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At least 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on ZrP2NCl11 by Materials Project

ZrCl5P2NCl6 crystallizes in the orthorhombic Cmce space group. The structure is zero-dimensional and consists of eight P2NCl6 clusters and four ZrCl5 clusters. In each P2NCl6 cluster, P5+ is bonded to one N3- and three Cl1- atoms to form corner-sharing PNCl3 tetrahedra. The P–N bond length is 1.57 Å. There is one shorter (1.97 Å) and two longer (1.98 Å) P–Cl bond length. N3- is bonded in a bent 150 degrees geometry to two equivalent P5+ atoms. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In each ZrCl5 cluster, Zr4+ is bonded to six Cl1- atoms to form edge-sharing ZrCl6 octahedra. There are a spread of Zr–Cl bond distances ranging from 2.41–2.68 Å. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a water-like geometry to two equivalent Zr4+ atoms. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Zr4+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Zr4+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one Zr4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Al12Ge(Se2O35)2 by Materials Project

Al12GeO36(SeO4)2(SeO3)2(O2)10 crystallizes in the monoclinic C2 space group. The structure is zero-dimensional and consists of eight oxygen molecules, six trioxidane molecules, six water molecules, two Al12GeO36 clusters, four SeO3 clusters, and four SeO4 clusters. In each Al12GeO36 cluster, there are six inequivalent Al sites. In the first Al site, Al is bonded in a distorted square co-planar geometry to four O atoms. There are a spread of Al–O bond distances ranging from 1.77–1.85 Å. In the second Al site, Al is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Al–O bond distances ranging from 1.81–2.41 Å. In the third Al site, Al is bonded to five O atoms to form distorted AlO5 trigonal bipyramids that share a cornercorner with one AlO5 trigonal bipyramid and an edgeedge with one AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.83–1.89 Å. In the fourth Al site, Al is bonded to five O atoms to form distorted AlO5 trigonal bipyramids that share a cornercorner with one GeO4 tetrahedra, a cornercorner with one AlO5 trigonal bipyramid, and an edgeedge with one AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.79–1.97 Å. In the fifth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share a cornercorner with one GeO4 tetrahedra, an edgeedge with one AlO6 octahedra, and an edgeedge with one AlO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.82–2.06 Å. In the sixth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share a cornercorner with one GeO4 tetrahedra, an edgeedge with one AlO6 octahedra, and an edgeedge with one AlO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.83–2.00 Å. Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with four AlO6 octahedra and corners with two equivalent AlO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 52°. There is two shorter (1.75 Å) and two longer (1.81 Å) Ge–O bond length. There are eighteen inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to two Al atoms. In the second O site, O is bonded in a water-like geometry to two Al atoms. In the third O site, O is bonded in a single-bond geometry to one Al atom. In the fourth O site, O is bonded in a water-like geometry to two Al atoms. In the fifth O site, O is bonded in a water-like geometry to two Al atoms. In the sixth O site, O is bonded in a water-like geometry to two Al atoms. In the seventh O site, O is bonded in a water-like geometry to two Al atoms. In the eighth O site, O is bonded in a trigonal planar geometry to two Al and one Ge atom. In the ninth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Al and one Ge atom. In the tenth O site, O is bonded in a single-bond geometry to one Al atom. In the eleventh O site, O is bonded in a single-bond geometry to one Al atom. In the twelfth O site, O is bonded in a single-bond geometry to one Al atom. In the thirteenth O site, O is bonded in a single-bond geometry to one Al atom. In the fourteenth O site, O is bonded in an L-shaped geometry to two equivalent Al atoms. In the fifteenth O site, O is bonded in a water-like geometry to two equivalent Al atoms. In the sixteenth O site, O is bonded in a water-like geometry to two Al atoms. In the seventeenth O site, O is bonded in a water-like geometry to two Al atoms. In the eighteenth O site, O is bonded in a bent 120 degrees geometry to two Al atoms. In each SeO3 cluster, Se is bonded in a trigonal planar geometry to three O atoms. All Se–O bond lengths are 1.63 Å. There are three inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Se atom. In the second O site, O is bonded in a single-bond geometry to one Se atom. In the third O site, O is bonded in a single-bond geometry to one Se atom. In each SeO4 cluster, Se is bonded in a tetrahedral geometry to four O atoms. There are a spread of Se–O bond distances ranging from 1.65–1.75 Å. There are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Se atom. In the second O site, O is bonded in a single-bond geometry to one Se atom. In the third O site, O is bonded in a single-bond geometry to one Se atom. In the fourth O site, O is bonded in a single-bond geometry to one Se atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TeC4S4N8(ClO4)2 by Materials Project

