Materials Data on OsC4(ClO2)2 by Materials Project
OsCl2(CO)4 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of four dichloroosmium molecules and sixteen formaldehyde molecules.
36 MATERIALS SCIENCE↗
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Materials Data on Cs2Ce10Os2I17 by Materials Project
Cs2Ce10Os2I17 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Cs is bonded to twelve I atoms to form CsI12 cuboctahedra that share corners with fourteen CeOs2I4 octahedra, edges with two equivalent CsI12 cuboctahedra, a faceface with one CsI12 cuboctahedra, and faces with six CeOsI5 octahedra. The corner-sharing octahedra tilt angles range from 35–48°. There are a spread of Cs–I bond distances ranging from 4.15–4.48 Å. There are four inequivalent Ce sites. In the first Ce site, Ce is bonded to one Os and five I atoms to form distorted CeOsI5 octahedra that share corners with two equivalent CsI12 cuboctahedra, corners with five CeOs2I4 octahedra, edges with five CeOs2I4 octahedra, and faces with two equivalent CsI12 cuboctahedra. The corner-sharing octahedra tilt angles range from 5–10°. The Ce–Os bond length is 2.78 Å. There are a spread of Ce–I bond distances ranging from 3.22–3.41 Å. In the second Ce site, Ce is bonded to one Os and five I atoms to form distorted CeOsI5 octahedra that share corners with two equivalent CsI12 cuboctahedra, corners with four CeOs2I4 octahedra, edges with five CeOs2I4 octahedra, and faces with two equivalent CsI12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–10°. The Ce–Os bond length is 2.72 Å. There are a spread of Ce–I bond distances ranging from 3.20–3.40 Å. In the third Ce site, Ce is bonded to one Os and five I atoms to form distorted CeOsI5 octahedra that share corners with three equivalent CsI12 cuboctahedra, corners with two CeOsI5 octahedra, edges with six CeOs2I4 octahedra, and a faceface with one CsI12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–9°. The Ce–Os bond length is 2.79 Å. There are a spread of Ce–I bond distances ranging from 3.18–3.42 Å. In the fourth Ce site, Ce is bonded to two equivalent Os and four I atoms to form CeOs2I4 octahedra that share corners with four equivalent CsI12 cuboctahedra, corners with three CeOs2I4 octahedra, and edges with eight CeOs2I4 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are one shorter (2.81 Å) and one longer (2.90 Å) Ce–Os bond lengths. There are a spread of Ce–I bond distances ranging from 3.29–3.46 Å. Os is bonded to six Ce atoms to form edge-sharing OsCe6 octahedra. There are six inequivalent I sites. In the first I site, I is bonded in a 5-coordinate geometry to two equivalent Cs and three Ce atoms. In the second I site, I is bonded in a 5-coordinate geometry to two equivalent Cs and three Ce atoms. In the third I site, I is bonded in a distorted square co-planar geometry to four Ce atoms. In the fourth I site, I is bonded in a distorted rectangular see-saw-like geometry to one Cs and three Ce atoms. In the fifth I site, I is bonded in a 4-coordinate geometry to two equivalent Cs and two Ce atoms. In the sixth I site, I is bonded in a 4-coordinate geometry to one Cs and three Ce atoms.
