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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Aluminum hydrides with radical-anionic and dianionic acenaphthene-1,2-diimine ligands

The reaction of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-bian) with LiAlH{sub 4} affords two products regardless of the solvent used (tetrahydrofuran or diethyl ether). These products were isolated as green and colorless crystals. Green crystals of the complex [(dpp-bian)Al(H){sub 2}Li(THF){sub 3}] (1) were obtained from tetrahydrofuran; colorless crystals of the complex [{dpp-bian(H_2)}Al(H){sub 2}Li(Et{sub 2}O){sub 2}] (2), from diethyl ether. The reactions of compound 1 with 2,6-di-tert-butyl-4-methylphenol and benzophenone gave monohydrides [(dpp-bian)Al(H)(OC{sub 6}H{sub 2}-2,6-Bu{sub 2}{sup t}-4-Me)][Li(THF){sub 4}] (3) and [(dpp-bian)Al(H)(OCHPh{sub 2})- Li(THF){sub 2}] (4), respectively. The diamagnetic aluminum hydride [(dpp-bian)AlH(THF)] (5) was synthesized by the reaction of dichloroalane HAlCl{sub 2} (in situ) with the disodium salt of dpp-bian in THF; the paramagnetic hydride [(dpp-bian)AlH(Cl)] (6) containing the dpp-bian radical anion was synthesized by the reaction of the monosodium salt (dpp-bian)Na with monochloroalane H{sub 2}AlCl (in situ) in diethyl ether. The reaction of compound 6 with tert-butyllithium gives the complex [(dpp-bian)AlBu{sup t}(Et{sub 2}O)] (7). Diamagnetic derivatives 1—5 and 7 were characterized by {sup 1}Н NMR spectroscopy; paramagnetic compound 6, by ESR spectroscopy. The molecular structures of compounds 1—7 were determined by single-crystal X-ray diffraction.

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

Cadmium(II) terephthalates based on trinuclear units {Cd_3(bdc)_3}: control of coordination structure dimensionality and luminescence properties

Two metal-organic coordination polymers based on cadmium(II) ions and terephthalic (1,4-benzenedicarboxylic) acid were synthesized in dimethylformamide or a mixture of dimethylformamide and methanol: [Cd{sub 3}(bdc){sub 3}(dmf){sub 4}] (1, bdc is 1,4-benzenedicarboxylate, dmf is N,N´-dimethylformamide) and [Cd{sub 3}(bdc){sub 3}(dmf){sub 2}] (2), respectively. According to the single-crystal X-ray diffraction data, both compounds are built up by the trinuclear carboxylate units {Cd_3(O_2CR)_6}. Compound 1 has a layered structure, whereas compound 2 has a three-dimensional structure due to the presence of additional coordination interactions between adjacent trinuclear units and the formation of polymer chains {Cd_3(dmf)_2(μ_2-O_2CR-κ"1,κ"1)_2(μ_2-O_2CR-κ"2,κ"1)_4(O_2CR-κ"1)2}. The synthesized compounds were characterized by IR spectroscopy, thermogravimetric analysis, elemental analysis, and powder X-ray diffrac- tion. The luminescence properties of these compounds provide evidence for the existence of both intraligand and charge-transfer transitions. The luminescence quantum yields for both compounds are 10%.

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

Ternary gallides of the Ce{sub 2+n}Rh{sub 3+3n}Ga{sub 1+2n} (n = 0—5) structure family

The structures of nine ternary intermetallic compounds (IMCs) of the cerium—rhodium—gallium system containing 50 at.% rhodium were determined by single-crystal X-ray diffraction. The compounds are built up of alternating Ce{sub 2}Rh{sub 3}Ga fragments with the Mg{sub 2}Cu{sub 3}Si (MgZn{sub 2} type) or Mg{sub 2}Ni{sub 3}Si (MgCu{sub 2} type) structure and CeRh{sub 3}Ga{sub 2} fragments with the CeCo{sub 3}B{sub 2} (CaCu{sub 5} type) structure and form a homologous series of the composition R{sub 2+n}T{sub 3+3n}M{sub 1+2n} (n = 0—5). These compounds can be classified into trigonal (R-3m) or hexagonal (P6{sub 3}/mmc) branches depending on the Laves phase-type fragment.