C2Te(N2S)2(CN2SO)2(ClO3)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two C2Te(N2S)2 clusters, four CN2SO clusters, and four ClO3 clusters. In each C2Te(N2S)2 cluster, there are two inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a linear geometry to two N+0.75+ atoms. There is one shorter (1.18 Å) and one longer (1.31 Å) C–N bond length. In the second C4+ site, C4+ is bonded in a linear geometry to two N+0.75+ atoms. There is one shorter (1.18 Å) and one longer (1.29 Å) C–N bond length. There are four inequivalent N+0.75+ sites. In the first N+0.75+ site, N+0.75+ is bonded in a single-bond geometry to one C4+ atom. In the second N+0.75+ site, N+0.75+ is bonded in a distorted bent 120 degrees geometry to one C4+ and one S2- atom. The N–S bond length is 1.58 Å. In the third N+0.75+ site, N+0.75+ is bonded in a single-bond geometry to one C4+ atom. In the fourth N+0.75+ site, N+0.75+ is bonded in a distorted bent 120 degrees geometry to one C4+ and one S2- atom. The N–S bond length is 1.57 Å. Te4+ is bonded in a distorted bent 150 degrees geometry to two S2- atoms. There are one shorter (2.44 Å) and one longer (2.55 Å) Te–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted water-like geometry to one N+0.75+ and one Te4+ atom. In the second S2- site, S2- is bonded in a distorted bent 120 degrees geometry to one N+0.75+ and one Te4+ atom. In each CN2SO cluster, C4+ is bonded in a linear geometry to two N+0.75+ atoms. There is one shorter (1.18 Å) and one longer (1.31 Å) C–N bond length. There are two inequivalent N+0.75+ sites. In the first N+0.75+ site, N+0.75+ is bonded in a single-bond geometry to one C4+ atom. In the second N+0.75+ site, N+0.75+ is bonded in a distorted bent 120 degrees geometry to one C4+ and one S2- atom. The N–S bond length is 1.56 Å. S2- is bonded in a distorted bent 120 degrees geometry to one N+0.75+ and one O2- atom. The S–O bond length is 1.45 Å. O2- is bonded in a single-bond geometry to one S2- atom. In each ClO3 cluster, there are three 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 1.47 Å. In the second O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.49 Å. In the third O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.48 Å. Cl1- is bonded in a trigonal non-coplanar geometry to three O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Regioselective Generation of Single‐Site Iridium Atoms and Their Evolution into Stabilized Subnanometric Iridium Clusters in MWW Zeolite

Abstract Preparation of supported metal catalysts with uniform particle size and coordination environment is a challenging and important topic in materials chemistry and catalysis. In this work, we report the regioselective generation of single‐site Ir atoms and their evolution into stabilized subnanometric Ir clusters in MWW zeolite, which are located at the 10MR window connecting the two neighboring 12MR supercages. The size of the subnanometric Ir clusters can be controlled by the post‐synthesis treatments and maintain below 1 nm even after being reduced at 650 °C, which cannot be readily achieved with samples prepared by conventional impregnation methods. The high structure sensitivity, size‐dependence, of catalytic performance in the alkane hydrogenolysis reaction of Ir clusters in the subnanometric regime is evidenced.

Liu, Lichen↗
DOE OSTI2020

Regioselective Generation of Single‐Site Iridium Atoms and Their Evolution into Stabilized Subnanometric Iridium Clusters in MWW Zeolite

Abstract Preparation of supported metal catalysts with uniform particle size and coordination environment is a challenging and important topic in materials chemistry and catalysis. In this work, we report the regioselective generation of single‐site Ir atoms and their evolution into stabilized subnanometric Ir clusters in MWW zeolite, which are located at the 10MR window connecting the two neighboring 12MR supercages. The size of the subnanometric Ir clusters can be controlled by the post‐synthesis treatments and maintain below 1 nm even after being reduced at 650 °C, which cannot be readily achieved with samples prepared by conventional impregnation methods. The high structure sensitivity, size‐dependence, of catalytic performance in the alkane hydrogenolysis reaction of Ir clusters in the subnanometric regime is evidenced.

