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DOE OSTI2026

Binuclear Acetoniminato Derivatives of Iron and Chromium Carbonyls: A Theoretical Study

The structures and energetics of binuclear acetoniminato metal carbonyl derivatives of the types (Me 2 C═N) 2 Fe 2 (CO) n and (Me 2 C═N) 2 Cr 2 (CO) n have been investigated by density functional theory. The (Me 2 C═N) 2 Fe 2 (CO) 6 structure, with bridging Me 2 C═N ligands using only their nitrogen atoms to bridge an Fe═Fe bond related to experimentally known species, as well as a related (Me 2 C═N) 2 Cr 2 (CO) 8 structure, appear to be energetically preferred. Among carbonyl-richer systems, the iron system energetically prefers a {Me 2 C═NC(O)} 2 Fe 2 (CO) 6 structure with bridging Me 2 C═NC(O) ligands, whereas the chromium system energetically prefers a structure with a 2,3-diazabutadiene ligand having each nitrogen atom bonded to a Cr(CO) 5 moiety. Preferred structures for systems with fewer CO groups include the tetracarbonyl (Me 2 C═N) 2 Fe 2 (CO) 4 in which one of the bridging Me 2 C═N uses its C═N double bond to bond to an iron atom, as well as (Me 2 C═N)2Cr 2 (CO) n (n = 7, 6) structures with chromium–chromium multiple bonds bridged by Me2C═N groups.

Carbonyls↗

DOE OSTI2020

Materials Data on Li2(BH)7 by Materials Project

(Li(BH)3)2BH crystallizes in the monoclinic C2 space group. The structure is one-dimensional and consists of two boranediylradical molecules and two Li(BH)3 ribbons oriented in the (1, 0, 0) direction. In each Li(BH)3 ribbon, there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 2-coordinate geometry to four H1+ atoms. There are two shorter (2.00 Å) and two longer (2.29 Å) Li–H bond lengths. In the second Li1+ site, Li1+ is bonded in a 2-coordinate geometry to four H1+ atoms. There are two shorter (2.21 Å) and two longer (2.26 Å) Li–H bond lengths. There are three inequivalent B+1.29- sites. In the first B+1.29- site, B+1.29- is bonded in a distorted single-bond geometry to one H1+ atom. The B–H bond length is 1.21 Å. In the second B+1.29- site, B+1.29- is bonded in a single-bond geometry to one H1+ atom. The B–H bond length is 1.21 Å. In the third B+1.29- site, B+1.29- is bonded in a distorted single-bond geometry to one H1+ atom. The B–H bond length is 1.21 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted L-shaped geometry to one Li1+ and one B+1.29- atom. In the second H1+ site, H1+ is bonded in a 3-coordinate geometry to two Li1+ and one B+1.29- atom. In the third H1+ site, H1+ is bonded in a water-like geometry to one Li1+ and one B+1.29- atom.

36 MATERIALS SCIENCE↗

DOE OSTI2021

Chemical Preparation, Crystal Structure Reinvestigation and Vibrational Study of CoNa 3 P 3 O 10 ·12H 2 O and X-ray Characterization of the New Anhydrous Triphosphate CoNa 3 P 3 O 10

The triphosphate dodecahydrate of cobalt and sodium CoNa 3 P 3 O 10 ·12H 2 O was prepared by the ion exchange resin process. Its structure was studied by X-ray diffraction and determined in the monoclinic space group P12 1 /c1 with the unit-cell parameters a = 14.6650(5) Å, b=9.1916(3) Å, c = 15.0239(5) Å,β =90.2210(10)°, Z = 4 and V = 2025.13(12) Å 3 . The thermal dehydration of this compound was performed, leading to an anhydrous new form, CoNa 3 P 3 O 10 , which was characterized by X-ray diffraction. The obtained CoNa 3 P 3 O 10 crystallized in monoclinic space group P21/n with the unit-cell parameters a=15,3774 Å, b=7,6988 A°, c=14,2832A°, β=92,9115°. The characteristic IR wavenumbers of the P 3 O 10 5- ions observed in the vibrational spectra were calculated using isotopic substitutions, which confirms the existence of these groups in the studied compound. A comparison between the IR and Raman wavenumbers of CoNa 3 P 3 O 10 ·12H 2 O, CoNa 3 P 3 O 10 and Na 5 P 3 O 10 ·12H 2 was performed. A kinetic study was also made for CoNa 3 P 3 O 10 ·12H 2 O.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