36 MATERIALS SCIENCE↗
Materials Data on Cs2Pr10Os2I17 by Materials Project
Cs2Pr10Os2I17 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Cs is bonded to twelve I atoms to form distorted CsI12 cuboctahedra that share corners with fourteen PrOsI5 octahedra, edges with two equivalent CsI12 cuboctahedra, a faceface with one CsI12 cuboctahedra, and faces with six PrOsI5 octahedra. The corner-sharing octahedra tilt angles range from 35–48°. There are a spread of Cs–I bond distances ranging from 4.25–4.56 Å. There are four inequivalent Pr sites. In the first Pr site, Pr is bonded to one Os and five I atoms to form PrOsI5 octahedra that share corners with three equivalent CsI12 cuboctahedra, corners with two PrOsI5 octahedra, edges with six PrOsI5 octahedra, and a faceface with one CsI12 cuboctahedra. The corner-sharing octahedra tilt angles range from 2–9°. The Pr–Os bond length is 2.87 Å. There are a spread of Pr–I bond distances ranging from 3.20–3.50 Å. In the second Pr site, Pr is bonded to one Os and five I atoms to form distorted PrOsI5 octahedra that share corners with two equivalent CsI12 cuboctahedra, corners with five PrOs2I4 octahedra, edges with five PrOsI5 octahedra, and faces with two equivalent CsI12 cuboctahedra. The corner-sharing octahedra tilt angles range from 4–10°. The Pr–Os bond length is 2.79 Å. There are a spread of Pr–I bond distances ranging from 3.27–3.51 Å. In the third Pr site, Pr is bonded to two equivalent Os and four I atoms to form PrOs2I4 octahedra that share corners with four equivalent CsI12 cuboctahedra, corners with three PrOsI5 octahedra, and edges with eight PrOsI5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are one shorter (2.87 Å) and one longer (2.95 Å) Pr–Os bond lengths. There are a spread of Pr–I bond distances ranging from 3.36–3.49 Å. In the fourth Pr site, Pr is bonded to one Os and five I atoms to form distorted PrOsI5 octahedra that share corners with two equivalent CsI12 cuboctahedra, corners with four PrOsI5 octahedra, edges with five PrOsI5 octahedra, and faces with two equivalent CsI12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–10°. The Pr–Os bond length is 2.76 Å. There are a spread of Pr–I bond distances ranging from 3.23–3.50 Å. Os is bonded to six Pr atoms to form edge-sharing OsPr6 octahedra. There are six inequivalent I sites. In the first I site, I is bonded in a 3-coordinate geometry to one Cs and three Pr atoms. In the second I site, I is bonded in a distorted T-shaped geometry to two equivalent Cs and three Pr atoms. In the third I site, I is bonded in a 4-coordinate geometry to one Cs and three Pr atoms. In the fourth I site, I is bonded in a 3-coordinate geometry to two equivalent Cs and three Pr atoms. In the fifth I site, I is bonded in a distorted square co-planar geometry to four Pr atoms. In the sixth I site, I is bonded in a 2-coordinate geometry to two equivalent Cs and two Pr atoms.
36 MATERIALS SCIENCE↗
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↗
Materials Data on OsC4ClO4 by Materials Project
OsCl(CO)4 is Cubic alpha N2-derived structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of eight chloroosmium molecules and thirty-two formaldehyde molecules.
36 MATERIALS SCIENCE↗
Ferrotorryweiserite, Rh 5 Fe 10 S 16 , a New Mineral Species from the Sisim Placer Zone, Eastern Sayans, Russia, and the Torryweiserite–Ferrotorryweiserite Series