Liu, Lichen↗
DOE OSTI2022

Manipulating and Probing Ultrafast Atomic and Molecular Dynamics (Final Report)

This program has focused on the exploration and control of dynamics in atoms, small molecules, clusters, and micro- or nano-structures following ultrafast excitation and/or driven by strong oscillating fields. In our principal experiments, gas phase atoms and molecules were exposed to short pulses of electromagnetic radiation with frequencies ranging from THz into the XUV spectral regions, and with durations from picoseconds to attoseconds. The pulses coherently induce and/or probe dynamics in the electronic, vibrational, and rotational degrees of freedom of the targets. The overarching goal of the various projects has been to exploit strong-field processes and/or implement novel ultrafast techniques for manipulating and probing coherent electronic and nuclear motion. Typically, the relevant system evolution occurs over attosecond to picosecond timescales. In doing so, we have gained a more complete picture of correlated multi-particle dynamics in atoms, molecules, and other complex systems and expanded the toolbox of useful techniques for manipulating and probing those dynamics. Grant funds were primarily used to: (i) pay salaries and fringe benefits for the PI and postdocs and stipends, tuition, and health care costs for graduate students; (ii) cover travel expenses for the PI, postdocs, and students to attend and participate in professional meetings, conferences, and workshops; and (iii) purchase research materials, supplies, and equipment required for experiments. The research resulted in the publication of 24 peer reviewed articles (including 1 in Nature Physics, 2 in Nature Communications, 7 in Physical Review Letters, and 12 in Physical Review A), and 4 PhD dissertations. The specific results from different funding periods are summarized separately in the main report.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2020

Genesis of the periodic lattice distortions in the charge density wave state of 2 H- TaSe 2

Using high-energy x-ray diffraction and large-scale three-dimensonal structure modeling, we reveal the evolution of local lattice distortions in the archetypal charge density wave (CDW) system 2 H- TaSe 2 as it is cooled from its normal state above room temperature down to temperature where Ta atoms form a long-range ordered superstructure. In particular, we find that the structure is formed via a gradual in-plane clustering of Ta atoms exhibiting unusually short bonding distances already near room temperature, and not via a cooperative distortion of Ta atomic planes taking place at the critical ordering temperature. Our findings clarify the debated local symmetry and magnitude of the periodic lattice distortions in the CDW state of 2 H- TaSe 2 , and emphasize the role of locally correlated lattice distortions as a precursor of CDWs in low-dimensional solids. Further, we demonstrate an efficient experimental approach to study them.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H5ClO6 by Materials Project

H5O2(H2O)4(HClO4)2H5O6ClClO4 crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one molecular hydrogen;dihydrate molecule, four water molecules, one ClO4 cluster, one H5O6Cl cluster, and two HClO4 clusters. In the 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 1.47 Å. In the second O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.47 Å. In the third O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.47 Å. In the fourth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In the H5O6Cl cluster, there are five inequivalent H sites. In the first H site, H is bonded in a single-bond geometry to two O atoms. There is one shorter (1.00 Å) and one longer (1.71 Å) H–O bond length. In the second H site, H is bonded in a linear geometry to two O atoms. There is one shorter (1.20 Å) and one longer (1.24 Å) H–O bond length. In the third H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.99 Å. In the fourth H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.99 Å. In the fifth H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.98 Å. There are six inequivalent O sites. In the first O site, O is bonded in a distorted 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 distorted bent 120 degrees geometry to one H and one Cl atom. The O–Cl bond length is 1.47 Å. In the third O site, O is bonded in a trigonal non-coplanar geometry to three H atoms. In the fourth O site, O is bonded in a trigonal non-coplanar geometry to three H atoms. In the fifth 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 sixth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.45 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In one of the HClO4 clusters, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 1.00 Å. 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 1.43 Å. In the second O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.44 Å. In the third O site, O is bonded in a distorted water-like geometry to one H and one Cl atom. The O–Cl bond length is 1.63 Å. In the fourth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.43 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In one of the HClO4 clusters, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 1.00 Å. 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 1.43 Å. In the second O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.43 Å. In the third O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.43 Å. In the fourth O site, O is bonded in a distorted water-like geometry to one H and one Cl atom. The O–Cl bond length is 1.64 Å. Cl is bonded in a tetrahedral geometry to four O atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Metal-organic frameworks for the adsorption and catalytic transformations of carbon dioxide