NASA NTRS2000

Pulmonary Toxicity Study of Lunar and Martian Dust Simulants Intratracheally Instilled in Mice

NASA is contemplating sending humans to Mars and the Moon for further exploration. The properties of Hawaiian and Californian volcanic ashes allow them to be used to simulate Martian and lunar dusts, respectively. NASA laboratories use these dust simulants to test performance of hardware destined for Martian or lunar environments. Workers in these test facilities are exposed to low levels of these dusts. The present study was conducted to investigate the toxicity of these dust simulants. Particles of respirable-size ranges of lunar simulant (LS), Martian simulant (MS), TiO2 (negative control) and quartz (positive control) were each intratracheally instilled (saline as vehicle) to groups of 4 mice (C57BL, male, 2-3 month old) at a single treatment of 1 (Hi dose) or 0.1 (Lo dose) mg/mouse. The lungs were harvested at the end of 7 days or 90 days for histopathological examination. Lungs of the LS-Lo groups had no evidence of inflammation, edema or fibrosis. The LS-Hi-7d group had mild to moderate acute inflammation, and neutrophilic and lymphocytic infiltration; the LS-Hi-90d group showed signs of chronic inflammation and some fibrosis. Lungs of the MS-Lo-7d group revealed mild inflammation and neutrophilic and lymphocytic infiltration; the MS-Lo-90d group showed mild fibrosis and particle-laden macrophages (PLM). Lungs of the MS-Hi-7d group demonstrated mild to moderate inflammation and large foci of PLM; the MS-Hi-90d group showed chronic mild to moderate inflammation and fibrosis. To mimic the effects of the oxidative and reactive properties of Martian soil surface, groups of mice were exposed to ozone (3 hour at 0.5 ppm) prior to MS dust instillation. Lung lesions in the MS group were more severe with the pretreatment. The results for the negative and positive controls were consistent with the known pulmonary toxicity of these compounds. The overall severity of toxic insults to the lungs were TiO2<LS<MS<Quartz. For the mice in the 90-d study, blood samples were taken for immunotoxicity study. Antinuclear antibodies (such as those against Golgi, kinetichore, and centromere) were detected in serum in a greater extent in mice treated with LS than those with quartz, suggesting that LS, like quartz, has the potential of inducing antoimmune disease.

Lam, Chiu-Wing↗

DOE OSTI2022

Thermally stable hydrocarbon-based anion exchange membrane and ionomers

An anion exchange membrane is composed of a copolymer of 1,1-diphenylethylene and one or more styrene monomers, such as 4-tert-butylstyrene. The copolymer includes a backbone substituted with a plurality of ionic groups coupled to phenyl groups on the backbone via hydrocarbyl tethers between about 1 and about 7 carbons in length. High-temperature conditions enabled by these copolymers enhance conductivity performance, making them particularly suitable for use in anion exchange membranes in fuel cells, electrolyzers employing hydrogen, ion separations, etc. The properties of the membranes can be tuned via the degree of functionalization of the phenyl groups and selection of the functional groups, such as quaternary ammonium groups. Several processes can be used to incorporate the desired ionic functional groups into the polymers, such as chloromethylation, radical bromination, Friedel-Crafts acylation and alkylation, sulfonation followed by amination, or combinations thereof.

