\mathrm{Fe_{90}}$$\mathrm{Si_3}$$\mathrm{O_7}$ liquid close to the Earth's liquid core conditions. Here, the simulation results reveal that the short-range structural order (SRO) in the $\mathrm{Fe_{90}}$$\mathrm{Si_3}$$\mathrm{O_7}$ liquid is very strong. About 80% of the atoms are arranged in crystallinelike SRO motifs. In particular, ~ $70$% of Fe-centered clusters can be classified as either hexagonal-close-packed-like or icosahedrallike SRO motifs. The SRO clusters centered on Fe, Si, or O atoms are strongly intermixed and homogenously distributed throughout the liquid. The atomic structure of the liquid and the fractions of dominant SRO clusters are not sensitive to pressure/temperature used in the simulations except that the SRO of the O-centered clusters is enhanced close to inner core pressures. The O-diffusion coefficient is about two to three times larger than the Fe and Si ions and increases more rapidly in the deeper core regions.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2020

Materials Data on AuNCl3 by Materials Project

AuNCl3 is High Pressure (4-7GPa) Tellurium structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four AuNCl3 clusters. Au5+ is bonded in a rectangular see-saw-like geometry to one N2- and three Cl1- atoms. The Au–N bond length is 1.93 Å. There are two shorter (2.31 Å) and one longer (2.35 Å) Au–Cl bond lengths. N2- is bonded in a single-bond geometry to one Au5+ atom. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Au5+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Au5+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Au5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AlHg2O2F5 by Materials Project

(HgO)2AlF5 crystallizes in the tetragonal I4cm space group. The structure is two-dimensional and consists of four AlF5 clusters and two HgO sheets oriented in the (0, 0, 1) direction. In each AlF5 cluster, Al is bonded in a square pyramidal geometry to five F atoms. There is four shorter (1.78 Å) and one longer (1.80 Å) Al–F bond length. There are two inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Al atom. In the second F site, F is bonded in a single-bond geometry to one Al atom. In each HgO sheet, Hg is bonded in a 5-coordinate geometry to three equivalent O atoms. There are one shorter (2.21 Å) and two longer (2.36 Å) Hg–O bond lengths. O is bonded in a trigonal planar geometry to three equivalent Hg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2022

A pair of early- and late-forming galaxy cluster samples: A novel way of studying halo assembly bias assisted by a constrained simulation

The halo assembly bias, a phenomenon referring to dependencies of the large-scale bias of a dark matter halo other than its mass, is a fundamental property of the standard cosmological model. First discovered in 2005 from the Millennium Run simulation, it has been proven very difficult to be detected observationally, with only a few convincing claims of detection so far. The main obstacle lies in finding an accurate proxy of the halo formation time. In this study, by utilizing a constrained simulation that can faithfully reproduce the observed structures larger than 2 Mpc in the local universe, for a sample of 634 massive clusters at z ≤ 0.12, we found their counterpart halos in the simulation and used the mass growth history of the matched halos to estimate the formation time of the observed clusters. This allowed us to construct a pair of early- and late-forming clusters, with a similar mass as measured via weak gravitational lensing, and large-scale biases differing at the ≈3σ level, suggestive of the signature of assembly bias, which is further corroborated by the properties of cluster galaxies, including the brightest cluster galaxy and the spatial distribution and number of member galaxies. Our study paves a way to further detect assembly bias based on cluster samples constructed purely on observed quantities.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2020

