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All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Distinct Clinical Impact and Biological Function of Angiopoietin and Angiopoietin-like Proteins in Human Breast Cancer

Secreted angiopoietin/angiopoietin-like (ANGPT/ANGPTL) proteins are involved in many biological processes. However, the role of these proteins in human breast cancers (BCs) remains largely unclear. Here, we conducted integrated omics analyses to evaluate the clinical impact of ANGPT/ANGPTL proteins and to elucidate their biological functions. In BCs, we identified rare mutations in ANGPT/ANGPTL genes, frequent gains of ANGPT1, ANGPT4, and ANGPTL1, and frequent losses of ANGPT2, ANGPTL5, and ANGPTL7, but observed that ANGPTL1, 2, and 4 were robustly downregulated in multiple datasets. The expression levels of ANGPTL1, 5, and 8 were positively correlated with overall survival (OS), while the expression levels of ANGPTL4 were negatively correlated with OS. Additionally, the expression levels of ANGPTL1 and 7 were positively correlated with distant metastasis-free survival (DMFS), while the expression levels of ANGPT2 and ANGPTL4 were negatively correlated with DMFS. The prognostic impacts of ANGPT/ANGPTL genes depended on the molecular subtypes and on clinical factors. We discovered that various ANGPT/ANGPTL genes were co-expressed with various genes involved in different pathways. Finally, with the exception of ANGPTL3, the remaining genes showed significant correlations with cancer-associated fibroblasts, endothelial cells, and microenvironment score, whereas only ANGPTL6 was significantly correlated with immune score. Our findings provide strong evidence for the distinct clinical impact and biological function of ANGPT/ANGPTL proteins, but the question of whether some of them could be potential therapeutic targets still needs further investigation in BCs.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2020

Reaching 1.5 and 2.0 °C global surface temperature targets using stratospheric aerosol geoengineering

A new set of stratospheric aerosol geoengineering (SAG) model experiments has been performed with Community Earth System Model version 2 (CESM2) with the Whole Atmosphere Community Climate Model (WACCM6) that are based on the Coupled Model Intercomparison Project phase 6 (CMIP6) overshoot scenario (SSP5-34-OS) as a baseline scenario to limit global warming to 1.5 or 2.0 °C above 1850–1900 conditions. The overshoot scenario allows us to applying a peak-shaving scenario that reduces the needed duration and amount of SAG application compared to a high forcing scenario. In addition, a feedback algorithm identifies the needed amount of sulfur dioxide injections in the stratosphere at four pre-defined latitudes, 30 °N, 15 °N, 15 °S, and 30 °S, to reach three surface temperature targets: global mean temperature, and interhemispheric and pole-to-Equator temperature gradients. These targets further help to reduce side effects, including overcooling in the tropics, warming of high latitudes, and large shifts in precipitation patterns. These experiments are therefore relevant for investigating the impacts on society and ecosystems. Comparisons to SAG simulations based on a high emission pathway baseline scenario (SSP5-85) are also performed to investigate the dependency of impacts using different injection amounts to offset surface warming by SAG. We find that changes from present-day conditions around 2020 in some variables depend strongly on the defined temperature target (1.5 °C vs. 2.0 °C). These include surface air temperature and related impacts, the Atlantic Meridional Overturning Circulation, which impacts ocean net primary productivity, and changes in ice sheet surface mass balance, which impacts sea level rise. Others, including global precipitation changes and the recovery of the Antarctic ozone hole, depend strongly on the amount of SAG application. Furthermore, land net primary productivity as well as ocean acidification depend mostly on the global atmospheric CO 2 concentration and therefore the baseline scenario. Multi-model comparisons of experiments that include strong mitigation and carbon dioxide removal with some SAG application are proposed to assess the robustness of impacts on societies and ecosystems.