Ferrotorryweiserite, Rh 5 Fe 10 S 16 , occurs as small grains (≤20 µm) among droplet-like inclusions (up to 50 μm in diameter) of platinum-group minerals (PGM), in association with oberthürite or Rh-bearing pentlandite, laurite, and a Pt-Pd-Fe alloy (likely isoferroplatinum and Fe-Pd-enriched platinum), hosted by placer grains of Os-Ir alloy (≤0.5 mm) in the River Ko deposit. The latter is a part of the Sisim placer zone, which is likely derived from ultramafic units of the Lysanskiy layered complex, southern Krasnoyarskiy kray, Russia. The mineral is opaque, gray to brownish gray in reflected light, very weakly bireflectant, not pleochroic to weakly pleochroic (grayish to light brown tints), and weakly anisotropic. The calculated density is 5.93 g·cm –3 . Mean results (and ranges) of four WDS analyses are: Ir 18.68 (15.55–21.96), Rh 18.34 (16.32–20.32), Pt 0.64 (0.19–1.14), Ru 0.03 (0.00–0.13), Os 0.07 (0.02–0.17), Fe 14.14 (13.63–14.64), Ni 13.63 (12.58–14.66), Cu 4.97 (3.42–6.41), Co 0.09 (0.07–0.11), S 29.06 (28.48–29.44), and total 99.66 wt.%. They correspond to the following formula calculated for a total of 31 atoms per formula unit: (Rh 3.16 Ir 1.72 Pt 0.06 Ru 0.01 Os 0.01 ) Σ 4.95 (Fe 4.48 Ni 4.11 Cu 1.38 Co 0.03 ) Σ10.00 S 16.05 . The results of synchrotron micro-Laue diffraction studies indicate that ferrotorryweiserite is trigonal; its probable space group is $R\bar{3}m$ (#166) based on its Ni-analog, torryweiserite. The unit-cell parameters refined from 177 reflections are a = 7.069 (2) Å, c = 34.286 (11) Å, V = 1484 (1) Å 3 , and Z = 3. The c:a ratio is 4.8502. The strongest eight peaks in the X-ray diffraction pattern derived from results of micro-Laue diffraction study [d in Å(hkil)(I)] are 2.7950 ($20\bar{2}5$) (100); 5.7143 (0006) (60); 1.7671 ($22\bar{4}0$) (44.4); 3.0486 ($20\bar{2}1$) (39.4); 5.7650 ($10\bar{1}2$) (38.6); 2.5956 ($20\bar{2}7$) (37.8); 3.0058 ($11\bar{2}6$) (36.5); and 1.5029 ($4\bar{2}\bar{2}12$) (35.3). Ferrotorryweiserite and the associated PGM crystallized from microvolumes of residual melt at late stages of crystallization of grains of Os- and Ir-dominant alloys occurred in lode zones of chromitites of the Lysanskiy layered complex. In a particular case, the residual melt is disposed peripherally around a core containing a disequilibrium association of magnesian olivine (Fo 72.9–75.6 ) and albite (Ab 81.6–86.4 ), with the development of skeletal crystals of titaniferous augite: Wo 40.8–43.2 En 26.5–29.3 Fs 20.3–22.6 Aeg 6.9–9.5 (2.82–3.12 wt.% TiO 2 ). Ferrotorryweiserite represents the Fe-dominant analog of torryweiserite. We also report occurrences of ferrotorryweiserite in the Marathon deposit, Coldwell Complex, Ontario, Canada, and infer the existence of the torryweiserite–ferrotorryweiserite solid solution in other deposits and complexes.
58 GEOSCIENCES↗
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↗
Materials Data on OsC3IO3 by Materials Project
IOs(CO)3 crystallizes in the monoclinic P2_1/m space group. The structure is zero-dimensional and consists of twelve formaldehyde molecules and two IOs clusters. In each IOs cluster, Os3+ is bonded in a 2-coordinate geometry to two I1- atoms. There are one shorter (2.78 Å) and one longer (2.80 Å) Os–I bond lengths. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a 6-coordinate geometry to two equivalent Os3+ atoms. In the second I1- site, I1- is bonded in a 4-coordinate geometry to two equivalent Os3+ atoms.