Materials Data on SnAsF7 by Materials Project

Sn3As2F15AsF6 is Molybdenum Carbide MAX Phase-like structured and crystallizes in the trigonal R32 space group. The structure is zero-dimensional and consists of three AsF6 clusters and three Sn3As2F15 clusters. In each AsF6 cluster, As5+ is bonded in an octahedral geometry to six equivalent F1- atoms. All As–F bond lengths are 1.78 Å. F1- is bonded in a single-bond geometry to one As5+ atom. In each Sn3As2F15 cluster, Sn2+ is bonded in a 2-coordinate geometry to four F1- atoms. There are two shorter (2.14 Å) and two longer (2.59 Å) Sn–F bond lengths. As5+ is bonded in an octahedral geometry to six F1- atoms. There is three shorter (1.76 Å) and three longer (1.79 Å) As–F bond length. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a bent 150 degrees geometry to two equivalent Sn2+ atoms. In the second F1- site, F1- is bonded in a distorted single-bond geometry to one Sn2+ and one As5+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one As5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SbOF3 by Materials Project

SbOF3 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two SbOF3 clusters. Sb5+ is bonded to two equivalent O2- and three F1- atoms to form edge-sharing SbO2F3 trigonal bipyramids. There is one shorter (1.96 Å) and one longer (2.02 Å) Sb–O bond length. There are a spread of Sb–F bond distances ranging from 1.88–1.90 Å. O2- is bonded in a water-like geometry to two equivalent Sb5+ atoms. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Sb5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Sb5+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one Sb5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on IF5 by Materials Project

IF5 is beta-like structured and crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of twenty IF5 clusters. I5+ is bonded in a square pyramidal geometry to five F1- atoms. There is one shorter (1.85 Å) and four longer (1.93 Å) I–F bond length. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one I5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one I5+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one I5+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one I5+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one I5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sb2XeF16 by Materials Project

XeF5Sb2F11 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two Sb2F11 clusters and two XeF5 clusters. In each Sb2F11 cluster, there are two inequivalent Sb sites. In the first Sb site, Sb is bonded to six F atoms to form corner-sharing SbF6 octahedra. The corner-sharing octahedral tilt angles are 35°. There are a spread of Sb–F bond distances ranging from 1.89–2.08 Å. In the second Sb site, Sb is bonded to six F atoms to form corner-sharing SbF6 octahedra. The corner-sharing octahedral tilt angles are 35°. There are a spread of Sb–F bond distances ranging from 1.89–2.08 Å. There are eleven inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Sb atom. 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 the seventh F site, F is bonded in a single-bond geometry to one Sb atom. In the eighth F site, F is bonded in a single-bond geometry to one Sb atom. In the ninth F site, F is bonded in a bent 150 degrees geometry to two Sb atoms. In the tenth F site, F is bonded in a single-bond geometry to one Sb atom. In the eleventh F site, F is bonded in a single-bond geometry to one Sb atom. In each XeF5 cluster, Xe is bonded in a square pyramidal geometry to five F atoms. There is four shorter (1.96 Å) and one longer (1.97 Å) Xe–F bond length. There are five 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. In the third F site, F is bonded in a single-bond geometry to one Xe atom. In the fourth F site, F is bonded in a single-bond geometry to one Xe atom. In the fifth F site, F is bonded in a single-bond geometry to one Xe atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AgH3BrN by Materials Project

AgNH3Br crystallizes in the monoclinic P2_1/m space group. The structure is zero-dimensional and consists of two AgNH3Br clusters. Ag1+ is bonded in a 2-coordinate geometry to one N3- and one Br1- atom. The Ag–N bond length is 2.20 Å. The Ag–Br bond length is 2.53 Å. N3- is bonded in a distorted trigonal non-coplanar geometry to one Ag1+ and three H1+ atoms. There is one shorter (1.02 Å) and two longer (1.03 Å) N–H bond length. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. Br1- is bonded in a 1-coordinate geometry to one Ag1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SbClF10 by Materials Project

SbF6ClF4 crystallizes in the orthorhombic Pbcm space group. The structure is zero-dimensional and consists of four ClF4 clusters and four SbF6 clusters. In each ClF4 cluster, Cl is bonded in a rectangular see-saw-like geometry to four F atoms. There are a spread of Cl–F bond distances ranging from 1.59–1.67 Å. 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. In each SbF6 cluster, Sb is bonded in an octahedral geometry to six F atoms. There are a spread of Sb–F bond distances ranging from 1.90–1.97 Å. There are five inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Sb atom. 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.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PtCI2O by Materials Project