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

Three-dimensional copper(II) carboxylates based on 4,4′,4″-benzene-1,3,5-triyltris(benzoic acid)

The homochiral coordination polymers [Cu{sub 4}(CH{sub 3}OH)(H{sub 2}O){sub 4}(Hbtb)(S-mal){sub 2}]•4H{sub 2}O and [Cu{sub 4}(CH{sub 3}OH)(H{sub 2}O){sub 4}(Hbtb)(R-mal){sub 2}]•4H{sub 2}O were synthesized by heating S- or R-malic acid (H{sub 3}mal), 4,4′,4″-benzene-1,3,5-triyltris(benzoic acid) (H{sub 3}btb), and copper(II) acetate in an aqueous methanolic solution. The reaction with copper(II) nitrate in aqueous dioxane afforded the coordination framework [Cu{sub 6}(C{sub 4}H{sub 8}O{sub 2}){sub 3}(H{sub 2}O){sub 3}(btb){sub 4}]•4C{sub 4}H{sub 8}O{sub 2}•10H{sub 2}O, which does not contain chiral ligands. The compositions and crystal structures of the new compounds were determined by single-crystal X-ray diffraction and confirmed by X-ray powder diffraction, IR spectroscopy, thermogravimetric and elemental analysis.

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

Synthesis and crystal structure of the coordination polymer [{Li(H_2O)_3}{sub 2}(C{sub 36}H{sub 36}N{sub 24}O{sub 12})]Cl{sub 2}•6H{sub 2}O

The coordination polymer of the composition [{Li(H_2O)_3}{sub 2}(C{sub 36}H{sub 36}N{sub 24}O{sub 12})]Cl{sub 2}•6H{sub 2}O (1) was synthesized by heating an aqueous solution of lithium chloride and cucurbit[6]uril (CB[6]). According to single-crystal X-ray diffraction data, solvated lithium cations in compound 1 form coordination bonds with oxygen atoms of CB[6] molecules. Compound 1 was characterized by X-ray diffraction, IR spectroscopy, thermogravimetric and elemental analysis. Luminescence spectra of the new compound were measured.

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

Coordination polymers based on zinc(II) and manganese(II) with 1,4-cyclohexanedicarboxylic acid

Three new metal-organic coordination polymers were obtained namely, [Mn{sub 3}(chdc){sub 3}-(NMP){sub 2}(DMF){sub 2}] (1, chdc{sup 2–} is trans-1,4-cyclohexanedicarboxylate, NMP is N-methylpyrrolidone, DMF is N,N-dimethylformamide), [Zn{sub 3}(chdc){sub 3}(NMP){sub 2}]•2NMP (2), and [Zn{sub 3}(chdc){sub 3}(ur)-(DMF){sub 0.5}]•DMF (3, ur is the urotropine). The crystal structures of polymers 1, 2, and 3 were determined by single-crystal X-ray crystallography. All three compounds were found to contain a trinuclear secondary building unit {M_3(OOC)_6}. Coordination polymers 1 and 2 have a layered structure, while polymer 3 has a three-dimensional coordination framework with isolated pores formed due to the presence of urotropine bridging molecules. Compounds 1 and 3 were characterized by IR spectroscopy, thermogravimetric and elemental analysis data, powder X-ray diffraction. Compound 3 was also characterized by UV-Vis diffuse reflectance spectrum.

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

Synthesis and structural features of new pentacoordinated monofluorosilanes containing C,O-chelate ligands based on 2-amino acid N-methylamides

Pentacoordinated monofluorosilanes R{sup 1}SO{sub 2}NHCHR{sub 2}C(O)N(Me)CH{sub 2}SiMe{sub 2}F containing moieties of N′-methyl-N-(organosulfonyl)-2-amino acid amides of glycine, alanine, and leucine as C,O-chelating ligands were synthesized via the reaction of corresponding disiloxanes with BF{sub 3}•Et{sub 2}O. The structures of obtained compounds were investigated by single-crystal X-ray diffraction analysis.

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

New benzo[f]quinolino[3,4-b][1,7]naphthyridine-6,8(5H,9H)-diones: synthesis, electronic, molecular, and crystal structures. Protonation and complexation with lanthanum and europium salts

A series of novel benzo[f]quinolino[3,4-b][1,7]naphthyridine-6,8(5H,9H)-diones, which are promising ligands for the extractive separation of actinides and lanthanides, and also their complexes with lanthanum and europium were synthesized. The molecular and crystal structures of one among the ligands were determined by single crystal X-ray diffraction. The protonation of compounds was investigated by IR and NMR spectroscopy. The electronic structure of starting substances and protonated forms was estimated by DFT calculations.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Sterically hindered tetrylenes based on new 1,10-phenanthroline-containing diols: initiators for ε-caprolactone polymerization