42 ENGINEERING↗
DOE OSTI2020

Materials Data on Eu2B5Os3 by Materials Project

Eu2Os3B5 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. Eu3+ is bonded in a 2-coordinate geometry to two equivalent Os1- and four B+0.60- atoms. There are one shorter (3.18 Å) and one longer (3.36 Å) Eu–Os bond lengths. There are a spread of Eu–B bond distances ranging from 2.72–3.03 Å. There are two inequivalent Os1- sites. In the first Os1- site, Os1- is bonded in a 5-coordinate geometry to five B+0.60- atoms. There are a spread of Os–B bond distances ranging from 1.98–2.26 Å. In the second Os1- site, Os1- is bonded in a 6-coordinate geometry to four equivalent Eu3+ and six B+0.60- atoms. There are a spread of Os–B bond distances ranging from 2.18–2.25 Å. There are three inequivalent B+0.60- sites. In the first B+0.60- site, B+0.60- is bonded to four equivalent Eu3+ and two equivalent Os1- atoms to form edge-sharing BEu4Os2 octahedra. In the second B+0.60- site, B+0.60- is bonded in a 5-coordinate geometry to four Os1- and one B+0.60- atom. The B–B bond length is 1.74 Å. In the third B+0.60- site, B+0.60- is bonded in a 7-coordinate geometry to two equivalent Eu3+, three Os1-, and two B+0.60- atoms. The B–B bond length is 1.68 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cs2La10Os2I17 by Materials Project

Cs2La10Os2I17 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Cs is bonded in a 12-coordinate geometry to twelve I atoms. There are a spread of Cs–I bond distances ranging from 4.25–4.61 Å. There are four inequivalent La sites. In the first La site, La is bonded to one Os and five I atoms to form a mixture of corner and edge-sharing LaOsI5 octahedra. The corner-sharing octahedra tilt angles range from 1–9°. The La–Os bond length is 2.89 Å. There are a spread of La–I bond distances ranging from 3.22–3.50 Å. In the second La site, La is bonded to one Os and five I atoms to form distorted LaOsI5 octahedra that share corners with five LaOs2I4 octahedra and edges with five LaOsI5 octahedra. The corner-sharing octahedra tilt angles range from 6–9°. The La–Os bond length is 2.84 Å. There are a spread of La–I bond distances ranging from 3.28–3.52 Å. In the third La site, La is bonded to two equivalent Os and four I atoms to form a mixture of distorted corner and edge-sharing LaOs2I4 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are one shorter (2.86 Å) and one longer (3.02 Å) La–Os bond lengths. There are a spread of La–I bond distances ranging from 3.38–3.55 Å. In the fourth La site, La is bonded to one Os and five I atoms to form a mixture of distorted corner and edge-sharing LaOsI5 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. The La–Os bond length is 2.74 Å. There are a spread of La–I bond distances ranging from 3.26–3.52 Å. Os is bonded to six La atoms to form edge-sharing OsLa6 octahedra. There are six inequivalent I sites. In the first I site, I is bonded in a distorted T-shaped geometry to one Cs and three La atoms. In the second I site, I is bonded in a distorted T-shaped geometry to two equivalent Cs and three La atoms. In the third I site, I is bonded in a 4-coordinate geometry to one Cs and three La atoms. In the fourth I site, I is bonded in a 3-coordinate geometry to two equivalent Cs and three La atoms. In the fifth I site, I is bonded in a distorted square co-planar geometry to four La atoms. In the sixth I site, I is bonded in a 2-coordinate geometry to two equivalent Cs and two La atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Gd3OsO7 by Materials Project

Gd3OsO7 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Gd3+ sites. In the first Gd3+ site, Gd3+ is bonded to seven O2- atoms to form distorted GdO7 pentagonal bipyramids that share corners with two equivalent OsO6 octahedra, corners with three equivalent GdO7 pentagonal bipyramids, edges with two equivalent OsO6 octahedra, and edges with two equivalent GdO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 39°. There are a spread of Gd–O bond distances ranging from 2.26–2.63 Å. In the second Gd3+ site, Gd3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.35 Å) and four longer (2.69 Å) Gd–O bond lengths. Os5+ is bonded to six O2- atoms to form OsO6 octahedra that share corners with two equivalent OsO6 octahedra, corners with four equivalent GdO7 pentagonal bipyramids, and edges with four equivalent GdO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 34°. There is two shorter (1.95 Å) and four longer (1.99 Å) Os–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Gd3+ and one Os5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Gd3+ and two equivalent Os5+ atoms. In the third O2- site, O2- is bonded to four Gd3+ atoms to form a mixture of edge and corner-sharing OGd4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Computational Investigations of the Reactivity of Metalloporphyrins for Ammonia Oxidation