36 MATERIALS SCIENCE↗
Materials Data on La7Os4C9 by Materials Project
La7Os4C9 is Orthorhombic Perovskite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are four inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 7-coordinate geometry to seven C+1.56- atoms. There are a spread of La–C bond distances ranging from 2.69–2.83 Å. In the second La3+ site, La3+ is bonded in a 4-coordinate geometry to four C+1.56- atoms. There are a spread of La–C bond distances ranging from 2.63–2.77 Å. In the third La3+ site, La3+ is bonded in a 5-coordinate geometry to five C+1.56- atoms. There are a spread of La–C bond distances ranging from 2.69–2.78 Å. In the fourth La3+ site, La3+ is bonded in a square co-planar geometry to four C+1.56- atoms. There are two shorter (2.64 Å) and two longer (2.71 Å) La–C bond lengths. There are two inequivalent Os+1.75- sites. In the first Os+1.75- site, Os+1.75- is bonded in a trigonal planar geometry to three C+1.56- atoms. All Os–C bond lengths are 1.93 Å. In the second Os+1.75- site, Os+1.75- is bonded in a 3-coordinate geometry to three C+1.56- atoms. There are a spread of Os–C bond distances ranging from 1.95–2.08 Å. There are five inequivalent C+1.56- sites. In the first C+1.56- site, C+1.56- is bonded to four La3+ and two Os+1.75- atoms to form a mixture of corner and edge-sharing CLa4Os2 octahedra. The corner-sharing octahedra tilt angles range from 18–77°. In the second C+1.56- site, C+1.56- is bonded to five La3+ and one C+1.56- atom to form a mixture of distorted corner and edge-sharing CLa5C octahedra. The corner-sharing octahedra tilt angles range from 0–77°. The C–C bond length is 1.33 Å. In the third C+1.56- site, C+1.56- is bonded to four La3+ and two equivalent Os+1.75- atoms to form a mixture of corner and edge-sharing CLa4Os2 octahedra. The corner-sharing octahedra tilt angles range from 14–35°. In the fourth C+1.56- site, C+1.56- is bonded in a 5-coordinate geometry to three La3+, one Os+1.75-, and one C+1.56- atom. In the fifth C+1.56- site, C+1.56- is bonded to four La3+ and two equivalent Os+1.75- atoms to form a mixture of corner and edge-sharing CLa4Os2 octahedra. The corner-sharing octahedra tilt angles range from 0–35°.
36 MATERIALS SCIENCE↗
Meteoritic material at four Canadian impact craters
Eleven impact melt and six basement rock samples from four craters were analyzed by neutron activation for Au, Co, Cr, Fe, Ge, Ir, Ni, Os, Pd, Re and Se. Wanapitei Lake, Ontario: the impact melts show uniform enrichments corresponding to 1-2% C1-chondrite material. Interelement ratios (Co/Cr, Ni/Cr, Ni/Ir) suggest that the impacting body was a C1-, C2-, or LL-chondrite. Nicholson Lake, North West Territory: Ni, Cr and Co are distinctly more enriched than Ir and Au which tentatively suggests an olivine-rich achondrite (nakhlite or ureilite). Gow Lake, Saskatchewan and Mistastin, Labrador: small enrichments in Ir and Ni; both the low Ir/Ni ratios and low Cr content suggest iron meteorites, but the signals are too weak for conclusive identification. A tentative comparison of meteoritic signatures at 10 large, greater than or equal to 4 km craters and their presumed celestial counterparts (13 Apollo and Amor asteroids) shows more irons and achondrites among known projectile types, and a preponderance of S-type objects, having no known meteoritic equivalent, among asteroids. It is not yet clear that these differences are significant, in view of the tentative nature of the crater identifications and the limited statistics.
