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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 1,567 records · Page 87
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Synthesis and Molecular Structure of 2-(4-Chlorophenyl)-3-(phenyl-amino)-5-(thiophen-2-ylmethylidene)-3,5-dihydro-4H-imidazol-4-one

2-(4-Chlorophenyl)-3-(phenylamino)-5-(thiophen-2-ylmethylidene)-3,5-dihydro-4H-imidazol-4-one, C{sub 20}H{sub 14}N{sub 3}OSCl was synthesized and its crystal structure was determined by single crystal X-ray diffraction. The crystals are triclinic, sp. gr. P1, Z = 2. All three rings are planar, and imidazole ring is almost perpendicular to the phenyl ring with the dihedral angle of 88.65(2)°. In the crystal, pairs of O–H···O hydrogen bonds link molecules into inversion dimers, featuring R{sub 22}(10) graph set motif. Crystal structure is further stabilized by π···π interactions.

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

Hydrothermal Synthesis and Characterization of a New Strandberg-type Diphosphopentamolybdate (C{sub 6}N{sub 3}H{sub 18}){sub 2}[P{sub 2}Mo{sub 5}O{sub 23}] · 6H{sub 2}O

An inorganic-organic hybrid material formulated as (C{sub 6}N{sub 3}H{sub 18}){sub 2}[P{sub 2}Mo{sub 5}O{sub 23}] · 6H{sub 2}O, has been hydrothermally synthesized and characterized by single crystal X-ray diffraction technique, IR spectrum, thermogravimetric analysis and UV-visible spectroscopy. The structure consists of diphosphopentamolybdate Strandberg type polyoxoanions [P{sub 2}Mo{sub 5}O{sub 23}]{sup 6–}, protonated 1-(2-aminoethyl)piperazine cations and six crystallization water molecules. These anions are connected with the organic amine through hydrogen bonding interactions between the hydrogen atoms of the organic molecules and the oxygen atoms of the polyoxoanion and water molecules which generate a three-dimensional network.

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

New Diphosphopentamolybdate K{sub 5}[HP{sub 2}Mo{sub 5}O{sub 23}] · 10H{sub 2}O: Synthesis, Structure, and Characterization

A new diphosphopentamolybdate(VI) K{sub 5}[HP{sub 2}Mo{sub 5}O{sub 23}] · 10H{sub 2}O has been prepared employing solution method and characterized by single crystal X-ray diffraction, energy dispersive analysis, infrared spectroscopy, thermal stability analysis, cyclic voltammetry analysis, and ultraviolet visible spectroscopy. The compound crystallizes in the orthorhombic sp. gr. Pcab: a = 15.9661(10) Å, b = 19.0832(10) Å, c = 20.0970(9) Å, V = 6123.27(10) Å3, Z = 8. The crystal structure contains the polyanion units [HP{sub 2}Mo{sub 5}O{sub 23}]{sup 5–} around the potassium cations and lattice water. The [HP{sub 2}Mo{sub 5}O{sub 23}]{sup 5–} subunits are connected together through K−O−Mo bridges and hydrogen bonds. The crystal shape morphology was simulated using the Bravais–Friedel–Donnay–Harker model.

36 MATERIALS SCIENCE↗
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

A Novel Coordination Polymer Based on Trinuclear Cobalt Building Blocks Cluster: Synthesis, Crystal Structure, and Properties

The title compound {[Co_3(μ_3-OH)(μ_2-H_2O)2(H_2O)_5(BTC)_2] · 6H_2O}{sub n} (H{sub 3}BTC is a 1,3,5-benzenetricarboxylic acid) was prepared and characterized by single crystal and powder X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric and elemental analyses. The single crystal X-ray diffraction reveals that the title compound consists of 1D infinite zigzag chains which were constructed by trinuclear cobalt cluster and BTC{sup 3–} ligand. Neighbouring above-mentioned 1D infinite zigzag chains are further linked by intermolecular hydrogen bonding to form a 3D supermolecular structure. In addition, the luminescent properties of the title compound were investigated.