Density functional theory and molecular dynamics simulations were used to assess the ability of tetraphenylporphyrin (TPP)M complexes (where M = Cr, Mn, Fe, Co, Ni, Mo, Ru, W, and Os) to coordinate and weaken the N-H bonds of ammonia, as well as their reactivity towards N-N bond formation for N 2 generation. Compared to other metalloporphyrins, bis-ammonia complexes (TPP)Mo(NH 3 ) 2 and (TPP)W(NH 3 ) 2 exhibit low and level N-H BDFEs due to a stabilized (TPP)M(NH 3 )(NH) intermediate by multiple metal-ligand bonding. These results resemble those previously obtained for polypyridyl metal complexes, suggesting that broad trends in reactivity towards N-H bond cleavage are more metal-dependent rather than ligand-dependent for a metal in a nitrogen pseudo-octahedral environment. We investigated N-N bond formation via NH 3 nucleophilic attack on M-NH and M-N intermediates, compared to bimolecular coupling of M-NH x intermediates. We evaluated the reactivity of (TPP)Fe(NH 3 ) 2 towards N-N bond formation via a hydrazine pathway, and found amide-amide coupling to form a bridged hydrazido complex to be the most favorable pathway for N-N bond formation. Further investigation of possible N-N bond formation pathways by reaction with NH 3 led us to identify a possible Fe III -•NH species with significant aminyl character that bypasses the nucleophilic attack of NH 3 and that promotes homolytic N-H bond cleavage of ammonia. This reaction forms a Fe-NH 2 moiety and a transient •NH 2 radical that subsequently forms an N-N bond with the Fe-NH 2 moiety to form a (TPP)Fe(NH 3 )(N 2 H 4 ) species. Furthermore, these results indicate the need to evaluate the radical character of imido species and their reactivity towards N-H bond cleavage of ammonia.

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

Materials Data on Lu20Os5I24 by Materials Project

Lu20Os5I24 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of one Lu20Os5I24 ribbon oriented in the (1, 1, 1) direction. there are ten inequivalent Lu sites. In the first Lu site, Lu is bonded in a 5-coordinate geometry to two Os and four I atoms. There are one shorter (2.82 Å) and one longer (2.92 Å) Lu–Os bond lengths. There are a spread of Lu–I bond distances ranging from 3.05–3.79 Å. In the second Lu site, Lu is bonded in a 5-coordinate geometry to two Os and four I atoms. There are one shorter (2.84 Å) and one longer (2.92 Å) Lu–Os bond lengths. There are a spread of Lu–I bond distances ranging from 3.06–3.86 Å. In the third Lu site, Lu is bonded in a 6-coordinate geometry to two Os and four I atoms. Both Lu–Os bond lengths are 2.84 Å. There are a spread of Lu–I bond distances ranging from 3.12–3.44 Å. In the fourth Lu site, Lu is bonded to two Os and three I atoms to form distorted corner-sharing LuOs2I3 trigonal bipyramids. There are one shorter (2.84 Å) and one longer (2.93 Å) Lu–Os bond lengths. There are one shorter (3.05 Å) and two longer (3.14 Å) Lu–I bond lengths. In the fifth Lu site, Lu is bonded in a 5-coordinate geometry to two Os and four I atoms. There are one shorter (2.82 Å) and one longer (2.90 Å) Lu–Os bond lengths. There are a spread of Lu–I bond distances ranging from 3.06–3.83 Å. In the sixth Lu site, Lu is bonded in a 5-coordinate geometry to two Os and four I atoms. There are one shorter (2.83 Å) and one longer (2.84 Å) Lu–Os bond lengths. There are a spread of Lu–I bond distances ranging from 3.11–3.70 Å. In the seventh Lu site, Lu is bonded in a 6-coordinate geometry to two Os and four I atoms. Both Lu–Os bond lengths are 2.81 Å. There are a spread of Lu–I bond distances ranging from 3.11–3.56 Å. In the eighth Lu site, Lu is bonded in a 6-coordinate geometry to two Os and four I atoms. There are one shorter (2.80 Å) and one longer (2.81 Å) Lu–Os bond lengths. There are a spread of Lu–I bond distances ranging from 3.10–3.64 Å. In the ninth Lu site, Lu is bonded in a 6-coordinate geometry to two equivalent Os and four I atoms. Both Lu–Os bond lengths are 2.80 Å. There are a spread of Lu–I bond distances ranging from 3.10–3.41 Å. In the tenth Lu site, Lu is bonded in a 6-coordinate geometry to two equivalent Os and four I atoms. There are one shorter (2.82 Å) and one longer (2.83 Å) Lu–Os bond lengths. There are a spread of Lu–I bond distances ranging from 3.11–3.33 Å. There are three inequivalent Os sites. In the first Os site, Os is bonded in a body-centered cubic geometry to eight Lu atoms. In the second Os site, Os is bonded in a 8-coordinate geometry to eight Lu atoms. In the third Os site, Os is bonded in a 8-coordinate geometry to eight Lu atoms. There are twelve inequivalent I sites. In the first I site, I is bonded in a 2-coordinate geometry to two Lu atoms. In the second I site, I is bonded in a 2-coordinate geometry to two Lu atoms. In the third I site, I is bonded in a 3-coordinate geometry to three Lu atoms. In the fourth I site, I is bonded in a 3-coordinate geometry to three Lu atoms. In the fifth I site, I is bonded in a 3-coordinate geometry to three Lu atoms. In the sixth I site, I is bonded in a 3-coordinate geometry to three Lu atoms. In the seventh I site, I is bonded in a 4-coordinate geometry to four Lu atoms. In the eighth I site, I is bonded in a 4-coordinate geometry to four Lu atoms. In the ninth I site, I is bonded in a 4-coordinate geometry to four Lu atoms. In the tenth I site, I is bonded in a 4-coordinate geometry to four Lu atoms. In the eleventh I site, I is bonded in a 4-coordinate geometry to four Lu atoms. In the twelfth I site, I is bonded in a 4-coordinate geometry to three Lu atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2023