PtCOI2 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of four PtCOI2 clusters. Pt2+ is bonded in a rectangular see-saw-like geometry to one C2+ and three I1- atoms. The Pt–C bond length is 1.86 Å. There are a spread of Pt–I bond distances ranging from 2.64–2.67 Å. C2+ is bonded in a distorted linear geometry to one Pt2+ and one O2- atom. The C–O bond length is 1.15 Å. O2- is bonded in a single-bond geometry to one C2+ atom. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a distorted single-bond geometry to one Pt2+ atom. In the second I1- site, I1- is bonded in an L-shaped geometry to two equivalent Pt2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HgBrO3 by Materials Project

HgO3Br crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of eight HgO3Br clusters. Hg1+ is bonded in a 1-coordinate geometry to one O2- atom. The Hg–O bond length is 2.21 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Br5+ atom. The O–Br bond length is 1.68 Å. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Br5+ atom. The O–Br bond length is 1.67 Å. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Hg1+ and one Br5+ atom. The O–Br bond length is 1.75 Å. Br5+ is bonded in a trigonal non-coplanar geometry to three O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AsCl3O by Materials Project

AsOCl3 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two AsOCl3 clusters. As5+ is bonded to two equivalent O2- and three Cl1- atoms to form edge-sharing AsCl3O2 trigonal bipyramids. There is one shorter (1.77 Å) and one longer (1.93 Å) As–O bond length. There are a spread of As–Cl bond distances ranging from 2.16–2.22 Å. O2- is bonded in a water-like geometry to two equivalent As5+ atoms. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one As5+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one As5+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one As5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HgClO3 by Materials Project

HgO3Cl crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight HgO3Cl clusters. Hg is bonded in a distorted single-bond geometry to one O atom. The Hg–O bond length is 2.25 Å. There are three 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 1.49 Å. In the second O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.48 Å. In the third O site, O is bonded in a water-like geometry to one Hg and one Cl atom. The O–Cl bond length is 1.59 Å. Cl is bonded in a trigonal non-coplanar geometry to three O atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sb4Au(Xe2F11)2 by Materials Project

Xe4Au(Sb2F11)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of four Sb2F11 clusters and two Xe4Au clusters. In two of the Sb2F11 clusters, there are two inequivalent Sb sites. In the first Sb site, Sb is bonded to six F atoms to form corner-sharing SbF6 octahedra. The corner-sharing octahedral tilt angles are 31°. There are a spread of Sb–F bond distances ranging from 1.90–2.10 Å. In the second Sb site, Sb is bonded to six F atoms to form corner-sharing SbF6 octahedra. The corner-sharing octahedral tilt angles are 31°. There are a spread of Sb–F bond distances ranging from 1.89–2.07 Å. There are eleven inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Sb atom. 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 bent 150 degrees geometry to two Sb atoms. 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 the seventh F site, F is bonded in a single-bond geometry to one Sb atom. In the eighth F site, F is bonded in a single-bond geometry to one Sb atom. In the ninth F site, F is bonded in a single-bond geometry to one Sb atom. In the tenth F site, F is bonded in a single-bond geometry to one Sb atom. In the eleventh F site, F is bonded in a single-bond geometry to one Sb atom. In two of the Sb2F11 clusters, there are two inequivalent Sb sites. In the first Sb site, Sb is bonded to six F atoms to form corner-sharing SbF6 octahedra. The corner-sharing octahedral tilt angles are 26°. There are a spread of Sb–F bond distances ranging from 1.89–2.12 Å. In the second Sb site, Sb is bonded to six F atoms to form corner-sharing SbF6 octahedra. The corner-sharing octahedral tilt angles are 26°. There are a spread of Sb–F bond distances ranging from 1.89–2.05 Å. There are eleven inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Sb atom. 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 the seventh F site, F is bonded in a single-bond geometry to one Sb atom. In the eighth F site, F is bonded in a single-bond geometry to one Sb atom. In the ninth F site, F is bonded in a single-bond geometry to one Sb atom. In the tenth F site, F is bonded in a single-bond geometry to one Sb atom. In the eleventh F site, F is bonded in a bent 150 degrees geometry to two Sb atoms. In each Xe4Au cluster, there are four inequivalent Xe sites. In the first Xe site, Xe is bonded in a single-bond geometry to one Au atom. The Xe–Au bond length is 2.81 Å. In the second Xe site, Xe is bonded in a single-bond geometry to one Au atom. The Xe–Au bond length is 2.81 Å. In the third Xe site, Xe is bonded in a single-bond geometry to one Au atom. The Xe–Au bond length is 2.82 Å. In the fourth Xe site, Xe is bonded in a single-bond geometry to one Au atom. The Xe–Au bond length is 2.82 Å. Au is bonded in a 5-coordinate geometry to four Xe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H6AuN2ClO4 by Materials Project