Lee, Sangwoo↗

DOE OSTI2024

Thermally stable hydrocarbon-based anion exchange membrane and ionomers

Lee, Sangwoo↗

DOE OSTI2020

Materials Data on CoH16C4(NO)7 by Materials Project

CoC4H16(N3O2)2NO3 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four nitric acid molecules and four CoC4H16(N3O2)2 clusters. In each CoC4H16(N3O2)2 cluster, Co3+ is bonded in an octahedral geometry to six N3- atoms. There are a spread of Co–N bond distances ranging from 1.94–1.97 Å. There are four inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal non-coplanar geometry to one N3- and two H1+ atoms. The C–N bond length is 1.49 Å. Both C–H bond lengths are 1.10 Å. In the second C4+ site, C4+ is bonded in a trigonal non-coplanar geometry to one N3- and two H1+ atoms. The C–N bond length is 1.49 Å. Both C–H bond lengths are 1.10 Å. In the third C4+ site, C4+ is bonded in a trigonal non-coplanar geometry to one N3- and two H1+ atoms. The C–N bond length is 1.48 Å. Both C–H bond lengths are 1.10 Å. In the fourth C4+ site, C4+ is bonded in a trigonal non-coplanar geometry to one N3- and two H1+ atoms. The C–N bond length is 1.49 Å. Both C–H bond lengths are 1.10 Å. There are six inequivalent N3- sites. In the first N3- site, N3- is bonded in a trigonal planar geometry to one Co3+ and two O2- atoms. There is one shorter (1.25 Å) and one longer (1.26 Å) N–O bond length. In the second N3- site, N3- is bonded in a trigonal planar geometry to one Co3+ and two O2- atoms. Both N–O bond lengths are 1.25 Å. In the third N3- site, N3- is bonded to one Co3+, one C4+, and two H1+ atoms to form distorted corner-sharing NCoH2C tetrahedra. Both N–H bond lengths are 1.03 Å. In the fourth N3- site, N3- is bonded to one Co3+, one C4+, and two H1+ atoms to form distorted corner-sharing NCoH2C tetrahedra. Both N–H bond lengths are 1.03 Å. In the fifth N3- site, N3- is bonded to one Co3+, one C4+, and two H1+ atoms to form distorted corner-sharing NCoH2C tetrahedra. Both N–H bond lengths are 1.03 Å. In the sixth N3- site, N3- is bonded to one Co3+, one C4+, and two H1+ atoms to form distorted corner-sharing NCoH2C tetrahedra. Both N–H bond lengths are 1.03 Å. There are sixteen inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. In the thirteenth H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. In the fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one C4+ atom. In the fifteenth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the sixteenth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N3- atom. In the second O2- site, O2- is bonded in a single-bond geometry to one N3- atom. In the third O2- site, O2- is bonded in a single-bond geometry to one N3- atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one N3- atom.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on P6H17S6(NO)7 by Materials Project