The QUIC Start Guide (v 6.4.7)

There are versions of QUIC for 64-bit Windows, 64-bit Linux, and 64-bit Intel Mac OS X. As compared to earlier 32-bit versions of QUIC, the 64-bit versions allow the QUIC transport and dispersion codes to access greater than 2 GB of RAM and thus larger problems can be run.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2020

Materials Data on Ag13OsO6 by Materials Project

Ag13OsO6 crystallizes in the cubic Fm-3c space group. The structure is three-dimensional. Os1- is bonded in an octahedral geometry to six equivalent O2- atoms. All Os–O bond lengths are 1.92 Å. There are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a cuboctahedral geometry to twelve equivalent Ag1+ atoms. All Ag–Ag bond lengths are 2.84 Å. In the second Ag1+ site, Ag1+ is bonded in a 2-coordinate geometry to one Ag1+ and two equivalent O2- atoms. Both Ag–O bond lengths are 2.51 Å. O2- is bonded in a 1-coordinate geometry to one Os1- and four equivalent Ag1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Y(III) Sorption at the Orthoclase (001) Surface Measured by X-ray Reflectivity

Interactions of heavy metals with charged mineral surfaces control their mobility in the environment. Here, we investigate the adsorption of Y(III) onto the orthoclase (001) basal plane, the former as a representative of rare earth elements and an analogue of trivalent actinides and the latter as a representative of naturally abundant K-feldspar minerals. In this study, we apply in situ high-resolution X-ray reflectivity to determine the sorption capacity and molecular distribution of adsorbed Y species as a function of the Y 3+ concentration, [Y 3+ ], at pH 7 and 5. With [Y 3+ ] ≥ 1 mM at pH 7, we observe an inner-sphere (IS) sorption complex at a distance of ~1.5 Å from the surface and an outer-sphere (OS) complex at 3–4 Å. Based on the adsorption height of the IS complex, a bidentate, binuclear binding mode, in which Y 3+ binds to two terminal oxygens, is proposed. In contrast, mostly OS sorption is observed at pH 5. The observed maximum Y coverage is ~1.3 Y 3+ /A UC (A UC : area of the unit cell = 111.4 Å 2 ) for all the investigated pH values and Y concentrations, which is in the expected range based on the estimated surface charge of orthoclase (001).

