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At least 91 records · Page 5
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DOE OSTI2020

Materials Data on PPd6 by Materials Project

Pd6P crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four Pd6P clusters. there are six inequivalent Pd sites. In the first Pd site, Pd is bonded in a distorted single-bond geometry to one P atom. The Pd–P bond length is 2.29 Å. In the second Pd site, Pd is bonded in a 1-coordinate geometry to one P atom. The Pd–P bond length is 2.28 Å. In the third Pd site, Pd is bonded in a 1-coordinate geometry to one P atom. The Pd–P bond length is 2.30 Å. In the fourth Pd site, Pd is bonded in a distorted single-bond geometry to one P atom. The Pd–P bond length is 2.29 Å. In the fifth Pd site, Pd is bonded in a distorted single-bond geometry to one P atom. The Pd–P bond length is 2.28 Å. In the sixth Pd site, Pd is bonded in a 1-coordinate geometry to one P atom. The Pd–P bond length is 2.30 Å. P is bonded in a 6-coordinate geometry to six Pd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Breaking C-C Bonds via Electrochemically Mediated Hydrogen Atom Transfer Reactions

Cleaving inert SP3-SP3 carbon-carbon (C-C) bonds selectively remains a major challenge in organic chemistry and a main bottleneck in the chemical upcycling of recalcitrant polyolefin waste. Here, we present an electrochemical strategy using redox mediators to activate and break C-C bonds at room temperature and ambient pressure. Specifically, we use N-hydroxyphthalimide (NHPI) as a redox mediator that undergoes electrochemical oxidation to form the phthalimide-N-oxyl (PINO) radical to initiate hydrogen atom transfer (HAT) reactions with benzylic C-H bonds. The resulting benzylic carbon radical is readily captured by molecular oxygen to form a peroxy radical that decomposes into oxygenated C-C bond-scission fragments. This indirect, mediated approach for Csp3-Csp3 bond cleavage reduces the oxidation potential by > 1.2 V compared to the direct oxidation of the substrate, thereby eliminating deleterious side reactions, such as solvent oxidation, that may occur at high potentials. Studies with a bibenzyl model compound revealed a bifurcated reaction pathway following the initial HAT step. At a bibenzyl conversion of 61.0%, the C-C bond cleavage pathway generates benzaldehyde and benzoic acid products at 38.4% selectivity, and the C-H bond oxygenation pathway leads to 1,2-diphenylethanone and benzil products at 39.2% selectivity. Changes in reaction selectivity were investigated with various model compounds, including bibenzyl, 1,3-diphe-nylpropane, 1,4-diphenylbutane, and their derivatives. Product selectivity is correlated with the C-C bond strength of the reactant, with weaker C-C bonds favoring the C-C bond cleavage pathway. We also evaluated the mediated oxidation of oligo-meric styrene (Mn= 510 Da, OS510) which were converted into oxygenated products. Lastly, proof-of-concept depolymeriza-tion of polystyrene (PS, ~10,000 Da) into oxygenated monomers, dimers, and oligomers was demonstrated using NHPI-mediated oxidation.

benzoic acid↗
DOE OSTI2020

Materials Data on Te6RuBr8 by Materials Project

RuTeTe5Br8 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four ruthenium molecules, four tellurium molecules, and four Te5Br8 clusters. In each Te5Br8 cluster, there are five inequivalent Te1+ sites. In the first Te1+ site, Te1+ is bonded in a single-bond geometry to one Br1- atom. The Te–Br bond length is 3.16 Å. In the second Te1+ site, Te1+ is bonded in a single-bond geometry to one Br1- atom. The Te–Br bond length is 3.04 Å. In the third Te1+ site, Te1+ is bonded in a rectangular see-saw-like geometry to four Br1- atoms. There are a spread of Te–Br bond distances ranging from 2.59–3.05 Å. In the fourth Te1+ site, Te1+ is bonded in a distorted rectangular see-saw-like geometry to four Br1- atoms. There are a spread of Te–Br bond distances ranging from 2.56–3.34 Å. In the fifth Te1+ site, Te1+ is bonded in a T-shaped geometry to three Br1- atoms. There are a spread of Te–Br bond distances ranging from 2.59–2.78 Å. There are eight inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a single-bond geometry to one Te1+ atom. In the second Br1- site, Br1- is bonded in an L-shaped geometry to two Te1+ atoms. In the third Br1- site, Br1- is bonded in a single-bond geometry to one Te1+ atom. In the fourth Br1- site, Br1- is bonded in a distorted L-shaped geometry to two Te1+ atoms. In the fifth Br1- site, Br1- is bonded in a distorted single-bond geometry to two Te1+ atoms. In the sixth Br1- site, Br1- is bonded in a single-bond geometry to one Te1+ atom. In the seventh Br1- site, Br1- is bonded in a 2-coordinate geometry to two Te1+ atoms. In the eighth Br1- site, Br1- is bonded in a 2-coordinate geometry to two Te1+ atoms.