AuN2H6ClO4 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of four AuN2H6 clusters and four ClO4 clusters. In two of the AuN2H6 clusters, Au1+ is bonded in a linear geometry to two equivalent N1+ atoms. Both Au–N bond lengths are 2.08 Å. N1+ is bonded in a trigonal non-coplanar geometry to one Au1+ and three H1+ atoms. All N–H bond lengths are 1.03 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N1+ atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N1+ atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N1+ atom. In two of the AuN2H6 clusters, Au1+ is bonded in a linear geometry to two N1+ atoms. Both Au–N bond lengths are 2.08 Å. There are two inequivalent N1+ sites. In the first N1+ site, N1+ is bonded in a trigonal non-coplanar geometry to one Au1+ and three H1+ atoms. There is one shorter (1.02 Å) and two longer (1.03 Å) N–H bond length. In the second N1+ site, N1+ is bonded in a trigonal non-coplanar geometry to one Au1+ and three H1+ atoms. There is two shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N1+ atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N1+ atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N1+ atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N1+ atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N1+ atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N1+ atom. In each ClO4 cluster, there are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.46 Å. In the second O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.46 Å. In the third O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.46 Å. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.47 Å. Cl1- is bonded in a tetrahedral geometry to four O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CuPb2Cl3O2 by Materials Project

CuCl3(PbO)2 crystallizes in the tetragonal I4_1/acd space group. The structure is one-dimensional and consists of eight PbO clusters and four CuCl3 ribbons oriented in the (0, 0, 1) direction. In each PbO cluster, Pb3+ is bonded in a 3-coordinate geometry to three equivalent O2- atoms. There are one shorter (2.28 Å) and two longer (2.29 Å) Pb–O bond lengths. O2- is bonded in a distorted trigonal non-coplanar geometry to three equivalent Pb3+ atoms. In each CuCl3 ribbon, Cu1+ is bonded to four Cl1- atoms to form corner-sharing CuCl4 tetrahedra. There are two shorter (2.28 Å) and two longer (2.43 Å) Cu–Cl bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Cu1+ atom. In the second Cl1- site, Cl1- is bonded in a distorted bent 120 degrees geometry to two equivalent Cu1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PaBr5 by Materials Project

PaBr5 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two PaBr5 clusters. Pa5+ is bonded to six Br1- atoms to form edge-sharing PaBr6 octahedra. There are a spread of Pa–Br bond distances ranging from 2.65–2.91 Å. There are five inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a single-bond geometry to one Pa5+ atom. In the second Br1- site, Br1- is bonded in a water-like geometry to two equivalent Pa5+ atoms. In the third Br1- site, Br1- is bonded in a single-bond geometry to one Pa5+ atom. In the fourth Br1- site, Br1- is bonded in a single-bond geometry to one Pa5+ atom. In the fifth Br1- site, Br1- is bonded in a single-bond geometry to one Pa5+ atom.

36 MATERIALS SCIENCE↗