Wolf, R.↗
The Activation of Hydrogen by First-Row Transition-Metal Complexes. Final Report
We have assigned the vibrational spectra of Os 1 and Os 2 complexes of propene, butene, and acetylene, and have used them for the assignment of the vibrational frequencies of surface alkenes and alkynes. We have measured the rates of H• transfer from (C 5 R 5 )Cr(CO) 3 H to olefins of many structural types, and have learned that even one substituent on the carbon to which the H• is transferred slows down the reaction considerably. We have shown that these Cr hydrides are useful catalysts for chain transfer during radical polymerization reactions. We have determined the strengths of several M–H bonds (in particular Cr–H ones), and have confirmed that the hydrides of first-row transition metals are particularly useful for generating radicals. We have used H• transfer to terminal methylenes to generate radicals that cyclize. We have shown that (C 5 R 5 )Cr(CO) 3 H can be regenerated under H 2 and is therefore catalytic, but that (P–P)V(CO) 4 H cannot be regenerated from H 2 and therefore can only be used stoichiometrically for radical generation. (The V-H bonds are weaker than the Cr–H ones, and the H• transfer to an olefin is therefore faster.) We have found that, under five atm of H 2 pressure, cobaloximes catalyze H• transfer; they efficiently remove an H• from cyclized radicals, and therefore can be used to catalyze the cycloisomerization of some olefins. We have explored the one- and two-electron oxidation of (Ph 3 P) 6 Cu 6 H 6 . One-electron oxidation (which is reversible) generates a cation radical, whereas two-electron oxidation generates loss of a hydride (i.e., two electrons and a proton). We have found that the hydricity of (Ph 3 P) 6 Cu 6 H 6 is between 36 and 50 kcal/mol. We have shown that uncongested organic radicals (i.e., TEMPO) can catalyze H• transfer from (C 5 R 5 )Cr(CO) 3 H to congested radicals like Ar 3 C•. We have examined the one-electron oxidation of [CpV(CO 3 H] – , and have inferred from the results that the reduction of alkyl iodides with [CpV(CO 3 H] – occurs by one-electron transfer. We have been able to use that reagent to catalyze radical cyclizations from H 2 and appropriate alkyl iodides.
08 HYDROGEN↗
Materials Data on Os5C15SO15 by Materials Project
Os(CO)3Os4C12SO12 is Cubic alpha N2-like structured and crystallizes in the orthorhombic Pna2_1 space group. The structure is zero-dimensional and consists of four Os(CO)3 clusters and four Os4C12SO12 clusters. In each Os(CO)3 cluster, Os2- is bonded in a 3-coordinate geometry to three C+2.80+ atoms. There is two shorter (1.90 Å) and one longer (1.91 Å) Os–C bond length. There are three inequivalent C+2.80+ sites. In the first C+2.80+ site, C+2.80+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.17 Å. In the second C+2.80+ site, C+2.80+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.17 Å. In the third C+2.80+ site, C+2.80+ is bonded in a distorted linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.17 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In each Os4C12SO12 cluster, there are four inequivalent Os2- sites. In the first Os2- site, Os2- is bonded in a 4-coordinate geometry to three C+2.80+ and one S2- atom. There is two shorter (1.89 Å) and one longer (1.92 Å) Os–C bond length. The Os–S bond length is 2.49 Å. In the second Os2- site, Os2- is bonded in a distorted rectangular see-saw-like geometry to three C+2.80+ and one S2- atom. There are a spread of Os–C bond distances ranging from 1.89–1.92 Å. The Os–S bond length is 2.51 Å. In the third Os2- site, Os2- is bonded in a distorted rectangular see-saw-like geometry to three C+2.80+ and one S2- atom. There is two shorter (1.90 Å) and one longer (1.91 Å) Os–C bond length. The Os–S bond length is 2.45 Å. In the fourth Os2- site, Os2- is bonded in a distorted rectangular see-saw-like geometry to three C+2.80+ and one S2- atom. There is two shorter (1.90 Å) and one longer (1.91 Å) Os–C bond length. The Os–S bond length is 2.46 Å. There are twelve inequivalent C+2.80+ sites. In the first C+2.80+ site, C+2.80+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.80+ site, C+2.80+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.17 Å. In the third C+2.80+ site, C+2.80+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.80+ site, C+2.80+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the fifth C+2.80+ site, C+2.80+ is bonded in a distorted linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the sixth C+2.80+ site, C+2.80+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the seventh C+2.80+ site, C+2.80+ is bonded in a distorted linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the eighth C+2.80+ site, C+2.80+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the ninth C+2.80+ site, C+2.80+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the tenth C+2.80+ site, C+2.80+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the eleventh C+2.80+ site, C+2.80+ is bonded in a distorted linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the twelfth C+2.80+ site, C+2.80+ is bonded in a distorted linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. S2- is bonded in a 4-coordinate geometry to four Os2- atoms. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the tenth O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the eleventh O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom. In the twelfth O2- site, O2- is bonded in a single-bond geometry to one C+2.80+ atom.