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 Fe11MoC4 by Materials Project

MoFe5C2(Fe3C)2 crystallizes in the monoclinic Pm space group. The structure is two-dimensional and consists of one Fe3C sheet oriented in the (0, 1, 0) direction and one MoFe5C2 sheet oriented in the (0, 1, 0) direction. In the Fe3C sheet, there are four inequivalent Fe sites. In the first Fe site, Fe is bonded in a single-bond geometry to one C atom. The Fe–C bond length is 1.79 Å. In the second Fe site, Fe is bonded in a single-bond geometry to one C atom. The Fe–C bond length is 1.88 Å. In the third Fe site, Fe is bonded in a square co-planar geometry to four C atoms. There are two shorter (2.01 Å) and two longer (2.04 Å) Fe–C bond lengths. In the fourth Fe site, Fe is bonded in a square co-planar geometry to four C atoms. There are a spread of Fe–C bond distances ranging from 1.99–2.04 Å. There are two inequivalent C sites. In the first C site, C is bonded to six Fe atoms to form a mixture of corner and edge-sharing CFe6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second C site, C is bonded to six Fe atoms to form a mixture of corner and edge-sharing CFe6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the MoFe5C2 sheet, Mo is bonded in a square co-planar geometry to four C atoms. There are a spread of Mo–C bond distances ranging from 2.10–2.12 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded in a single-bond geometry to one C atom. The Fe–C bond length is 1.89 Å. In the second Fe site, Fe is bonded in a single-bond geometry to one C atom. The Fe–C bond length is 1.90 Å. In the third Fe site, Fe is bonded in a square co-planar geometry to four C atoms. There are a spread of Fe–C bond distances ranging from 1.92–1.95 Å. There are two inequivalent C sites. In the first C site, C is bonded to two equivalent Mo and four Fe atoms to form a mixture of corner and edge-sharing CFe4Mo2 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the second C site, C is bonded to two equivalent Mo and four Fe atoms to form a mixture of corner and edge-sharing CFe4Mo2 octahedra. The corner-sharing octahedra tilt angles range from 0–1°.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Zero-Valent Palladium Single-Atoms Catalysts Confined in Black Phosphorus for Efficient Semi-Hydrogenation

Single-atom catalysts (SACs) represent a new frontier in heterogeneous catalysis due to their remarkable catalytic properties and maximized atomic utilization. However, single atoms often bond to the support with polarized electron density and thus exhibit a high valence state, limiting their catalytic scopes in many chemical transformations. In this study, it is demonstrated that 2D black phosphorus (BP) acts as giant phosphorus (P) ligand to confine a high density of single atoms (e.g., Pd 1 , Pt 1 ) via atomic layer deposition. Unlike other 2D materials, BP with relatively low electronegativity and buckled structure favors the strong confinement of robust zero-valent palladium SACs in the vacancy site. Metallic Pd 1 /BP SAC shows a highly selective semi-hydrogenation of phenylacetylene toward styrene, distinct from metallic Pd nanoparticles that facilitate the formation of fully hydrogenated products. Density functional theory calculations reveal that Pd atom forms covalent-like bonding with adjacent P atoms, wherein H atoms tend to adsorb, aiding the dissociative adsorption of H 2 . Zero-valent Pd in the confined space favors a larger energy gain for the synthesis of partially hydrogenated product over the fully hydrogenated one. This work provides a new route toward the synthesis of zero-valent SACs on BP for organic transformations.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H3ClO5 by Materials Project

H3OClO4 is alpha Np structured and crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four water molecules and four HClO4 clusters. In each HClO4 cluster, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.99 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 1.43 Å. In the second O site, O is bonded in a distorted water-like geometry to one H and one Cl atom. The O–Cl bond length is 1.66 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. Cl is bonded in a tetrahedral geometry to four O atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HgH12(ClO7)2 by Materials Project

Hg(H2O)6(ClO4)2 crystallizes in the trigonal P-3m1 space group. The structure is zero-dimensional and consists of two ClO4 clusters and one Hg(H2O)6 cluster. In each ClO4 cluster, there are two 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 1.45 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In the Hg(H2O)6 cluster, Hg is bonded in an octahedral geometry to six equivalent O atoms. All Hg–O bond lengths are 2.40 Å. H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.98 Å. O is bonded in a distorted water-like geometry to one Hg and two equivalent H atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H2SO4 by Materials Project

H2SO4 is Protactinium-like structured and crystallizes in the monoclinic Cc space group. The structure is zero-dimensional and consists of four sulfuric acid molecules. there are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. S6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of S–O bond distances ranging from 1.44–1.58 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the second O2- site, O2- is bonded in a distorted water-like geometry to one H1+ and one S6+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one H1+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one S6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H2SO4 by Materials Project

H2SO4 crystallizes in the monoclinic Cc space group. The structure is zero-dimensional and consists of four sulfuric acid molecules. there are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. S6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of S–O bond distances ranging from 1.43–1.59 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one S6+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one H1+ and one S6+ atom. In the third O2- site, O2- is bonded in a water-like geometry to one H1+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one S6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Diamond under extremes

