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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,045 records · Page 58
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Crystal Growth and Structural Characterization of a Thiocyanato-Bridged Copper(I/II) Mixed-Valence Coordination Polymer

A new mixed-valence coordination polymer [Cu{sub 3}(SCN){sub 4}(DMSO){sub 2}]{sub n} (SCN{sup –} = thiocyanato and DMSO = dimethyl sulfoxide) was prepared and characterized by single crystal X-ray diffraction method. The in situ formation of thiocyanate during the synthesis induces reduction of a part of Cu(II) to Cu(I). The three-dimensional structure of the binuclear thiocyanato bridged compound provided an example of pseudohalide materials containing two different environments for both copper centers.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Synthesis, Crystal Structure, and Luminescent Properties of Ag(I) Coordination Polymer with Tricarboxylic Acid and Flexible N-donor Ligand

The reaction of AgNO{sub 3} with combinations of 1,3-bis(4-pyridyl)propane (bpp) and 1,3,5-benzenetricarboxylic acid (H{sub 3}btc) in aqueous alcohol/ammonia at room temperature produces crystals of {[Ag_6(H_2O)_2(bpp)_6] · (btc)_2 · 25H_2O}{sub n} (Ι). Single crystal X-ray diffraction analysis reveals that the complex Ι consists of 1D infinite cationic chains of [Ag(bpp)]{sub n}{sup n+} and [Ag(H{sub 2}O)(bpp)]{sub n}{sup n+} which are further linked into the cation layer of [Ag(bpp)]{sub n}{sup n+} by Ag···π interactions. The noncoordinated btc{sup 3−} serves as template driving surrounding water molecules to aggregate into the anionic water layer. The neighboring anionic water layer and cationic layer were further alternately joined into a 3D sandwich-like framework by hydrogen bonding. In addition, the luminescent properties of Ι were investigated.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Synthesis, Crystal Structure, and Biological Activity of 1,3,5-Thimethyl-2,4,6-tris(3'-methyl-1'-imidazoliomethylene)Benzene Perchlorate

The title compound, C{sub 24}H{sub 33}C{sub l3}N{sub 6}O{sub 12}(ClO{sub 4}){sub 3}, was synthesized and structurally characterized by elemental analysis, IR, MS, HMR and single crystal X-ray diffraction. The crystals are triclinic, sp. gr. P1, Z = 2. The crystal structure is stabilized by C–H···O hydrogen-bonds forming a three-dimensional network. The preliminary biological test showed that the title compound had anti-Mycobacterium phlei 1180 activity.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Bromination of 1,2,3,4-Tetrahydro-1,10-phenanthroline: Synthesis and Crystal Structure of 6-Bromo-1,2,3,4-tetrahydro-1,10-phenanthroline and Its Bromide Salt

The bromination reaction of 1,2,3,4-tetrahydro-1,10-phenanthroline (tphen) is investigated, which can afford a new heterocyclic compound, namely 6-bromo-1,2,3,4-tetrahydro-1,10-phenanthroline (1). The bromide salt of 1, i.e., 1 · (1H) · Br (2), can be isolated from the bromination system. The accurate structures of both compounds are confirmed and investigated by single-crystal X-ray diffraction. The result proves that the bromination reaction of tphen mainly affords its C6-substituted product. In compounds 1 and 2, the N−H···Br hydrogen bonds play an important role in intermolecular connection. Crystal data of 1: Monoclinic system, sp. gr. Pc, a = 4.6628(8) Å, b = 8.7980(15) Å, c = 13.1347(19) Å, β = 101.342(5)°, Z = 2, V = 528.31(15) Å{sup 3}. Crystal data of 2: Monoclinic system, sp. gr. P2{sub 1}/n, a = 16.6171(16) Å, b = 7.8323(8) Å, c = 18.6972(18) Å, β = 113.597(2)°, Z = 4, V = 2230.0(4) Å{sup 3}.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Synthesis and Crystal Structure of a Four-coordinated Cobalt Complex with 1-Methylbenzimidazole

A four-coordinated complex, L{sub 2}Co(NCO){sub 2}, (L = 1-methylbenzimidazole) has been synthesized and characterized by IR spectroscopy, elemental analyses, and single crystal X-ray diffraction. The crystal is monoclinic, a = 14.522(2) Å, b = 14.610(2) Å, c = 8.6850(13) Å, β = 92.037(3)°, Z = 4, sp. gr. P2{sub 1}/c. Bond lengths Co–N(L) are equal to 2.0165(16) and 2.0174(15) Å, Co–O(NCO) are 1.944(2) and 1.945(2) Å. Intermolecular C–H···O, C–H···N, and C–H···π interactions link the molecules into three-dimensional networks in the crystal.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Crystal and Molecular Structure of 3,5-Diphenyl-4,5-dihydro-2-phenylcarboxamide-1H-pyrazole