36 MATERIALS SCIENCE↗
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↗
Materials Data on Os7C19SO19 by Materials Project
(Os(CO)3)3Os4C10SO10 crystallizes in the monoclinic P2_1 space group. The structure is zero-dimensional and consists of six Os(CO)3 clusters and two Os4C10SO10 clusters. In each Os(CO)3 cluster, Os+1.71- is bonded in a 3-coordinate geometry to three C+2.74+ atoms. All Os–C bond lengths are 1.92 Å. There are three inequivalent C+2.74+ sites. In the first C+2.74+ site, C+2.74+ is bonded in a distorted linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.74+ site, C+2.74+ is bonded in a distorted linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.17 Å. In the third C+2.74+ site, C+2.74+ is bonded in a distorted linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.16 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In each Os4C10SO10 cluster, there are four inequivalent Os+1.71- sites. In the first Os+1.71- site, Os+1.71- is bonded in a distorted rectangular see-saw-like geometry to three C+2.74+ and one S2- atom. There is one shorter (1.89 Å) and two longer (1.90 Å) Os–C bond length. The Os–S bond length is 2.48 Å. In the second Os+1.71- site, Os+1.71- is bonded in a 3-coordinate geometry to two C+2.74+ and one S2- atom. There is one shorter (1.89 Å) and one longer (1.90 Å) Os–C bond length. The Os–S bond length is 2.47 Å. In the third Os+1.71- site, Os+1.71- is bonded in a 3-coordinate geometry to two C+2.74+ and one S2- atom. There is one shorter (1.88 Å) and one longer (1.90 Å) Os–C bond length. The Os–S bond length is 2.42 Å. In the fourth Os+1.71- site, Os+1.71- is bonded in a 4-coordinate geometry to three C+2.74+ and one S2- atom. All Os–C bond lengths are 1.90 Å. The Os–S bond length is 2.50 Å. There are ten inequivalent C+2.74+ sites. In the first C+2.74+ site, C+2.74+ is bonded in a distorted linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.17 Å. In the second C+2.74+ site, C+2.74+ is bonded in a distorted linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.74+ site, C+2.74+ is bonded in a distorted linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.17 Å. In the fourth C+2.74+ site, C+2.74+ is bonded in a distorted linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.17 Å. In the fifth C+2.74+ site, C+2.74+ is bonded in a linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.16 Å. In the sixth C+2.74+ site, C+2.74+ is bonded in a distorted linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.17 Å. In the seventh C+2.74+ site, C+2.74+ is bonded in a distorted linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.17 Å. In the eighth C+2.74+ site, C+2.74+ is bonded in a distorted linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.16 Å. In the ninth C+2.74+ site, C+2.74+ is bonded in a distorted linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.17 Å. In the tenth C+2.74+ site, C+2.74+ is bonded in a linear geometry to one Os+1.71- and one O2- atom. The C–O bond length is 1.16 Å. S2- is bonded in a 4-coordinate geometry to four Os+1.71- atoms. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom. In the tenth O2- site, O2- is bonded in a single-bond geometry to one C+2.74+ atom.