Previously unknown tetradentate ONNO-type ligands 1–5 (4,7-di(4-R´-phenoxy)-2,9- di(HOCR{sub 2}CH)-1,10-phenanthrolines (R´ = Me, R–R = –(CH{sub 2}){sub 5}– (1), R = Me (2), R–R = 2,2-adamantylene (3); R´ = But, R–R = –(CH{sub 2}){sub 5}– (4), R = Me (5)) were synthesized by sequential treatment of 2,9-dimethyl-4,7-di(4-R´-phenoxy)-1,10-phenanthrolines 6 (R´ = Me) and 7 (R´ = Bu{sup t}) with excess LDA and appropriate dialkyl ketone. The structure of compound 4 was determined by single-crystal X-ray diffraction. Previously uncharacterized phenanthroline 6 was synthesized by the treatment of 4,7-dichloro-2,9-dimethyl-1,10-phenanthroline with excess p-cresol in the presence of KOH. The reaction of compounds 1–5 with one equivalent of Lappert´s germylene or stannylene, M[N(SiMe{sub 3}){sub 2}]{sub 2} (M = Ge, Sn), gave the corresponding germylenes 8–12 (M = Ge, R´ = Me, R–R = –(CH{sub 2}){sub 5}– (8), R = Me (9), R–R = 2,2-adamantylene (10), R´ = Bu{sup t}, R{sub 2} = –(CH{sub 2}){sub 5}– (11), R = Me (12)) and stannylenes 13–17 (M = Sn, R´ = Me, R–R = –(CH{sub 2}){sub 5}– (13), R = Me (14), R–R = 2,2-adamantylene (15), R´ = Bu{sup t}, R–R = –(CH{sub 2}){sub 5}– (16), R{sub 2} = Me (17)) in satisfactory yields. According to {sup 1}H, {sup 13}C, and {sup 119}Sn NMR data, the synthesized stannylenes are monomeric in solution, and the tin atom has a coordination number of 4. In the series of the compounds under consideration, stannylene 16 proved to be the most active initiator for e-caprolactone polymerization, whereas the germylenes were shown to be inactive in this process.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Binding of gold(III) with silver(I) dipropyldithiocarbamate: supramolecular self-assembly (role of secondary Au…S and Ag…S bonds) and thermal behavior of the ionic-polymer complex ([Au(S{sub 2}CNPr{sub 2}){sub 2}][AgCl{sub 2}]){sub n}

The double ionic-polymer complex ([Au(S{sub 2}CNPr{sub 2}){sub 2}][AgCl{sub 2}]){sub n} (1) was prepared as an individual fixation form of gold(III) from NaCl solutions with silver(I) dipropyldithiocarbamate and was characterized by single-crystal X-ray diffraction and {sup 13}C magic-angle spinning (MAS) NMR spectroscopy. The structure of 1 comprises two nonequivalent centrosymmetric complex cations [Au(S{sub 2}CNPr{sub 2}){sub 2}]{sup +} (A and B) and the discrete linear anion [AgCl{sub 2}]{sup –}. Gold(III) cations are linked by pairs of unsymmetrical secondary Au…S bonds to form linear supramolecular chains (…A…B…)n. Neighboring cations are additionally linked by [AgCl{sub 2}]{sup –} anions via secondary Ag…S and Cl…S bonds, the anions being involved in the overall stabilization of the supramolecular structure. The cation–anion interactions lead to a distortion of the linear configuration of the [AgCl{sub 2}]{sup –} anion. The character of thermolysis of 1 accompanied by quantitative regeneration of bound Au and Ag was established by simultaneous thermal analysis.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Metal-organic frameworks based on magnesium(II): adsorption and luminescence properties

Two new metal-organic frameworks based on magnesium(II) ions, [Mg{sub 4}(bdc){sub 3}(dma){sub 6}(NO{sub 3}){sub 2}]•DMA (1; bdc is 1,4-benzenedicarboxylate; dma, DMA is N,N-dimethylacetamide) and [Mg{sub 3}(bpdc){sub 3}(nmp){sub 4}] (2; bpdc is 4,4´-biphenyldicarboxylate; nmp is N-methylpyrrolidone), were synthesized in DMA or NMP, respectively. According to the single-crystal X-ray diffraction data, compound 1 is built of binuclear carboxylate units {Mg_2(O_2CR)_3}, which were previously not observed in metal-organic frameworks. Compound 2 is based on trinuclear carb oxylate units {Mg_3(O_2CR)_6}. Compound 1 has a layered structure (hcb topology), whereas compound 2 has a distorted three-dimensional cubic structure (pcu topology). The phase purity and chemical identity of the compounds were confirmed by IR spectroscopy, thermogravimetry, elemental analysis, and powder X-ray diffraction. Photoluminescence properties of both compounds are indicative of intraligand charge-transfer transitions of one (for 1) or two (for 2) types. Textural characteristics of an activated sample of 1 were measured by nitrogen and hydrogen adsorption at 77 K and by carbon dioxide adsorption at 195 K.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Decarboxylation and electrophilic substitution in 3-tert-butyl-4-oxopyrazolo[5,1-c][1,2,4]triazines