Novel crystalline porous materials known as metal-organic frameworks (MOFs) and methods for their synthesis are provided herein. The MOFs include a M6(μ3-OH)8(OH)8(μ2,η2-(O2C)2cyclam)8 cluster, and a metal atom coordinated to the one or more cyclam of the cluster, wherein M is Zr or Hf, and the metal atom is any one of Cu, Ni, Cr, Ru, Co, and Gd. The MOFs can be used as an adsorbent, alone or in a medium with other components, of CO2. The MOFs can also be used as a catalyst for the transformation of CO2 and epoxides to cyclic carbonates. The MOFs can also be used in the electrochemical catalytic reduction of CO2. The MOFs can also be used for photocatalytic CO2 reduction for the production of carbon-based fossil fuels. The MOFs can also be used for light-induced nitric oxide (NO) release. The MOFs can also be used as magnetic resonance imaging (MRI) agents.

Morris, Amanda Jean↗
DOE OSTI2020

Materials Data on CoC12N8(ClO5)2 by Materials Project

CoO4(C5N4)2(CO2)2(ClO)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two formic acid molecules, two C5N4 clusters, one ClO cluster, and one CoO4 cluster. In each C5N4 cluster, there are five inequivalent C+3.67+ sites. In the first C+3.67+ site, C+3.67+ is bonded in a single-bond geometry to one N3- atom. The C–N bond length is 1.30 Å. In the second C+3.67+ site, C+3.67+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.32 Å) and one longer (1.42 Å) C–N bond length. In the third C+3.67+ site, C+3.67+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.39 Å) and one longer (1.58 Å) C–N bond length. In the fourth C+3.67+ site, C+3.67+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.32 Å) and one longer (1.40 Å) C–N bond length. In the fifth C+3.67+ site, C+3.67+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.35 Å) and one longer (1.38 Å) C–N bond length. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded in a bent 120 degrees geometry to two C+3.67+ atoms. In the second N3- site, N3- is bonded in a bent 120 degrees geometry to two C+3.67+ atoms. In the third N3- site, N3- is bonded in a 3-coordinate geometry to three C+3.67+ atoms. In the fourth N3- site, N3- is bonded in a water-like geometry to two C+3.67+ atoms. In the ClO cluster, O2- is bonded in a distorted L-shaped geometry to two equivalent Cl1- atoms. There is one shorter (1.56 Å) and one longer (2.33 Å) O–Cl bond length. Cl1- is bonded in a 2-coordinate geometry to two equivalent O2- atoms. In the CoO4 cluster, Co2+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.64 Å) and two longer (1.88 Å) Co–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Co2+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Co2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H22RuN7(ClO2)4 by Materials Project

(RuN3H6)2(NH4)2(N3H12Cl)2(ClO4)4Cl2 crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two ammonium molecules, two hydrochloric acid molecules, four ClO4 clusters, two N3H12Cl clusters, and two RuN3H6 clusters. In each ClO4 cluster, there are three 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 1.47 Å. In the third O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.47 Å. Cl1- is bonded in a tetrahedral geometry to four O2- atoms. In each N3H12Cl cluster, there are two inequivalent N1- sites. In the first N1- site, N1- is bonded in a tetrahedral geometry to four H1+ atoms. There is three shorter (1.03 Å) and one longer (1.06 Å) N–H bond length. In the second N1- site, N1- is bonded in a tetrahedral geometry to four H1+ atoms. There is three shorter (1.03 Å) and one longer (1.07 Å) N–H bond length. There are seven inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N1- and one Cl1- atom. The H–Cl bond length is 2.07 Å. 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- and one Cl1- atom. The H–Cl bond length is 1.94 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N1- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one N1- atom. Cl1- is bonded in a distorted single-bond geometry to three H1+ atoms. In each RuN3H6 cluster, Ru5+ is bonded in a trigonal non-coplanar geometry to three N1- atoms. There is two shorter (1.88 Å) and one longer (1.94 Å) Ru–N bond length. There are two inequivalent N1- sites. In the first N1- site, N1- is bonded in a distorted trigonal planar geometry to one Ru5+ and two H1+ atoms. Both N–H bond lengths are 1.03 Å. In the second N1- site, N1- is bonded in a distorted trigonal non-coplanar geometry to one Ru5+ and two equivalent H1+ atoms. Both 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.