P6N7H9S6O3(H2O)4 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of eight water molecules and one P6N7H9S6O3 cluster. In the P6N7H9S6O3 cluster, there are six inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to three N3- and one S2- atom to form corner-sharing PSN3 tetrahedra. There is one shorter (1.66 Å) and two longer (1.71 Å) P–N bond length. The P–S bond length is 1.92 Å. In the second P5+ site, P5+ is bonded to three N3- and one S2- atom to form distorted corner-sharing PSN3 tetrahedra. There are a spread of P–N bond distances ranging from 1.66–1.73 Å. The P–S bond length is 1.91 Å. In the third P5+ site, P5+ is bonded to three N3- and one S2- atom to form distorted corner-sharing PSN3 tetrahedra. There is one shorter (1.67 Å) and two longer (1.72 Å) P–N bond length. The P–S bond length is 1.92 Å. In the fourth P5+ site, P5+ is bonded to three N3- and one S2- atom to form distorted corner-sharing PSN3 tetrahedra. There are a spread of P–N bond distances ranging from 1.66–1.73 Å. The P–S bond length is 1.92 Å. In the fifth P5+ site, P5+ is bonded to three N3- and one S2- atom to form distorted corner-sharing PSN3 tetrahedra. There are a spread of P–N bond distances ranging from 1.67–1.73 Å. The P–S bond length is 1.91 Å. In the sixth P5+ site, P5+ is bonded to three N3- and one S2- atom to form distorted corner-sharing PSN3 tetrahedra. There are a spread of P–N bond distances ranging from 1.67–1.74 Å. The P–S bond length is 1.91 Å. There are seven inequivalent N3- sites. In the first N3- site, N3- is bonded in a trigonal planar geometry to three P5+ atoms. In the second N3- site, N3- is bonded in a trigonal planar geometry to two P5+ and one H1+ atom. The N–H bond length is 1.11 Å. In the third N3- site, N3- is bonded in a trigonal planar geometry to three P5+ atoms. In the fourth N3- site, N3- is bonded in a trigonal planar geometry to two P5+ and one H1+ atom. The N–H bond length is 1.08 Å. In the fifth N3- site, N3- is bonded in a trigonal planar geometry to two P5+ and one H1+ atom. The N–H bond length is 1.13 Å. In the sixth N3- site, N3- is bonded in a trigonal planar geometry to three P5+ atoms. In the seventh N3- site, N3- is bonded in a trigonal planar geometry to three P5+ atoms. There are nine inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a linear geometry to one N3- and one O2- atom. The H–O bond length is 1.49 Å. In the second H1+ site, H1+ is bonded in a linear geometry to one N3- and one O2- atom. The H–O bond length is 1.58 Å. In the third H1+ site, H1+ is bonded in a linear geometry to one N3- and one O2- atom. The H–O bond length is 1.43 Å. In the fourth 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 fifth 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 sixth 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 seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the eighth 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 ninth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a single-bond geometry to one P5+ atom. In the second S2- site, S2- is bonded in a single-bond geometry to one P5+ atom. In the third S2- site, S2- is bonded in a single-bond geometry to one P5+ atom. In the fourth S2- site, S2- is bonded in a single-bond geometry to one P5+ atom. In the fifth S2- site, S2- is bonded in a single-bond geometry to one P5+ atom. In the sixth S2- site, S2- is bonded in a single-bond geometry to one P5+ atom. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to three H1+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three H1+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three H1+ atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Ag3(Bi2Br3)7 by Materials Project