Diamond is, by virtue of the covalent bonding between atoms and the very strong carbon to carbon bonds, the hardest natural material. It has been a fascinating material since its discovery, first as a decorative gem and more recently, for its numerous industrial uses because of its extreme hardness, elastic modulus, and optical transparency. In recent years, it has become a preferred ablator for laser shock experiments, and this has led to its choice as the capsule material for fusion experiments at the National Ignition Facility. Further, this review covers both experimental and computational (including machine learning) advancements in research on diamond subjected extreme conditions of temperature and pressure. The synergy between shock and ramp loading experiments and atomic level simulations is proving to be powerful in advancing our understanding of diamond under extremes.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiH6ClO7 by Materials Project

Li(H2O)3ClO4 crystallizes in the hexagonal P6_3mc space group. The structure is one-dimensional and consists of two ClO4 clusters and one Li(H2O)3 ribbon oriented in the (0, 0, 1) direction. In each ClO4 cluster, there are two 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 1.45 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In the Li(H2O)3 ribbon, Li is bonded to six equivalent O atoms to form face-sharing LiO6 octahedra. All Li–O bond lengths are 2.15 Å. H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.98 Å. O is bonded in a distorted water-like geometry to two equivalent Li and two equivalent H atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HgTe(HO)7 by Materials Project

HgH5TeO6H2O crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of two water molecules and one HgH5TeO6 ribbon oriented in the (0, 1, 1) direction. In the HgH5TeO6 ribbon, Hg1+ is bonded in a distorted single-bond geometry to one O2- atom. The Hg–O bond length is 2.18 Å. There are five inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.64 Å) H–O bond length. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. There are two inequivalent Te6+ sites. In the first Te6+ site, Te6+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Te–O bond distances ranging from 1.93–1.98 Å. In the second Te6+ site, Te6+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Te–O bond distances ranging from 1.90–2.02 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one H1+ and one Te6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to one H1+ and one Te6+ atom. In the third O2- site, O2- is bonded in a distorted water-like geometry to one H1+ and one Te6+ atom. In the fourth O2- site, O2- is bonded in a trigonal planar geometry to one Hg1+, one H1+, and one Te6+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to one H1+ and one Te6+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one H1+ and one Te6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H10C3NClO4 by Materials Project

C3H7NH3ClO4 is Silicon tetrafluoride-derived structured and crystallizes in the monoclinic P2_1/m space group. The structure is zero-dimensional and consists of two trimethylazanium molecules and two ClO4 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 1.46 Å. In the third O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.48 Å. Cl1- is bonded in a tetrahedral geometry to four O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H4NClO4 by Materials Project

NH4ClO4 is Silicon tetrafluoride-derived structured and crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four ammonium molecules and four ClO4 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 1.45 Å. Cl1- is bonded in a tetrahedral geometry to four O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Linear Combination of Atomic Dipoles to Calculate the Bond and Molecular Dipole Moments of Molecules and Molecular Liquids

Here we report a linear combination of atomic dipole (LCAD) method for calculating the bond dipole moments of molecules. We show that the LCAD method reproduces the known molecular dipole moments of small to large molecules with a small error with respect to experimental and benchmark ab initio calculations, and molecular dipole distributions of bulk water that agree with maximally localized Wannier functions. The bond dipole moments derived from LCAD are also chemically interpretable in terms of the trend in bond ionicity in going from neutral to charged molecules. Moreover, the LCAD method accurately captures the influence of electric fields, supported by the correct trend in the change of the dipole moment under a uniform external electric field. The better grounding of bond dipole calculations indicates that it should also serve as a useful approach to bond dipole-field models used in catalysis or to reconstruct the small dipole of a H-terminated graphene flake.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on CSNF5 by Materials Project

CNSF5 is beta Np structured and crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four CNSF5 clusters. C4+ is bonded in a single-bond geometry to one N3+ atom. The C–N bond length is 1.19 Å. N3+ is bonded in a linear geometry to one C4+ and one S2- atom. The N–S bond length is 1.69 Å. S2- is bonded in an octahedral geometry to one N3+ and five F1- atoms. All S–F bond lengths are 1.60 Å. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one S2- atom. In the second F1- site, F1- is bonded in a single-bond geometry to one S2- atom. In the third F1- site, F1- is bonded in a single-bond geometry to one S2- atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one S2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Intramolecular hydrogen bonding analysis

The quasi-atomic orbital (QUAO) bonding analysis is used to study intramolecular hydrogen bonding (IMHB) in salicylic acid and an intermediate that is crucial to the synthesis of aspirin. The bonding analysis rigorously explores IMHB through directly accessing information that is intrinsic to the molecular wave function, thereby bypassing the need for intrinsically biased methods. The variables that affect the strength of IMHB are determined using kinetic bond orders, QUAO populations, and QUAO hybridizations. Important properties include both the interatomic distance between hydrogen and oxygen participating in the IMHB and the hybridization on the oxygen. The bonding analysis further shows that each intramolecular hydrogen bond is a four-electron three-center bond. Here, the bonding analysis is used to understand how aromatic reactivity changes due to the effect of functional groups on the aromatic ring.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