36 MATERIALS SCIENCE↗
DOE OSTI2020

A new non-diffusional gas bubble production route in used nuclear fuel: Implications for fission gas release, cladding corrosion, and next generation fuel design

The relationship between noble metal phase particles and fission gas bubble production in used nuclear fuel is described. The majority of Te atoms within noble metal phase undergo radioactive decay to form stable Xe within a few hours after particle formation. This results in the production of clusters of Xe atoms contained within the solid metal matrix exhibiting an equivalent gas bubble pressure approaching 1 GPa. These high pressure bubbles are stabilized by the UO2 within the bulk of the fuel. However, when these bubbles form near the fuel / cladding interface, in combination with local and temporal damage caused by fission recoil, they are capable of overcoming the fracture strength of the UO2 and rupturing catastrophically. The force of the resulting bubble rupture is sufficient to eject noble metal phase particles several microns into the cladding. This proposed mechanism explains the observance of noble metal phase in cladding and is consistent with a host of morphological features found near the fuel / cladding interface.

Schwantes, Jon M.↗
DOE OSTI2022

Atomic structure and Mott nature of the insulating charge density wave phase of 1T-TaS 2

Here, using x-ray pair distribution function (PDF) analysis and computer modeling, we explore structure models for the complex charge density wave (CDW) phases of layered 1T-TaS 2 that both well capture their atomic-level features and are amenable to electronic structure calculations. The models give the most probable position of constituent atoms in terms of 3D repetitive unit cells comprising a minimum number of Ta–S layers. Structure modeling results confirm the emergence of star-of-David (SD) like clusters of Ta atoms in the high-temperature incommensurate (IC) CDW phase and show that, contrary to the suggestions of recent studies, the low-temperature commensurate (C) CDW phase expands upon cooling thus reducing lattice strain. The C-CDW phase is also found to preserve the stacking sequence of Ta–S layers found in the room temperature, nearly commensurate (NC) CDW phase to a large extent. DFT based on the PDF refined model shows that bulk C-CDW 1T-TaS 2 also preserves the insulating state of individual layers of SD clusters, favoring the Mott physics description of the metal-to-insulator (NC-CDW to C-CDW) phase transition in 1T-TaS 2 . Our work highlights the importance of using precise crystal structure models in determining the nature of electronic phases in complex materials.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2020

Materials Data on TaP2NCl12 by Materials Project

TaCl6P2NCl6 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of four P2NCl6 clusters and four TaCl6 clusters. In each P2NCl6 cluster, P5+ is bonded to one N3- and three Cl1- atoms to form corner-sharing PNCl3 tetrahedra. The P–N bond length is 1.57 Å. There is one shorter (1.97 Å) and two longer (1.98 Å) P–Cl bond length. N3- is bonded in a bent 150 degrees geometry to two equivalent P5+ atoms. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In each TaCl6 cluster, Ta5+ is bonded in an octahedral geometry to six Cl1- atoms. There are two shorter (2.37 Å) and four longer (2.38 Å) Ta–Cl bond lengths. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Ta5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SbAsH6(CF4)2 by Materials Project

AsH6(CF)2SbF6 crystallizes in the orthorhombic Ibca space group. The structure is zero-dimensional and consists of eight AsH6(CF)2 clusters and eight SbF6 clusters. In each AsH6(CF)2 cluster, C4+ is bonded to one As3- and three H1+ atoms to form distorted corner-sharing CAsH3 tetrahedra. The C–As bond length is 1.91 Å. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. As3- is bonded in a distorted tetrahedral geometry to two equivalent C4+ and two equivalent F1- atoms. Both As–F bond lengths are 1.73 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. F1- is bonded in a single-bond geometry to one As3- atom. In each SbF6 cluster, Sb3- is bonded in an octahedral geometry to six F1- atoms. There are a spread of Sb–F bond distances ranging from 1.91–1.94 Å. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Sb3- atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Sb3- atom. In the third F1- site, F1- is bonded in a single-bond geometry to one Sb3- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Os2Xe(O3F5)2 by Materials Project