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

Materials Data on Tl2OsCBr2OF3 by Materials Project

Os2Tl4COBr4F6CO crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of four formaldehyde molecules and one Os2Tl4COBr4F6 sheet oriented in the (-1, 0, 2) direction. In the Os2Tl4COBr4F6 sheet, there are two inequivalent Os1+ sites. In the first Os1+ site, Os1+ is bonded in a 5-coordinate geometry to two Br1- and three F1- atoms. There are one shorter (2.48 Å) and one longer (2.49 Å) Os–Br bond lengths. There are two shorter (2.02 Å) and one longer (2.12 Å) Os–F bond lengths. In the second Os1+ site, Os1+ is bonded in a 5-coordinate geometry to two Br1- and three F1- atoms. Both Os–Br bond lengths are 2.48 Å. There are a spread of Os–F bond distances ranging from 2.02–2.10 Å. There are four inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a 4-coordinate geometry to four F1- atoms. There are a spread of Tl–F bond distances ranging from 2.66–2.97 Å. In the second Tl1+ site, Tl1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Tl–F bond distances ranging from 2.76–3.10 Å. In the third Tl1+ site, Tl1+ is bonded in a 2-coordinate geometry to two F1- atoms. Both Tl–F bond lengths are 2.91 Å. In the fourth Tl1+ site, Tl1+ is bonded in a 1-coordinate geometry to one O2- and four F1- atoms. The Tl–O bond length is 3.19 Å. There are a spread of Tl–F bond distances ranging from 2.67–2.98 Å. C4+ is bonded in a single-bond geometry to one O2- atom. The C–O bond length is 1.18 Å. O2- is bonded in a distorted single-bond geometry to one Tl1+ and one C4+ atom. There are four inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a distorted single-bond geometry to one Os1+ atom. In the second Br1- site, Br1- is bonded in a distorted single-bond geometry to one Os1+ atom. In the third Br1- site, Br1- is bonded in a 1-coordinate geometry to one Os1+ atom. In the fourth Br1- site, Br1- is bonded in a 1-coordinate geometry to one Os1+ atom. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded in a 4-coordinate geometry to one Os1+ and three Tl1+ atoms. In the second F1- site, F1- is bonded in a distorted single-bond geometry to one Os1+ and three Tl1+ atoms. In the third F1- site, F1- is bonded in a 1-coordinate geometry to one Os1+ and three Tl1+ atoms. In the fourth F1- site, F1- is bonded in a 1-coordinate geometry to one Os1+ and three Tl1+ atoms. In the fifth F1- site, F1- is bonded in a 1-coordinate geometry to one Os1+ and two equivalent Tl1+ atoms. In the sixth F1- site, F1- is bonded in a distorted trigonal non-coplanar geometry to one Os1+ and two Tl1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K15Os7N19 by Materials Project