Crystal structure of the title compound C{sub 22}H{sub 19}N{sub 3}O is determined by single crystal X-ray diffraction (sp. gr. P2{sub 1}/c, Z = 4). The molecule as a whole, is not planar: phenyl cycles are rotated relative to the plane of pyrazole ring. N−H···N intramolecular hydrogen bond forms five-membered ring fused to pyrazole ring. There are also intramolecular C−H···O and C−H···π interactions. Intermolecular C−H···O hydrogen bond links the molecules into a C(7) chain along the a axis. The crystal structure is stabilized also by C–H···π and π···π intermolecular hydrogen bonds.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2017

Synthesis, Crystal Structure, and Free Radical Scavenging Activity of 4-Aminopyridinium 3,5-Dinitrobenzoate

The crystal structure of 4-aminopyridinium 3,5-dinitrobenzoate, C{sub 12}H{sub 10}O{sub 6}N{sub 4}, has been determined by single-crystal X-ray diffraction technique. The title compound crystallizes in the monoclinic sp. gr. P21/n with the unit cell parameters: a = 7.4726(3) Å, b = 23.0898(9) Å, c = 8.0744(4) Å, V = 1338.64(10) Å{sup 3}, Z = 4. The asymmetric unit of the compound consists of one 3,5-dinitrobenzoate anion and 4-aminopyridine cation. The adjacent anions and cations are linked through two N−H···O hydrogen bonds, N2−H2A···O5 and N{sub 2}−H2B···O6, to form an infinite chain of anions and cations, extended along the [010] direction.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Absolute Configuration of Andrographolide and Its Proliferation of Osteoblast Cell Lines

Andrographolide, C{sub 20}H{sub 30}O{sub 5}, is a labdane diterpenoid which was isolated from the leave of Andrographis paniculata. Its crystal structure is determined by single crystal X-ray diffraction: monoclinic, sp. gr. P2{sub 1}, Z = 2. Absolute configuration is determined by the refinement of the Flack parameter to 0.21(19). In the crystal, molecules are linked by O–H···O hydrogen bonds and C–H···O interactions into two dimensional network parallel to the (001) plane. Its proliferation of osteoblast cell lines is reported.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Synthesis, Structure, and Band Gap of a Novel Inorganic–Organic Hybrid Material Based on Antimony Halide and Organoamine

Using an organoamine, 2,5-bis (1-imidazoly) pyridine (L), a novel inorganic-organic hybrid material based on antimony halide formulated as {(CH_3)_2L}{sup 2+}{(Sb_4Cl_8I_8)"0"."5}{sup 2–}(1) was synthesized in situ via solvothermal technique and characterized by the single-crystal X-ray diffraction. During the synthesis, the organoamine L was transformed in situ into the imidazolium ion, {(CH_3)_2L}{sup 2+}. In the compound 1, four Sb(III) ions are linked by two u{sub 3{sup −}}I{sup –} and four uu{sub 2{sup −}}I{sup –} ligands into a (Sb{sub 4}I{sub 8}Cl{sub 8}){sup 4–}unit, in which eight Cl{sup –}ions and two I{sup –}ions act as the terminal ligands. The uncoordinated {(CH_3)_2L}{sup 2+} organoamine moieties are linked with the (Sb{sub 4}I{sub 8}Cl{sub 8}){sup 4–} clusters via H bonds into three-dimensional (3D) supramolecular architecture. The band structure calculation shows that the compound has an indirect band gap of 2.253 eV.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Molecular and Crystal Structure of 2-{(E)-[(5-Chloro-2-methoxyphenyl)imino]methyl}-4-nitrophenol

The molecular structure of the title compound, C{sub 14}H{sub 11}ClN{sub 2}O{sub 4}, was determined by single crystal X-ray diffraction. The compound crystallizes in the monoclinic sp. gr. P2{sub 1}/c with Z = 4. The title compound, C{sub 14}H{sub 11}ClN{sub 2}O{sub 4}, is a Schiff base which adopts the phenol-imine tautomeric form in the solid state.The molecule is almost planar and the dihedral angle between the planes of two aromatic ring is 2.2(1)°. The molecular structure is stabilized by intramolecular O–H···N hydrogen bond which generates a six-membered ring. In the crystal structure, the molecules are linked together by intermolecular C–H···O interactions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Crystal Structure of 2-((E)-(5-Bromo-2- hydroxybenzylidene)hydrazono)-1,2-diphenylethanone