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

SEM, Chemical Etching and THz Wave Generation of 4-Dimethylamino-N-methyl-4-stilbazolium Tosylate (DAST) Single Crystals

The 4-dimethylamino-N-methyl-4-stilbazolium tosylate (DAST) crystal which was candidate for generating and detecting terahertz (THz) wave was grown by slope nucleation method (SNM). The functional groups of DAST were identified by Fourier Transform Infrared (FTIR) studies. Macroscopic steps and streaks on the (001) face were found by scanning electron microscope (SEM). Different patterns of etch pits under different chemical etchants were studied by optical microscope. Widely tunable THz waves ranging from 0.38 to 18.10 THz were generated from 0.5 mm-thick DAST crystal. The maximum output energy was 345.4 nJ/pulse at 3.39 THz and the conversion efficiency was 8.44 × 10{sup –5}.

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

Single Crystal X-ray Study of 6-Phenyl-4-(p-tolyl)pyridin-2(1H)-one

The title compound 6-phenyl-4-(p-tolyl)pyridin-2(1H)-one was synthesized via one-pot, three component reaction of (E)-1-phenyl-3-(p-tolyl)-2-propen-1-one, ethyl 2-nitroacetate and ammonium acetate in refluxing ethanol, as a shiny green crystalline solid in 83% yield. Its structure was characterized by spectral studies and unambiguously corroborated by X-ray diffraction crystallography. The crystals of title compound are monoclinic, sp. gr. P2{sub 1}/n, a = 11.8346(7) Å, b = 13.4413(9) Å, c = 17.7626(10) Å, β = 99.479(5)°, and Z = 8. All the rings in molecule of the title compound are planar. Hydrogen interactions play significant role in stabilizing the crystal structure and the supramolecular aggregate of molecules is facilitated by strong N–H···O and C–H···O type of hydrogen interactions.

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 OSTI2017

Condensation Reaction of 1,2,3,4-Tetrahydro-1,10-phenanthroline and Formaldehyde: Synthesis and Crystal Structures of Bis(1,2,3,4-tetrahydro-1,10-phenanthroline-6-yl)methane and Its p-Toluenesulfonate Salt

A new heterocyclic compound, bis(1,2,3,4-tetrahydro-1,10-phenanthroline-6-yl) methane (1), was obtained by the condensation reaction of 1,2,3,4-tetrahydro-1,10-phenanthroline (tphen) and formaldehyde (HCHO). The p-toluenesulfonate salt of 1, (ptsa){sub 2} · (1H{sub 2}) (2, ptsaH = p-toluenesulfonic acid), is also synthesized and characterized. Cystal structures of 1 and 2 are determined by X-ray single crystal diffraction. The molecules of 1 form a 1D helix supramolecular chain by weak N−H···N hydrogen bonds, while in crystal 2, the 1H{sub 2}{sup 2+} cations and ptsa{sup -} anions are alternately connected by strong N−H···O hydrogen bonds and generate a 1D zigzag supramolecular chain. The result also proves that the condensation reaction of tphen can provide its C6 condensation product with high regioselectivity.