(AgBi4Br7)3(Bi)2 crystallizes in the monoclinic Pm space group. The structure is three-dimensional and consists of four bismuth molecules and one AgBi4Br7 framework. In the AgBi4Br7 framework, there are three inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to six Br1- atoms to form distorted AgBr6 octahedra that share a cornercorner with one AgBr6 octahedra, an edgeedge with one AgBr6 octahedra, and edges with three BiBr6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of Ag–Br bond distances ranging from 2.68–3.18 Å. In the second Ag1+ site, Ag1+ is bonded to six Br1- atoms to form distorted AgBr6 octahedra that share a cornercorner with one AgBr6 octahedra, edges with two AgBr6 octahedra, and edges with two BiBr6 octahedra. The corner-sharing octahedral tilt angles are 63°. There are a spread of Ag–Br bond distances ranging from 2.67–3.33 Å. In the third Ag1+ site, Ag1+ is bonded to six Br1- atoms to form distorted AgBr6 octahedra that share a cornercorner with one AgBr6 octahedra, an edgeedge with one AgBr6 octahedra, and edges with three BiBr6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of Ag–Br bond distances ranging from 2.74–3.12 Å. There are fifteen inequivalent Bi+1.29+ sites. In the first Bi+1.29+ site, Bi+1.29+ is bonded in a 3-coordinate geometry to three Br1- atoms. There are two shorter (3.55 Å) and one longer (3.59 Å) Bi–Br bond lengths. In the second Bi+1.29+ site, Bi+1.29+ is bonded to six Br1- atoms to form BiBr6 octahedra that share a cornercorner with one BiBr6 octahedra, edges with two AgBr6 octahedra, and edges with two BiBr6 octahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of Bi–Br bond distances ranging from 2.78–3.01 Å. In the third Bi+1.29+ site, Bi+1.29+ is bonded in a 3-coordinate geometry to three Br1- atoms. There are a spread of Bi–Br bond distances ranging from 3.43–3.57 Å. In the fourth Bi+1.29+ site, Bi+1.29+ is bonded in a 3-coordinate geometry to three Br1- atoms. There are two shorter (3.32 Å) and one longer (3.52 Å) Bi–Br bond lengths. In the fifth Bi+1.29+ site, Bi+1.29+ is bonded to six Br1- atoms to form BiBr6 octahedra that share a cornercorner with one BiBr6 octahedra, an edgeedge with one BiBr6 octahedra, and edges with three AgBr6 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Bi–Br bond distances ranging from 2.81–3.05 Å. In the sixth Bi+1.29+ site, Bi+1.29+ is bonded in a 3-coordinate geometry to three Br1- atoms. There are a spread of Bi–Br bond distances ranging from 3.33–3.53 Å. In the seventh Bi+1.29+ site, Bi+1.29+ is bonded in a square co-planar geometry to four Br1- atoms. There are two shorter (2.88 Å) and two longer (2.91 Å) Bi–Br bond lengths. In the eighth Bi+1.29+ site, Bi+1.29+ is bonded in an L-shaped geometry to two Br1- atoms. There are one shorter (3.02 Å) and one longer (3.35 Å) Bi–Br bond lengths. In the ninth Bi+1.29+ site, Bi+1.29+ is bonded in a single-bond geometry to one Br1- atom. The Bi–Br bond length is 3.31 Å. In the tenth Bi+1.29+ site, Bi+1.29+ is bonded in a rectangular see-saw-like geometry to four Br1- atoms. There are two shorter (2.95 Å) and two longer (2.99 Å) Bi–Br bond lengths. In the eleventh Bi+1.29+ site, Bi+1.29+ is bonded in a 2-coordinate geometry to two Br1- atoms. There are one shorter (3.04 Å) and one longer (3.40 Å) Bi–Br bond lengths. In the twelfth Bi+1.29+ site, Bi+1.29+ is bonded to six Br1- atoms to form BiBr6 octahedra that share a cornercorner with one BiBr6 octahedra, an edgeedge with one BiBr6 octahedra, and edges with three AgBr6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of Bi–Br bond distances ranging from 2.76–3.16 Å. In the thirteenth Bi+1.29+ site, Bi+1.29+ is bonded in a 1-coordinate geometry to four Br1- atoms. There are a spread of Bi–Br bond distances ranging from 3.25–3.57 Å. In the fourteenth Bi+1.29+ site, Bi+1.29+ is bonded in a 5-coordinate geometry to five Br1- atoms. There are a spread of Bi–Br bond distances ranging from 2.89–3.26 Å. In the fifteenth Bi+1.29+ site, Bi+1.29+ is bonded in a 3-coordinate geometry to three Br1- atoms. There are one shorter (3.43 Å) and two longer (3.50 Å) Bi–Br bond lengths. There are twenty-six inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in an L-shaped geometry to two Bi+1.29+ atoms. In the second Br1- site, Br1- is bonded in a 10-coordinate geometry to two equivalent Bi+1.29+ atoms. In the third Br1- site, Br1- is bonded in a 3-coordinate geometry to one Ag1+ and two Bi+1.29+ atoms. In the fourth Br1- site, Br1- is bonded in a 2-coordinate geometry to four Bi+1.29+ atoms. In the fifth Br1- site, Br1- is bonded in a 2-coordinate geometry to two equivalent Bi+1.29+ atoms. In the sixth Br1- site, Br1- is bonded in a bent 120 degrees geometry to two equivalent Bi+1.29+ atoms. In the seventh Br1- site, Br1- is bonded in a distorted T-shaped geometry to one Ag1+ and two Bi+1.29+ atoms. In the eighth Br1- site, Br1- is bonded in a 1-coordinate geometry to four Bi+1.29+ atoms. In the ninth Br1- site, Br1- is bonded in a distorted L-shaped geometry to one Ag1+ and two Bi+1.29+ atoms. In the tenth Br1- site, Br1- is bonded in a distorted L-shaped geometry to one Ag1+ and two Bi+1.29+ atoms. In the eleventh Br1- site, Br1- is bonded in a bent 120 degrees geometry to two equivalent Ag1+ atoms. In the twelfth Br1- site, Br1- is bonded in a distorted trigonal non-coplanar geometry to two Ag1+ and one Bi+1.29+ atom. In the thirteenth Br1- site, Br1- is bonded in a 3-coordinate geometry to three Bi+1.29+ atoms. In the fourteenth Br1- site, Br1- is bonded in a 4-coordinate geometry to four Bi+1.29+ atoms. In the fifteenth Br1- site, Br1- is bonded in a 3-coordinate geometry to two Ag1+ and one Bi+1.29+ atom. In the sixteenth Br1- site, Br1- is bonded in a bent 120 degrees geometry to two equivalent Ag1+ and one Bi+1.29+ atom. In the seventeenth Br1- site, Br1- is bonded in an L-shaped geometry to one Ag1+ and one Bi+1.29+ atom. In the eighteenth Br1- site, Br1- is bonded in a distorted T-shaped geometry to two Ag1+ and one Bi+1.29+ atom. In the nineteenth Br1- site, Br1- is bonded in a 3-coordinate geometry to four Bi+1.29+ atoms. In the twentieth Br1- site, Br1- is bonded in a distorted trigonal non-coplanar geometry to two Ag1+ and one Bi+1.29+ atom. In the twenty-first Br1- site, Br1- is bonded in a bent 120 degrees geometry to two equivalent Bi+1.29+ atoms. In the twenty-second Br1- site, Br1- is bonded in an L-shaped geometry to two equivalent Bi+1.29+ atoms. In the twenty-third Br1- site, Br1- is bonded in a 4-coordinate geometry to two equivalent Ag1+ and two Bi+1.29+ atoms. In the twenty-fourth Br1- site, Br1- is bonded in a 3-coordinate geometry to one Ag1+ and two Bi+1.29+ atoms. In the twenty-fifth Br1- site, Br1- is bonded in a 2-coordinate geometry to four Bi+1.29+ atoms. In the twenty-sixth Br1- site, Br1- is bonded in a distorted T-shaped geometry to one Ag1+ and two Bi+1.29+ atoms.