The molecular structure of the title compound, C{sub 21}H{sub 15}Br{sub 1}N{sub 2}O{sub 2}, was characterized by single crystal X-ray diffraction. The compound crystallizes in the triclinic sp. gr. P1̄ with Z = 2. The molecule is not planar: the dihedral angle between the planes of two aromatic rings [C1/C6] and [C16/C21] is 84.9(2)°. The other dihedral angle between two aromatic rings [C9/C14] and [C16/C21] is 88.8(2)°. The title compound exists as a phenol-imine tautomer, in which a strong intramolecular O–H···N hydrogen bond is formed. This study verifies the preference of the phenol-imine tautomeric form in the solid state. A π–π stacking interactions are also observed, which may influence crystal stability: the distance between centroids is 3.702(2) Å.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Synthesis, Crystal Structure, Antioxidant, and α-Glucosidase Inhibitory Activities of Methoxy-substituted Benzohydrazide Derivatives

Eight methoxy substituted at the benzylidene moiety benzohydrazide derivatives [R = 2-OCH{sub 3} (1), 3-OCH{sub 3} (2), 4-OCH{sub 3} (3), 2,3-(OCH{sub 3}){sub 2} (4), 3,4-(OCH{sub 3}){sub 2} (5), 2,4,5-(OCH{sub 3}){sub 3} (6), 2,4,6-(OCH{sub 3}){sub 3} (7), and 3,4,5-(OCH{sub 3}){sub 3} (8)] were synthesized and characterized by {sup 1}H NMR, FT-IR and UV-Vis spectroscopy. The crystal structure of 4 was determined by single crystal X-ray diffraction (sp. gr. Pbca, Z = 8). The molecule is slightly twisted with the dihedral angle between the two phenyl rings being 9.33(14)°. The methoxy group at the ortho position is twisted [C–O–C–C angle is–109.2(3)°] whereas the other at meta position is co-planar with the attached benzene ring. In the crystal packing, the molecules are linked into two-dimensional network parallel to the (001) plane by O–H···O, O–H···N, and N–H···O hydrogen bonds. Compounds 1–8 were evaluated for an antioxidant and α-glucosidase inhibitory activities and the results suggested that the −OCH{sub 3} substituent was ineffective for bioactivity enhancement.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

A Two-Dimensional Coordination Polymer Based on 1,1':4',1''-Terphenyl-2',4,4'',5'-tetracarboxylate

The coordination polymer, [MnL{sub 0.5}(H{sub 2}O)(phen)]{sub n} (H{sub 4}L = 1,1':4',1''-terphenyl-2',4,4'',5'-tetracarboxylic acid, phen = 1,10-phenanthroline), has been solvothermal synthesized and structurally characterized by single-crystal X-ray diffraction. Complex crystallizes in triclinic sp. gr.P1̄ with Z = 2. Two carboxylate oxygen atoms in the central phenyl rings from two μu{sub 6{sup −}}L{sup 4–} ligands doubly-bridge two Mn(II) ions to form the dinuclear Mn{sub 2}(O{sub COO{sup −}}){sub 2} unit. Each dinuclear Mn{sub 2}(O{sub COO{sup −}}){sub 2} unit links four L{sup 4–} ligands and each L{sup 4–}ligand bridges four dinuclear Mn{sub 2}(O{sub COO{sup −}}){sub 2} units to generate a 2D coordination network, which can be rationalized as a binodal (4,4) topological network by considering the dinuclear Mn{sub 2}(O{sub COO{sup −}}){sub 2} units and L{sup 4–} ligands as 4-connected nodes.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Synthesis, Characterization, Crystal Structure, and Hirshfeld Surface Analysis of Ethyl 2-(4-bromophenyl)-1-cyclohexyl-1H-benzo[d]imidazole-5-carboxylate

The title compound, C{sub 22}H{sub 23}N{sub 2}BrO{sub 2} was synthesized via one-pot reductive cyclization method and characterized by CNH analysis, FT-IR, UV-visible, mass, {sup 1}H and {sup 13}C NMR spectra, thermogravimetric analysis (TGA) and single crystal X-ray diffraction method. The compound crystallizes in monoclinic crystal system: sp. gr. P2{sub 1}/c, Z = 4. The crystal data reveals that the intermolecular interactions of the C–H···π and π···π type connect the molecules which was also visualized with the help of Hirshfeld surface analysis.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Crystal Structure of Liguzinediol, 2,5-Dimethylol-3,6-dimethylpyrazine

The 2,5-dimethylol-3,6-dimethylpyrazine, C{sub 8}H{sub 12}N{sub 2}O{sub 2}, liguzinediol, has been recently discovered as a potential agent for the treatment of heart failure with low safety risk. The crystal structure of liguzinediol, which has been determined by single-crystal X-ray diffraction analysis, is reported for the first time. The liguzinediol crystal may be obtained from 50% ethanol or ethyl acetate. The compound crystallizes in the monoclinic system with the sp. gr. P2{sub 1}/n and the unit cell parameters a = 4.0560(8) Å, b = 12.280(3) Å, c = 8.5370(17) Å, β = 96.93(3)°, Z = 2. The molecule forms S{sub 2}-symmetric conformation in the crystal. The hydroxyl H atom forms short intermolecular contacts with the neighbouring pyrazine N atom, which forms the weak hydrogen bonds in the crystal.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Bacteriochlorin syntheses - Status, problems, and exploration