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

Synthesis, Structure, and Fluorescence of a Novel Cadmium Compound

A novel cadmium compound, [(CdI{sub 3}){sub 2}(μ{sub 2}-I)]{sub 2}(Me{sub 2}-4,4'-H{sub 2}bipy){sub 3} (1) (Me = methyl; 4,4'-bipy = 4,4'-bipyridine) with the Me{sub 2}-4,4'-H{sub 2}bipy moiety generated in situ, has been prepared through a solvothermal reaction and structurally characterized by X-ray single crystal diffraction analysis. Compound 1 is characterized by an isolated structural motif, consisting of [(CdI{sub 3}){sub 2}(μ{sub 2}-I)]{sup 3–} anions and Me{sub 2}-4,4'-H{sub 2}bipy{sup 2+} cations. The [(CdI{sub 3}){sub 2}(μ{sub 2}-I)]{sup 3–} anions and Me{sub 2}-4,4'-H{sub 2}bipy{sup 2+} cations interconnect together via C–H···I hydrogen-bonding interactions to complete a three-dimensional (3D) supramolecular network. Solid state fluorescent spectrum reveals an emission band in the violet region.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Structural Analysis of Sr{sub 3}NbFe{sub 3}Si{sub 2}O{sub 14} Single Crystal from the Langasite Family and Finding of Negative Thermal Expansion in the Range of 83–110 K

Iron-containing Sr{sub 3}NbFe{sub 3}Si{sub 2}O{sub 14} single crystals from the langasite family, which are interesting for researchers due to their magnetic ordering at T{sub N} = 26 K, have been grown by the floating zone melting method. Accurate X-ray diffraction analysis is performed at 293 and 90.5 K using the data collected on a CCD diffractometer. To compensate for systematic errors, two data sets are collected at each temperature. The structure is refined based on averaged data set: sp. gr. P321, Z = 1, sin θ/λ ≤ 1.35 Å{sup –1}; a = 8.2609(4) Å, c = 5.1313(3) Å at 293 K and a = 8.2344(6) Å, c = 5.1243(6) Å at 90.5 K; the agreement factors are R/wR = 1.18/1.03% and Δρ{sub min}/Δρ{sub max} =–0.57/0.25 e/Å3 for 3583 independent reflections at 293 K and R/wR = 1.18/1.13% and Δρ{sub min}/Δρ{sub max} =–0.54/0.23 e/Å3 for 3638 reflections at 90.5 K. Negative thermal expansion in the direction of the cell c axis is revealed in the range of 83–110 K.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Growth from Solution, Structure, and Optical Properties of Single-Crystal para-Quaterphenyl Films

Samples of single-crystal para-quaterphenyl films up to 8 mm long and 50 μm thick have been obtained for the first time by the solvent‒antisolvent growth method. The films have been grown both on the liquid–air interface and in the solution bulk. The morphology, surface quality, and thickness of crystal films have been investigated by the optical, laser confocal, and atomic force microscopies. The structure of the para-quaterphenyl single crystal at room temperature has been refined by X-ray diffraction analysis. The formation and growth mechanisms of crystal films on the liquid–air interface have been discussed. The opticalabsorption and photoluminescence spectra of the solutions and crystal samples have been investigated.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Synthesis and Electrical Properties of a Fluorite-Like Nd{sub 5}Mo{sub 3}O{sub 16} Compound with Partial Substitution of Molybdenum by Tungsten, Niobium, or Vanadium

The phase formation of Nd{sub 5}Mo{sub 3–x}W{sub x}O{sub 16.5}, Nd{sub 5}Mo{sub 3–x}Nb{sub x}O{sub 16.5–х/2}, and Nd{sub 5}Mo{sub 3–x}V{sub x}O{sub 16.5–х/2} solid solutions based on a fluorite-like Nd{sub 5}Mo{sub 3}O{sub 16.5} compound (mixed conductor with interstitial oxygen conductivity) has been studied. The electrical conductivity of doped compounds obeys the Arrhenius law and, at a low impurity content, is as high as 0.03–0.08 S/cm at 800°C. Substitution of Mo{sup 6+} cations by V{sup 5+} and Nb{sup 5+} cations reduces the interstitial oxygen content, which causes a decrease in the solid-solution electrical conductivity by 1–2 orders of magnitude and a decrease in the cubic unit-cell parameter. A wide diffuse anomaly with a maximum of about 1500–4000 has been observed in the temperature dependence of the permittivity for all single-crystal and polycrystalline samples in the range of 300–900°C.

36 MATERIALS SCIENCE↗