K15Os7N19 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are sixteen inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of K–N bond distances ranging from 2.77–2.91 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 2.79–3.08 Å. In the third K1+ site, K1+ is bonded to four N3- atoms to form distorted KN4 tetrahedra that share corners with four OsN4 tetrahedra and an edgeedge with one KN6 pentagonal pyramid. There are a spread of K–N bond distances ranging from 2.71–3.05 Å. In the fourth K1+ site, K1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 2.67–3.34 Å. In the fifth K1+ site, K1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of K–N bond distances ranging from 2.68–2.83 Å. In the sixth K1+ site, K1+ is bonded in a 4-coordinate geometry to five N3- atoms. There are a spread of K–N bond distances ranging from 2.74–3.34 Å. In the seventh K1+ site, K1+ is bonded to six N3- atoms to form distorted KN6 pentagonal pyramids that share corners with two OsN4 tetrahedra, an edgeedge with one KN6 pentagonal pyramid, an edgeedge with one KN4 tetrahedra, and edges with three OsN4 tetrahedra. There are a spread of K–N bond distances ranging from 2.73–2.97 Å. In the eighth K1+ site, K1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of K–N bond distances ranging from 2.72–3.10 Å. In the ninth K1+ site, K1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of K–N bond distances ranging from 2.82–3.01 Å. In the tenth K1+ site, K1+ is bonded in a 5-coordinate geometry to five N3- atoms. There are a spread of K–N bond distances ranging from 2.67–3.34 Å. In the eleventh K1+ site, K1+ is bonded in a 3-coordinate geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 2.65–3.45 Å. In the twelfth K1+ site, K1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 2.82–3.29 Å. In the thirteenth K1+ site, K1+ is bonded in a 3-coordinate geometry to five N3- atoms. There are a spread of K–N bond distances ranging from 2.72–3.25 Å. In the fourteenth K1+ site, K1+ is bonded in a 4-coordinate geometry to four N3- atoms. There are a spread of K–N bond distances ranging from 2.59–2.97 Å. In the fifteenth K1+ site, K1+ is bonded to eight N3- atoms to form distorted KN8 hexagonal bipyramids that share corners with two equivalent OsN4 tetrahedra and edges with six OsN4 tetrahedra. There are a spread of K–N bond distances ranging from 2.83–3.49 Å. In the sixteenth K1+ site, K1+ is bonded in a 6-coordinate geometry to six N3- atoms. There are a spread of K–N bond distances ranging from 2.90–3.33 Å. There are seven inequivalent Os6+ sites. In the first Os6+ site, Os6+ is bonded to four N3- atoms to form OsN4 tetrahedra that share a cornercorner with one KN6 pentagonal pyramid, a cornercorner with one KN4 tetrahedra, corners with three OsN4 tetrahedra, and an edgeedge with one KN6 pentagonal pyramid. There are a spread of Os–N bond distances ranging from 1.79–1.99 Å. In the second Os6+ site, Os6+ is bonded to four N3- atoms to form OsN4 tetrahedra that share corners with three OsN4 tetrahedra and an edgeedge with one KN8 hexagonal bipyramid. There are a spread of Os–N bond distances ranging from 1.81–1.92 Å. In the third Os6+ site, Os6+ is bonded to four N3- atoms to form OsN4 tetrahedra that share a cornercorner with one KN8 hexagonal bipyramid, corners with three OsN4 tetrahedra, and an edgeedge with one KN8 hexagonal bipyramid. There are a spread of Os–N bond distances ranging from 1.77–2.01 Å. In the fourth Os6+ site, Os6+ is bonded to four N3- atoms to form OsN4 tetrahedra that share corners with two OsN4 tetrahedra and an edgeedge with one KN8 hexagonal bipyramid. There are a spread of Os–N bond distances ranging from 1.81–1.89 Å. In the fifth Os6+ site, Os6+ is bonded to four N3- atoms to form corner-sharing OsN4 tetrahedra. There are a spread of Os–N bond distances ranging from 1.77–1.96 Å. In the sixth Os6+ site, Os6+ is bonded to four N3- atoms to form OsN4 tetrahedra that share corners with two equivalent KN4 tetrahedra, corners with two OsN4 tetrahedra, and an edgeedge with one KN6 pentagonal pyramid. There is two shorter (1.82 Å) and two longer (1.87 Å) Os–N bond length. In the seventh Os6+ site, Os6+ is bonded to four N3- atoms to form OsN4 tetrahedra that share a cornercorner with one KN6 pentagonal pyramid, a cornercorner with one KN4 tetrahedra, corners with two OsN4 tetrahedra, and an edgeedge with one KN6 pentagonal pyramid. There are a spread of Os–N bond distances ranging from 1.81–1.88 Å. There are nineteen inequivalent N3- sites. In the first N3- site, N3- is bonded in a 6-coordinate geometry to five K1+ and one Os6+ atom. In the second N3- site, N3- is bonded in a 2-coordinate geometry to three K1+ and two Os6+ atoms. In the third N3- site, N3- is bonded in a 6-coordinate geometry to five K1+ and one Os6+ atom. In the fourth N3- site, N3- is bonded in a 4-coordinate geometry to three K1+ and two Os6+ atoms. In the fifth N3- site, N3- is bonded in a 3-coordinate geometry to three K1+ and two Os6+ atoms. In the sixth N3- site, N3- is bonded in a 1-coordinate geometry to five K1+ and one Os6+ atom. In the seventh N3- site, N3- is bonded in a 6-coordinate geometry to five K1+ and one Os6+ atom. In the eighth N3- site, N3- is bonded in a 2-coordinate geometry to two K1+ and two Os6+ atoms. In the ninth N3- site, N3- is bonded in a 1-coordinate geometry to six K1+ and one Os6+ atom. In the tenth N3- site, N3- is bonded in a distorted octahedral geometry to five K1+ and one Os6+ atom. In the eleventh N3- site, N3- is bonded in a 2-coordinate geometry to four K1+ and two Os6+ atoms. In the twelfth N3- site, N3- is bonded in a 4-coordinate geometry to four K1+ and one Os6+ atom. In the thirteenth N3- site, N3- is bonded in a 3-coordinate geometry to four K1+ and two Os6+ atoms. In the fourteenth N3- site, N3- is bonded in a 5-coordinate geometry to four K1+ and two Os6+ atoms. In the fifteenth N3- site, N3- is bonded in a 1-coordinate geometry to five K1+ and one Os6+ atom. In the sixteenth N3- site, N3- is bonded in a 5-coordinate geometry to three K1+ and two Os6+ atoms. In the seventeenth N3- site, N3- is bonded in a 2-coordinate geometry to three K1+ and two Os6+ atoms. In the eighteenth N3- site, N3- is bonded in a 6-coordinate geometry to five K1+ and one Os6+ atom. In the nineteenth N3- site, N3- is bonded in a 1-coordinate geometry to four K1+ and one Os6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Exploring the Links between Structural Distortions, Orbital Ordering, and Multipolar Magnetic Ordering in Double Perovskites Containing Re(VI) and Os(VII)