36 MATERIALS SCIENCE↗
Investigating Secondary Aerosol Processes in the Amazon through Molecular-level Characterization of Semi-Volatile Organics
In areas where biogenic emissions are oxidized in the presence of anthropogenic pollutants, it has become increasingly apparent that secondary organic aerosol (SOA) formation from biogenic volatile organic compounds (BVOCs) is substantially enhanced. The Amazon forest is the dominant source of BVOCs globally, and the forest is rapidly being converted to urban and agricultural uses. We participated in a collaborative field study located in the Amazon region around Manaus, Brazil, in 2014 (Green Ocean Amazon; GoAmazon). This study was designed to comprehensively examine how BVOC emissions (specifically, the most highly emitted non-methane hydrocarbon, isoprene, and lesser studied sesquiterpenes) and their interaction with anthropogenic pollution (i.e., nitrogen oxides, sulfur dioxide, and black carbon) alter the atmosphere’s oxidative capacity, influence secondary aerosol formation, atmospheric composition and, ultimately, affect the earth’s radiation balance and climate. We provide the first hourly, in-situ measurement of 30 sesquiterpenes and 4 diterpenes, roughly estimating that sesquiterpene oxidation contributes to 10-14% of ozone reactive loss by terpenes and at least 0.4–5% (median 1 %) of total submicron OA mass. However, this is likely a low-end estimate, as evidence for additional unaccounted sesquiterpenes and their oxidation products clearly exists. We also provide new perspectives on sulfate, NO x , and particle acidity influencing isoprene-derived SOA, comparing the central Amazon environment with Southeastern U.S.A. summer, representing clean to polluted conditions, respectively. We find that summed concentrations of isoprene-derived SOA tracers correlated with particulate sulfate spanning three orders of magnitude, suggesting that 1 μg m -3 reduction in sulfate corresponds with at least ~0.5 μg m -3 reduction in isoprene-derived SOA. We also find that SOA mass derived from isoprene oxidation in the presence of NO x is primarily comprised of aerosol sulfate bound with isoprene oxidation products (i.e. organosulfates), ~97% in the Amazon and ~55% in the Southeastern U.S. We infer under natural conditions in high isoprene emission regions, preindustrial aerosol sulfate was almost exclusively isoprene-derived organosulfates, which are traditionally thought as representative of anthropogenic influence. We further report the first field observations showing that particle acidity impacts the distribution of isoprene oxidation tracers in the gas and particle phases, providing physicochemical insight into isoprene SOA formation chemistry. Coupled with other co-located measurements by the DOE Atmospheric Radiation Measurement (ARM) team and collaborating PIs at our measurement site (called T3), on the G1 aircraft, and at additional field sites (T0, T1, T2) this data set has been used to understand emission, oxidation, and particle formation pathways at the molecular level, to elucidate how these pathways change when influenced by anthropogenic sources, and to evaluate their importance for the atmospheric budget of aerosols and the earth’s radiation balance on regional scales. Recommendations: Further constraint of the role of sesquiterpenes on ozone (O 3 ) reactivity and SOA formation is limited by the availability of authentic standards and synthesized compounds of sesquiterpenes and their oxidation products. Future research efforts should focus on making such standards available via custom synthesis to allow for accurate quantification and focused oxidation experiments that will fully elucidate the chemistry of these compounds in the atmosphere. Further, reductions in aerosol sulfate (via SO 2 emissions control) continues to be one of the most effective methods to reduce SOA formation from isoprene, but the concerted role of ammonia (NH 3 ) gas emissions from (agricultural) industry and other sources requires more investigation to better understand the role of aerosol acidity in SOA formation and potential controls. As GoAmazon particles can be more acidic compared to areas with greater anthropogenic NH 3 emissions, this promotes relatively greater organosulfate (OS) formation from isoprene even in the presence of NO x . Because OS and inorganic sulfate differ in water uptake properties, this implies preindustrial aerosol sulfate (albeit less abundant) may have been less reflective than current earth system models assume. Further research should investigate the radiative impacts of organic vs inorganic sulfate in aerosols to improve model representation. Finally, future work (currently underway) should include constraint of the contributions of monoterpene (C 10 H 16 ) BVOCs and biomass burning VOCs as precursors to SOA formation in the region as well as their impacts on radiative forcing in the climate system.