XeF5Os2O6F5 crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four Os2O6F5 clusters and four XeF5 clusters. In each Os2O6F5 cluster, Os is bonded to three O and three F atoms to form distorted corner-sharing OsO3F3 octahedra. The corner-sharing octahedral tilt angles are 24°. There is two shorter (1.71 Å) and one longer (1.72 Å) Os–O bond length. There are a spread of Os–F bond distances ranging from 2.00–2.17 Å. There are three inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Os atom. In the second O site, O is bonded in a single-bond geometry to one Os atom. In the third O site, O is bonded in a single-bond geometry to one Os atom. There are three inequivalent F sites. In the first F site, F is bonded in a bent 150 degrees geometry to two equivalent Os atoms. In the second F site, F is bonded in a single-bond geometry to one Os atom. In the third F site, F is bonded in a single-bond geometry to one Os atom. In each XeF5 cluster, Xe is bonded in a distorted square pyramidal geometry to five F atoms. There is three shorter (1.98 Å) and two longer (1.99 Å) Xe–F bond length. There are four 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.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AsS by Materials Project

SAs crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of two $l^{1}-arsanylsulfanylarsenic molecules, two arsenic molecules, two arsinothious acid (9ci) molecules, two As4S5 clusters, one As5S7 cluster, and one SAs cluster. In each As4S5 cluster, there are four inequivalent As2+ sites. In the first As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.23 Å. In the second As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.31 Å. In the third As2+ site, As2+ is bonded in a distorted linear geometry to two S2- atoms. There are one shorter (2.38 Å) and one longer (2.85 Å) As–S bond lengths. In the fourth As2+ site, As2+ is bonded in an L-shaped geometry to two S2- atoms. There are one shorter (2.29 Å) and one longer (2.31 Å) As–S bond lengths. There are five inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted bent 120 degrees geometry to one As2+ and one S2- atom. The S–S bond length is 2.00 Å. In the second S2- site, S2- is bonded in a bent 120 degrees geometry to two As2+ atoms. In the third S2- site, S2- is bonded in a water-like geometry to one As2+ and one S2- atom. The S–S bond length is 2.03 Å. In the fourth S2- site, S2- is bonded in a distorted L-shaped geometry to one As2+ and one S2- atom. In the fifth S2- site, S2- is bonded in a distorted water-like geometry to one As2+ and one S2- atom. In the As5S7 cluster, there are five inequivalent As2+ sites. In the first As2+ site, As2+ is bonded in an L-shaped geometry to two S2- atoms. There are one shorter (2.27 Å) and one longer (2.41 Å) As–S bond lengths. In the second As2+ site, As2+ is bonded in a distorted single-bond geometry to two S2- atoms. There are one shorter (2.35 Å) and one longer (2.98 Å) As–S bond lengths. In the third As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.30 Å. In the fourth As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.31 Å. In the fifth As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.35 Å. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted bent 120 degrees geometry to one As2+ and one S2- atom. The S–S bond length is 1.99 Å. In the second S2- site, S2- is bonded in a distorted water-like geometry to one As2+ and one S2- atom. The S–S bond length is 2.04 Å. In the third S2- site, S2- is bonded in a water-like geometry to one As2+ and one S2- atom. In the fourth S2- site, S2- is bonded in a bent 120 degrees geometry to one As2+ and one S2- atom. The S–S bond length is 2.01 Å. In the fifth S2- site, S2- is bonded in a distorted water-like geometry to one As2+ and one S2- atom. In the sixth S2- site, S2- is bonded in a 3-coordinate geometry to two As2+ and one S2- atom. The S–S bond length is 2.18 Å. In the seventh S2- site, S2- is bonded in a water-like geometry to two S2- atoms. In the SAs cluster, there are three inequivalent As2+ sites. In the first As2+ site, As2+ is bonded in an L-shaped geometry to two S2- atoms. There are one shorter (2.29 Å) and one longer (2.32 Å) As–S bond lengths. In the second As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.30 Å. In the third As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.23 Å. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a bent 120 degrees geometry to two As2+ atoms. In the second S2- site, S2- is bonded in a distorted water-like geometry to one As2+ and one S2- atom. The S–S bond length is 2.03 Å. In the third S2- site, S2- is bonded in a distorted water-like geometry to one As2+ and one S2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AsS by Materials Project