36 MATERIALS SCIENCE↗

NASA NTRS1997

Effects of 14 days of spaceflight and nine days of recovery on cell body size and succinate dehydrogenase activity of rat dorsal root ganglion neurons

The cross-sectional areas and succinate dehydrogenase activities of L5 dorsal root ganglion neurons in rats were determined after 14 days of spaceflight and after nine days of recovery. The mean and distribution of the cross-sectional areas were similar to age-matched, ground-based controls for both the spaceflight and for the spaceflight plus recovery groups. The mean succinate dehydrogenase activity was significantly lower in spaceflight compared to aged-matched control rats, whereas the mean succinate dehydrogenase activity was similar in age-matched control and spaceflight plus recovery rats. The mean succinate dehydrogenase activity of neurons with cross-sectional areas between 1000 and 2000 microns2 was lower (between 7 and 10%) in both the spaceflight and the spaceflight plus recovery groups compared to the appropriate control groups. The reduction in the oxidative capacity of a subpopulation of sensory neurons having relatively large cross-sectional areas immediately following spaceflight and the sustained depression for nine days after returning to 1 g suggest that the 0 g environment induced significant alterations in proprioceptive function.

manned↗

DOE OSTI2020

High-pressure synthesis, crystal structure, and magnetic properties of the Shastry-Sutherland-lattice oxides BaL n 2 ZnO 5 (L n = Pr, Sm, Eu)

BaPr 2 ZnO 5 , BaSm 2 ZnO 5 , and BaEu 2 ZnO 5 – a series of 4f magnetic insulators comprising the Shastry-Sutherland lattice – were synthesized via a solid-state reaction under high-pressure and high-temperature conditions. The magnetic behaviors are well characterized by the localized 4f electrons of each Ln 3+ (= Pr, Sm, Eu) under the influence of the crystal-electric field of the surrounding ions. The magnetic susceptibility and heat capacity measurements of BaPr 2 ZnO 5 (Pr 3+ ; 4f 2 3 H 4 ) indicate the splitting of the ground state J-multiplet due to the crystal-electric field. BaSm 2 ZnO 5 (Sm 3+ ; 4f 5 6 H 5/2 ) is a strong Van Vleck paramagnet, while BaEu 2 ZnO 5 is non-magnetic due to the 7 F 0 ground state (Eu 3+ ; 4f 6 7 F 0 ). The series of new oxides enriches a group of the Shastry-Sutherland lattice materials and helps to develop a range of two-dimensional quantum materials.