54 ENVIRONMENTAL SCIENCES↗
Materials Data on Os10C23S2O23 by Materials Project
Os(CO)2(OsC3O2)2(Os(CO)3)2Os5C9S2O11 crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of two Os(CO)2 clusters, four Os(CO)3 clusters, two Os5C9S2O11 clusters, and four OsC3O2 clusters. In each Os(CO)2 cluster, Os+1.80- is bonded in an L-shaped geometry to two C+2.96+ atoms. Both Os–C bond lengths are 1.92 Å. There are two inequivalent C+2.96+ sites. In the first C+2.96+ site, C+2.96+ is bonded in a distorted linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.96+ site, C+2.96+ is bonded in a distorted linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.16 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In each Os(CO)3 cluster, Os+1.80- is bonded in a 3-coordinate geometry to three C+2.96+ atoms. There are a spread of Os–C bond distances ranging from 1.89–1.91 Å. There are three inequivalent C+2.96+ sites. In the first C+2.96+ site, C+2.96+ is bonded in a distorted linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.96+ site, C+2.96+ is bonded in a distorted linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.96+ site, C+2.96+ is bonded in a linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.16 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In each Os5C9S2O11 cluster, there are five inequivalent Os+1.80- sites. In the first Os+1.80- site, Os+1.80- is bonded in a 3-coordinate geometry to two C+2.96+ and one S2- atom. There is one shorter (1.90 Å) and one longer (1.91 Å) Os–C bond length. The Os–S bond length is 2.38 Å. In the second Os+1.80- site, Os+1.80- is bonded in a distorted T-shaped geometry to one C+2.96+ and two S2- atoms. The Os–C bond length is 1.91 Å. Both Os–S bond lengths are 2.30 Å. In the third Os+1.80- site, Os+1.80- is bonded in a 3-coordinate geometry to two C+2.96+ and one S2- atom. There is one shorter (1.89 Å) and one longer (1.90 Å) Os–C bond length. The Os–S bond length is 2.46 Å. In the fourth Os+1.80- site, Os+1.80- is bonded in a 3-coordinate geometry to two C+2.96+ and one S2- atom. There is one shorter (1.89 Å) and one longer (1.90 Å) Os–C bond length. The Os–S bond length is 2.46 Å. In the fifth Os+1.80- site, Os+1.80- is bonded in a 3-coordinate geometry to two C+2.96+ and one S2- atom. There is one shorter (1.90 Å) and one longer (1.91 Å) Os–C bond length. The Os–S bond length is 2.38 Å. There are nine inequivalent C+2.96+ sites. In the first C+2.96+ site, C+2.96+ is bonded in a distorted linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.17 Å. In the second C+2.96+ site, C+2.96+ is bonded in a distorted linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.17 Å. In the third C+2.96+ site, C+2.96+ is bonded in a linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.96+ site, C+2.96+ is bonded in a distorted linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.16 Å. In the fifth C+2.96+ site, C+2.96+ is bonded in a distorted linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.17 Å. In the sixth C+2.96+ site, C+2.96+ is bonded in a linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.17 Å. In the seventh C+2.96+ site, C+2.96+ is bonded in a linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.16 Å. In the eighth C+2.96+ site, C+2.96+ is bonded in a distorted linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.17 Å. In the ninth C+2.96+ site, C+2.96+ is bonded in a linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.16 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted single-bond geometry to three Os+1.80- and one O2- atom. The S–O bond length is 1.47 Å. In the second S2- site, S2- is bonded in a distorted single-bond geometry to three Os+1.80- and one O2- atom. The S–O bond length is 1.47 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one S2- atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. The O–C bond length is 1.16 Å. In the tenth O2- site, O2- is bonded in a single-bond geometry to one S2- atom. In each OsC3O2 cluster, Os+1.80- is bonded in a 4-coordinate geometry to three C+2.96+ atoms. There is one shorter (1.76 Å) and two longer (1.93 Å) Os–C bond length. There are three inequivalent C+2.96+ sites. In the first C+2.96+ site, C+2.96+ is bonded in a distorted linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.96+ site, C+2.96+ is bonded in a linear geometry to one Os+1.80- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.96+ site, C+2.96+ is bonded in a single-bond geometry to one Os+1.80- atom. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.96+ atom.
36 MATERIALS SCIENCE↗