A combination of high-resolution powder diffraction techniques and solid-state NMR has been employed to explore the links between crystal structure, orbital ordering, and magnetism in three isostructural double perovskites containing transition metal ions with a 5d 1 configuration. In Ba 2 ZnReO 6 , both neutron and synchrotron X-ray powder diffraction data reveal a cubic-to-tetragonal transition at 23 K that breaks the degeneracy of the t 2g orbitals and leads to a pattern of orbital ordering that stabilizes magnetic ordering when the sample is cooled below 16 K. Similar behavior is observed in Ba 2 MgReO 6 , with an orbital ordering temperature of 33 K and a magnetic ordering temperature of 18 K. Prior theoretical works suggest that the pattern of orbital order seen in the P42/mnm space group is needed to stabilize the heavily canted antiferromagnetism of these compounds. Unfortunately, powder diffraction data is not sensitive enough to differentiate between the I4/mmm and P42/mnm structural models, as the distortions are too subtle to be unambiguously identified from either neutron or synchrotron X-ray powder diffraction methods. In contrast, both diffraction and 7 Li NMR data indicate that Ba 2 LiOsO 6 retains the cubic structure down to 1.7 K. The antiferromagnetic ground state and lack of any sign of orbital ordering in Ba 2 LiOsO 6 provide compelling evidence that the electronically driven tetragonal distortion seen in Ba2ZnReO6, and Ba2MgReO6 is intimately linked to the magnetic ordering seen in those compounds. The absence of magnetic reflections in high intensity neutron powder diffraction data collected on Ba 2 MgReO 6 strongly suggests ordering of multipolar moments on Re(VI), likely ferro-octupolar ordering.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Performance of the spin-component-scaled methods for energy bands

The performance of various spin-component-scaled parameterisations is examined for the second-order many-body Green's-function [MBGF(2)] calculations of valence energy bands, taking three of the experimentally well-characterised polymers as examples: polyethylene, polytetrafluoroethylene, and polyacetylene. The parameterisations considered are Grimme's original SCS parameter set, Jung et al.'s original SOS set (retaining the opposite-spin component only), Śmiga et al.'s SCS(IP) set (calibrated specifically for ionization energies), and Śmiga et al.'s SOS(IP) set (calibrated for ionization energies with the opposite-spin component only; implicit in the os-D2 model of Opoku et al.). The SCS(IP) and SOS(IP) parameterisations are found to shift both outer and inner valence bands by up to a few electronvolts away from the experimental data. The original SCS and SOS parameter sets do not improve upon, but largely maintain the accuracy of the unscaled MBGF(2) methods. Given that the SOS-MBGF(2) method can be implemented in a quartic-scaling algorithm (for all roots), it is most promising for solid-state applications. Furthermore this observation is consistent with the success of the quartic-scaling GW methods without the vertex correction based on a density-functional theory reference.

Green’s-function theory↗
DOE OSTI2020

Synthesis, Crystal Structure, and Cooperative 3d–5d Magnetism in Rock Salt Type Li 4 NiOsO 6 and Li 3 Ni 2 OsO 6