Bacteriochlorins – Nature’s near-infrared (NIR) chromophores – are distinguished by an intense ([Formula: see text] ∼;10 5 M[Formula: see text]cm[Formula: see text] long-wavelength absorption band in the ∼;700–1000 nm. The development of routes to prepare synthetic, tailorable bacteriochlorins holds promise for multiple disciplines where NIR-light-promoted photoactivity is of interest. A de novo route to bacteriochlorins equipped with a stabilizing gem-dimethyl group in each pyrroline ring was discovered in 2003. Continued development in this arena over 20 years has led to additional routes as well as methods to install substituents at selected positions about the perimeter of the macrocycle. The present paper reports studies that highlight substantial limitations of existing synthetic routes, including stymied access to multi-bacteriochlorin arrays and the inability to install (in a rational way) distinct groups at opposite sides of the macrocycle. The origins of the limitations are traced to particular stages of the chemistry ranging from derivatizing pyrroles, creating pyrrolines, constructing and elaborating dihydrodipyrrins, coupling dihydrodipyrrins, and forming macrocycles. Through exploration of a dozen aspects of bacteriochlorin syntheses, 60 new compounds (and nine known compounds via improved syntheses) have been prepared and characterized; the data include 20 single-crystal X-ray diffraction analyses. The research taken together points to areas of focus to fulfill the promise of this fascinating class of compounds.

Chemistry↗
DOE OSTI2025

Structural features of 11 synthetic bacteriochlorins — comparisons with chlorins and porphyrins

As part of a program to develop the fundamental science of synthetic bacteriochlorins — analogues of Nature’s light-harvesting pigments in anoxygenic photosynthesis — 11 synthetic free base bacteriochlorins have been examined by single-crystal X-ray diffraction analysis. In each bacteriochlorin, each pyrroline ring contains a gem-dimethyl group to block adventitious (aerobic) dehydrogenation. The structural features of the bacteriochlorins (tetrahydroporphyrins) are compared with the less saturated counterparts, chlorins (dihydroporphyrins) and porphyrins. Only slight structural perturbation accrues due to the presence of the gem-dimethyl groups. Furthermore, the results presented herein may aid in understanding metal chelation processes and underpin the development of functional solid-state molecular assemblies.

X-ray diffraction↗
DOE OSTI2016

Transition metals in the transition zone: Crystal chemistry of minor element substitution in wadsleyite

As the most abundant solid phase at depths of 410 to 525 km, wadsleyite constitutes a large geochemical reservoir in the Earth. In order to better understand the implications of minor element substitution and cation ordering in wadsleyite, we have synthesized wadsleyites coexisting with pyroxenes with about 3 wt% of either TiO 2 , Cr 2 O 3 , V 2 O 3 , CoO, NiO, or ZnO under hydrous conditions in separate experiments at 1300 °C and 15 GPa. We have refined the crystal structures of these wadsleyites by single-crystal X-ray diffraction, analyzed the compositions by electron microprobe, and estimated M3 vacancy concentration from b/a cell-parameter ratios. According to the crystal structure refinements, trivalent cations Fe 3+ , Cr 3+ and V 3+ , show a strong preference for M3 over M1 and M2 and significant substitution up to 2.7 % (atomic percent) at the tetrahedral site (T site). Divalent cations, Ni 2+ , Co 2+ , and Zn 2+ show site preferences similar to those of Fe2+ with M1≈ M3 > M2 > T. Transition metal site preferences appear to correlate with crystal field stabilization energies (CFSE) and are inconsistent with cation radius effects. The avoidance of Ni 2+ , Co 2+ and Fe 2+ for the M2 site in both wadsleyite and olivine can be influenced by CFSE, which has a positive correlation with site preferences at octahedral sites, indicating that avoidance of the lower-symmetry M2 site is stronger for cations having lower (greater absolute value) CFSE. Ti 4+ substitutes primarily into the M3 octahedron, rather than M1, M2, or T sites. Electron microprobe analysis reveals that Ti 4+ , Cr 3+ , and V 3+ have greater solubility in wadsleyite than in olivine. Furthermore these transition metal cations may be enriched in a melt or an accessory phase if hydrous melting occurs on upward convection across the wadsleyite-olivine boundary and may be useful as indicators of high pressure origin.

36 MATERIALS SCIENCE↗