36 MATERIALS SCIENCE↗

DOE OSTI2024

Development of Half-Sandwich Ru, Os, Rh, and Ir Complexes Bearing the Pyridine-2-ylmethanimine Bidentate Ligand Derived from 7-Chloroquinazolin-4(3H)-one with Enhanced Antiproliferative Activity

Kinesin spindle protein (KSP) inhibitors are one of the most promising anticancer agents developed in recent years. Herein, we report the synthesis of ispinesib-core pyridine derivative conjugates, which are potent KSP inhibitors, with half-sandwich complexes of ruthenium, osmium, rhodium, and iridium. Conjugation of 7-chloroquinazolin-4(3H)-one with the pyridine-2-ylmethylimine group and the organometallic moiety resulted in up to a 36-fold increased cytotoxicity with IC 50 values in the micromolar and nanomolar range also toward drug-resistant cells. All studied conjugates increased the percentage of cells in the G 2 /M phase, simultaneously decreasing the number of cells in the G 1 /G 0 phase, suggesting mitotic arrest. Additionally, ruthenium derivatives were able to generate reactive oxygen species (ROS); however, no significant influence of the organometallic moiety on KSP inhibition was observed, which suggests that conjugation of a KSP inhibitor with the organometallic moiety modulates its mechanism of action.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2020

Purely Cubic Spin Splittings with Persistent Spin Textures

Purely cubic spin splittings in the band structure of bulk insulators have not been extensively investigated yet despite the fact that they may pave the way for novel spin-orbitronic applications and can also result in a variety of promising spin phenomena. By symmetry analysis and first-principles simulations, we report symmetry-enforced purely cubic spin splittings (SEPCSS) that can even lead to persistent spin textures. In particular, these SEPCSS can be thought to be complementary to the cubic Rashba and cubic Dresselhaus types of spin splittings. Strikingly, the presently discovered SEPCSS are expected to exist in the large family of materials crystallizing in the $\bar{6}m2$ and $\bar{6}$ point groups, including the Ge 3 Pb 5 O 11 , Pb 7 Br 2 F 12 , and Pb 7 Cl 2 F 12 compounds.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Effect of gap size on composition and structure of regeneration 19 years after harvest in a southeastern bottomland forest, USA

Following timber harvests in bottomland mixed-oak (Quercus L.) stands, desirable oak advance regeneration can be overgrown by shade-intolerant pioneer species. We investigated the effects of group selection opening size on composition of tree regeneration 19 years postharvest in an oak-dominated bottomland forest and compared results with earlier findings to evaluate development trends. In response to six opening sizes (7–40 m radii), we evaluated regeneration density and dominance of four tree species groups: conifers, hard mast, shade-intolerant hardwoods, and shade-tolerant hardwoods. Our objectives were to determine the optimum gap size for regenerating oaks and test the delayed oak dominance hypothesis, in which oaks slowly gain dominance as pioneer species undergo self-thinning. Opening size influenced conifer regeneration but minimally affected hardwoods. Hard mast species density was less than that of either intolerant or tolerant species regardless of opening size. Future stem density trends suggest increasing intolerant species and constant mast and tolerant species. Modeled future height trends suggest increasing mast species dominance over intolerant pioneers after 30 years. Furthermore, our results suggest that gap-based silviculture can be used to regenerate bottomland hardwood stands with desirable species including oaks; larger gaps favor conifers but there was no optimum size to enhance oak regeneration.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2020