Two new transition metal oxides with the nominal chemical compositions of Li 4 NiOsO 6 and Li 3 Ni 2 OsO 6 were successfully synthesized. Both compounds crystallize in an ordered rock salt structure type in the monoclinic C2/m space group. The crystal structures were determined using both synchrotron X-ray and time-of-flight neutron, powder diffraction data. In both phases, Ni2+ ions are present while oxidation states of osmium are +6 and +5 in Li 4 NiOsO 6 and Li 3 Ni 2 OsO 6 , respectively. Ni2+ ions in the hypothetical fully ordered phase form a honeycomb arrangement in the ab crystallographic plane and these hexagons are centered by osmium ions. Furthermore, the magnetic layers are separated along the c axis by the octahedra, which are centered by Li+ (or Li+/Ni 2+ , depending on the chemical compositions). Crystal structure refinements reveal that there is some degree of mixed occupancy in cationic positions. Temperature dependent magnetic susceptibility data for both phases show ferrimagnetic transitions with predominant antiferromagnetic (AFM) interactions among 3d electrons of nickel and Sd electrons of osmium. Iso-thermal magnetization loops as a function of the applied magnetic field below the transition temperatures confirm the ferrimagnetic nature in magnetic transitions. Temperature dependent heat capacity data, however, did not exhibit any anomaly in either phase, indicating the absence of long-range magnetic ordering. The lack of long-range order for both Os 5+ and Os 6+ -based compounds was also confirmed by low temperature neutron diffraction data down to 10 K. Temperature dependent AC magnetic susceptibility data in various frequencies for both samples indicate that Li 4 NiOsO 6 exhibits spin-glass-like behavior, while the transition temperature for Li 3 Ni 2 OsO 6 is nearly frequency independent.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Breaking the Brønsted–Evans–Polanyi Relation with Dual-Metal Sites

Linear scaling relationships impose inherent limitations on catalyst activity; the Brønsted−Evans−Polanyi (BEP) relation, which correlates activation and reaction energies, is a prominent example. Here we report a dual-metal site catalyst (DMSC) on ceria that breaks the BEP relation for C−C coupling of methyl intermediates an elementary step in methane coupling to form ethane. The DMSC structure on CeO 2 (111) was discovered by density-functional theory (DFT) structural exploration and confirmed to be stable via ab initio thermodynamics and ab initio molecular dynamics. Homonuclear and heteronuclear DMSCs of Ni, Pd, Pt, Fe, Ru, Os, Co, Rh, and Ir (45 pairs in total) were examined for methyl affinity and methyl−methyl coupling activation energy. We found that many heteronuclear DMSCs break the BEP linear scaling due to a mixed low-affinity/high-affinity coadsorption of the two methyl groups, decoupling the step responsible for the activation energy (E a ) at the low-affinity site from the overall reaction energy (ΔE) determined by both sites. This mechanism of breaking the BEP relationship via the DMSCs offers a catalyst design principle for C−C coupling reactions.

Chen, Yiming [Vanderbilt Univ., Nashville, TN (Uni↗
DOE OSTI2020

Materials Data on LuB4Os by Materials Project

LuOsB4 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Lu3+ is bonded in a 2-coordinate geometry to fourteen B+1.50- atoms. There are a spread of Lu–B bond distances ranging from 2.61–2.76 Å. Os3+ is bonded in a 10-coordinate geometry to ten B+1.50- atoms. There are a spread of Os–B bond distances ranging from 2.24–2.41 Å. There are four inequivalent B+1.50- sites. In the first B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to four equivalent Lu3+, two equivalent Os3+, and three B+1.50- atoms. There are a spread of B–B bond distances ranging from 1.74–1.87 Å. In the second B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to four equivalent Lu3+, two equivalent Os3+, and three B+1.50- atoms. The B–B bond length is 1.84 Å. In the third B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to four equivalent Lu3+, two equivalent Os3+, and three B+1.50- atoms. Both B–B bond lengths are 1.73 Å. In the fourth B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to two equivalent Lu3+, four equivalent Os3+, and three B+1.50- atoms. The B–B bond length is 1.73 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YB4Os by Materials Project

YOsB4 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. Y3+ is bonded in a 2-coordinate geometry to fourteen B+1.50- atoms. There are a spread of Y–B bond distances ranging from 2.65–2.78 Å. Os3+ is bonded in a 10-coordinate geometry to ten B+1.50- atoms. There are a spread of Os–B bond distances ranging from 2.26–2.42 Å. There are four inequivalent B+1.50- sites. In the first B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to four equivalent Y3+, two equivalent Os3+, and three B+1.50- atoms. There are a spread of B–B bond distances ranging from 1.75–1.88 Å. In the second B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to four equivalent Y3+, two equivalent Os3+, and three B+1.50- atoms. The B–B bond length is 1.85 Å. In the third B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to four equivalent Y3+, two equivalent Os3+, and three B+1.50- atoms. There is one shorter (1.74 Å) and one longer (1.77 Å) B–B bond length. In the fourth B+1.50- site, B+1.50- is bonded in a 9-coordinate geometry to two equivalent Y3+, four equivalent Os3+, and three B+1.50- atoms. The B–B bond length is 1.72 Å.

36 MATERIALS SCIENCE↗