Reactivity of 7-R-3-tert-butyl-4-oxo-4,6-dihydropyrazolo[5,1-c][1,2,4]triazine-8-carboxylic acids (R = NH{sub 2}, N{sub 3}, H) and products of their decarboxylation towards different electrophilic agents (chloroacetone, Boc{sub 2}O/NaN{sub 3}, DMF/POCl{sub 3}, TMSBr, N-halosuccinimides, and HNO{sub 2}) was studied. A selective synthesis of new C(7),C(8)-functionalized and N(1)-tert-butyloxycarbonyl-substituted 4-oxopyrazolo[5,1-c][1,2,4]triazines was performed. The structures of the synthesized compounds were confirmed by IR and NMR spectroscopy, high resolution mass spectrometry and single crystal X-ray diffraction analysis.

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

Electrical and Thermal Conductivity of Solid Solution Sn{sub 1–x}Mn{sub x}Te (0 ≥ x ≥ 0.04)

Electrical and thermal properties of the Sn{sub 1–x}Mn{sub x}Te single crystals (0 ≥ x ≥ 0.04) with contacts of eutectic alloy 57Bi + 43Sn (in mass%) are investigated at temperatures from 77 to 300 K. Experimental results show that this alloy with specified single crystals forms ohmic contact with a sufficiently low contact resistance. The electronic thermal conductivity in some samples reaches about 50% of the total thermal conductivity, and structural defects contribute significantly to the thermal resistance of the crystals.

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DOE OSTI2018

A New Method of Obtaining an n–p-Structure on the Basis of the Defective Semiconductor AgIn{sub 5}S{sub 8}

The type of electrical conductivity of А{sup 1}В{sup 3}{sub 5}С{sup 6}{sub 8} semiconductor compounds with defective crystalline structure is modified by the influence of powerful laser radiation. It is shown that at certain power and wavelength of laser radiation acting on the single-crystal п-AgIn{sub 5}S{sub 8}, an area with the p-type of conductivity is formed in the irradiated region of the crystal. Current-voltage characteristics of homo-junctions created on the basis of n-AgIn{sub 5}S{sub 8} are recorded.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Influence of After-Growth Treatments on the Optical Parameters of Teraherz ZnGeP{sub 2} Crystals

Results of investigations are presented of the THz spectra of the refractive index n(v) and of the extinction coefficient k(v) for ZnGeP{sub 2} single crystals with different degrees of technological treatment – after growth by the vertical Bridgman technique, after heat treatment at temperatures above the Debye temperature for the highest-frequency phonons, and after modification of the single-crystal properties under irradiation by fast electrons (~4 MeV).

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

An Analysis of Characteristics of Magnetostatic Waves Propagating in Nonhomogeneous Fields Across the Ferrospinel Film Thickness

The amplitude-frequency characteristics (AFCs) of magnetostatic waves in the films of magnesium-manganese ferrospinels with nanostructured inhomogeneities are discussed. A common effect, observed in the film AFCs under different process conditions, is the ‘oscillations of propagation’ of magnetostatic waves as a function of the frequency. The oscillation pattern is thought to depend on the inhomogeneous exchange parameters and the surface anisotropy constants. The wave instability is characterized by the resonant interaction of the dipole magnetostatic waves with the surface spin waves. It is shown that the ferrospinel films with periodic nanostructured inhomogeneities of 30–40 nm could be treated as magnon crystals. An inclusion of the inhomogeneity into consideration allows one to provide reasoning for the formation of the rejection bands within the range 9–12 GHz, whose frequencies correspond to Bragg frequencies.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2018

Estimation of Crystal Lattice Deformations with Depth of Proton-Exchanged Optical Waveguides on Lithium Niobate Single Crystal Substrates

A method for determining the crystal phase and estimating the crystal lattice deformations in H{sub x}Li{sub 1-x}NbO{sub 3} proton-exchanged optical waveguides from an analysis of the Raman light scattering spectra measured with high spatial resolution (the so-called method of micro-RS spectroscopy) is suggested.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2019

Structural and Phase Transformations in Superlocalization Band in Ni{sub 3}Ge Single Crystal

The paper studies the high-temperature plastic deformation in Ni{sub 3}Ge alloy single crystals localizing in a band a few tens of microns wide that reaches the shear strain of thousands of percent. The electron backscatter diffraction and synchrotron radiation techniques allow investigating the structure of the single crystal in the band of super-localized plastic deformation. It is shown that super-localization of plastic deformation occurs due to the formation of polycrystalline multi-level substructure in the initial single crystal. The grain size and grain misorientation bimodal distributions are determined in the polycrystalline substructure. Also, regions of amorphous state are observed in the super-localization band at high homologous temperature Т > 0.5T{sub m}. A partial destruction of the far atomic order is detected.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