SAs crystallizes in the triclinic P1 space group. The structure is one-dimensional and consists of two arsenic compounds molecules; one As4S3 cluster; one SAs cluster; one SSAs cluster; one As3S4 ribbon oriented in the (1, 0, 0) direction; and two SAs ribbons oriented in the (1, 0, 0) direction. In the As4S3 cluster, there are four inequivalent As2+ sites. In the first As2+ site, As2+ is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.26 Å) and one longer (2.27 Å) As–S bond lengths. In the second As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.28 Å. In the third As2+ site, As2+ is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.28 Å) and one longer (2.29 Å) As–S bond lengths. In the fourth As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.26 Å. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to two As2+ atoms. In the second S2- site, S2- is bonded in a bent 120 degrees geometry to two As2+ atoms. In the third S2- site, S2- is bonded in a bent 120 degrees geometry to two As2+ atoms. In the SAs cluster, there are two inequivalent As2+ sites. In the first As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.31 Å. In the second As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.32 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted water-like geometry to one As2+ and one S2- atom. The S–S bond length is 2.09 Å. In the second S2- site, S2- is bonded in a distorted water-like geometry to one As2+ and one S2- atom. In the SSAs cluster, there are two inequivalent As2+ sites. In the first As2+ site, As2+ is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.30 Å) and one longer (2.35 Å) As–S bond lengths. In the second As2+ site, As2+ is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.29 Å) and one longer (2.35 Å) As–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a water-like geometry to two As2+ atoms. In the second S2- site, S2- is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.05 Å) and one longer (2.06 Å) S–S bond lengths. In the third S2- site, S2- is bonded in a distorted water-like geometry to one As2+ and one S2- atom. In the fourth S2- site, S2- is bonded in a distorted water-like geometry to one As2+ and one S2- atom. In the As3S4 ribbon, there are three inequivalent As2+ sites. In the first As2+ site, As2+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are a spread of As–S bond distances ranging from 2.25–2.36 Å. In the second As2+ site, As2+ is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.26 Å) and one longer (2.33 Å) As–S bond lengths. In the third As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.28 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted water-like geometry to one As2+ and one S2- atom. The S–S bond length is 2.04 Å. In the second S2- site, S2- is bonded in a distorted water-like geometry to one As2+ and one S2- atom. In the third S2- site, S2- is bonded in a water-like geometry to two As2+ atoms. In the fourth S2- site, S2- is bonded in a water-like geometry to two As2+ atoms. In one of the SAs ribbons, there are five inequivalent As2+ sites. In the first As2+ site, As2+ is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.26 Å) and one longer (2.30 Å) As–S bond lengths. In the second As2+ site, As2+ is bonded in a 3-coordinate geometry to three S2- atoms. There are a spread of As–S bond distances ranging from 2.11–2.86 Å. In the third As2+ site, As2+ is bonded in a distorted T-shaped geometry to three S2- atoms. There are a spread of As–S bond distances ranging from 2.28–2.32 Å. In the fourth As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.31 Å. In the fifth As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.28 Å. There are five inequivalent S2- sites. In the first S2- site, S2- is bonded in a single-bond geometry to one As2+ atom. In the second S2- site, S2- is bonded in a water-like geometry to two As2+ atoms. In the third S2- site, S2- is bonded in a water-like geometry to two As2+ atoms. In the fourth S2- site, S2- is bonded in a water-like geometry to two As2+ atoms. In the fifth S2- site, S2- is bonded in a 3-coordinate geometry to three As2+ atoms. In one of the SAs ribbons, there are six inequivalent As2+ sites. In the first As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.31 Å. In the second As2+ site, As2+ is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.27 Å) and one longer (2.34 Å) As–S bond lengths. In the third As2+ site, As2+ is bonded in a distorted trigonal non-coplanar geometry to three S2- atoms. There are a spread of As–S bond distances ranging from 2.28–2.33 Å. In the fourth As2+ site, As2+ is bonded in a single-bond geometry to one S2- atom. The As–S bond length is 2.27 Å. In the fifth As2+ site, As2+ is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.25 Å) and one longer (2.27 Å) As–S bond lengths. In the sixth As2+ site, As2+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are a spread of As–S bond distances ranging from 2.28–2.30 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a bent 120 degrees geometry to two As2+ atoms. In the second S2- site, S2- is bonded in a water-like geometry to two As2+ atoms. In the third S2- site, S2- is bonded in a water-like geometry to two As2+ atoms. In the fourth S2- site, S2- is bonded in a bent 120 degrees geometry to two As2+ atoms. In the fifth S2- site, S2- is bonded in a water-like geometry to two As2+ atoms. In the sixth S2- site, S2- is bonded in a water-like geometry to two As2+ atoms.

36 MATERIALS SCIENCE↗