Materials Data on Bi2Te4Cl7 by Materials Project

Bi4TeCl14(Te)7 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is two-dimensional and consists of twenty-eight tellurium molecules and two Bi4TeCl14 sheets oriented in the (0, 0, 1) direction. In each Bi4TeCl14 sheet, there are four inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six Cl1- atoms. There are a spread of Bi–Cl bond distances ranging from 2.55–3.11 Å. In the second Bi3+ site, Bi3+ is bonded in a 8-coordinate geometry to eight Cl1- atoms. There are a spread of Bi–Cl bond distances ranging from 2.55–3.41 Å. In the third Bi3+ site, Bi3+ is bonded in a 6-coordinate geometry to six Cl1- atoms. There are a spread of Bi–Cl bond distances ranging from 2.57–3.23 Å. In the fourth Bi3+ site, Bi3+ is bonded in a 5-coordinate geometry to five Cl1- atoms. There are a spread of Bi–Cl bond distances ranging from 2.52–3.16 Å. Te+0.25+ is bonded in a single-bond geometry to one Cl1- atom. The Te–Cl bond length is 3.31 Å. There are fourteen inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Bi3+ atom. In the second Cl1- site, Cl1- is bonded in a trigonal non-coplanar geometry to three Bi3+ atoms. In the third Cl1- site, Cl1- is bonded in a distorted bent 120 degrees geometry to two Bi3+ atoms. In the fourth Cl1- site, Cl1- is bonded in a distorted trigonal non-coplanar geometry to three Bi3+ atoms. In the fifth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Bi3+ atoms. In the sixth Cl1- site, Cl1- is bonded in a single-bond geometry to one Bi3+ atom. In the seventh Cl1- site, Cl1- is bonded in a single-bond geometry to one Bi3+ atom. In the eighth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Bi3+ atoms. In the ninth Cl1- site, Cl1- is bonded in a single-bond geometry to one Bi3+ atom. In the tenth Cl1- site, Cl1- is bonded in a distorted water-like geometry to two Bi3+ and one Te+0.25+ atom. In the eleventh Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Bi3+ atoms. In the twelfth Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Bi3+ atoms. In the thirteenth Cl1- site, Cl1- is bonded in a single-bond geometry to one Bi3+ atom. In the fourteenth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to two Bi3+ atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on H34C19 by Materials Project

(CH3)3(CH2)7(CH)4C5H7 crystallizes in the monoclinic P2_1 space group. The structure is zero-dimensional and consists of eight methane molecules, fourteen methane molecules, six methane molecules, and two neopentane molecules.

36 MATERIALS SCIENCE↗

NASA NTRS1982

Diffraction studies of the high pressure phases of GaAs and GaP

High pressure structural phase transitions of GaAs and GaP have been studied by energy dispersive X-ray diffraction with the radiation from the Cornell High Energy Synchrotron Source. GaAs began to transform at 172 + or - 7 kbar to an orthorhombic structure possibly belonging to space group Fmmm. GaP transformed to a tetragonal beta-Sn type phase at 215 + or - 8 kbar. Although pressure transmitting media were used to minimize shear stresses in the specimens, the high pressure diffraction results were interpreted as showing evidence for planar defects in the specimens.

Baublitz, M., Jr.↗

NASA NTRS1992

The carbon isotope biogeochemistry of acetate from a methanogenic marine sediment

The delta C-13 value of porewater acetate isolated from the anoxic sediments of Cape Lookout Bight (North Carolina) ranged from -17.6 percent in the sulfate reduction zone to -2.8 percent in the underlying methanogenic zone. The large C-13 enrichment in the sulfate-depleted sediments appears to be associated with the dissimilation of acetate to CH4 and CO2. Fractionation factors for that process were estimated to be 1.032 +/- 0.014 and 1.036 +/- 0.019 for the methyl and carboxyl groups. A subsurface maximum in delta C-13 of the total acetate molecule, as well as the methyl and carboxyl carbons at 10-15 cm depth within the sediment column, indicate that changes in the relative rates of acetate cycling pathways occur in the methanogenic zone. The methyl group of the acetate was depleted in C-13 by 7-14 percent relative to the carboxyl moiety. The intramolecular heterogeneity may be the result of both synthetic and catabolic isotope effects.

Blair, N. E.↗