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91.
92.
Kurnosov AV Ogienko AG Goryainov SV Larionov EG Manakov AY Lihacheva AY Aladko EY Zhurko FV Voronin VI Berger IF Ancharov AI 《The journal of physical chemistry. B》2006,110(43):21788-21792
Dissociation temperatures of gas hydrate formed in the ethane-water system were studied at pressures up to 1500 MPa. In situ neutron diffraction analysis and X-ray diffraction analysis in a diamond anvil cell showed that the gas hydrate formed in the ethane-water system at 340, 700, and 1840 MPa and room temperature belongs to the cubic structure I (CS-I). Raman spectra of C-C vibrations of ethane molecules in the hydrate phase, as well as the spectra of solid and liquid ethane under high-pressure conditions were studied at pressures up to 6900 MPa. Within 170-3600 MPa Raman shift of the C-C vibration mode of ethane in the hydrate phase did not show any discontinuities, which could be evidence of possible phase transformations. The upper pressure boundary of high-pressure hydrate existence was discovered at the pressure of 3600 MPa. This boundary corresponds to decomposition of the hydrate to solid ethane and ice VII. The type of phase diagram of ethane-water system was proposed in the pressure range of hydrate formation (0-3600 MPa). 相似文献
93.
94.
Experimental evidence for the formation of HXeCCH: the first hydrocarbon with an inserted rare-gas atom 总被引:1,自引:0,他引:1
Feldman VI Sukhov FF Orlov AY Tyulpina IV 《Journal of the American Chemical Society》2003,125(16):4698-4699
Combined FTIR and EPR studies of acetylene irradiated with fast electrons in a solid xenon matrix provide experimental evidence for the formation of HXeCCH, a novel-type organic molecule with an inserted rare-gas atom. The new species resulting from the reaction of H atoms with CCH radicals in xenon was characterized by an intense IR absorption at 1486.0 cm(-1) corresponding to Xe-H stretching. 相似文献
95.
Kristina F. Baranova Aleksei A. Titov Alexander F. Smolyakov Andrey Yu. Chernyadyev Oleg A. Filippov Elena S. Shubina 《Molecules (Basel, Switzerland)》2021,26(22)
A series of emissive Cu(I) cationic complexes with 3-(2-pyridyl)-5-phenyl-pyrazole and various phosphines: dppbz (1), Xantphos (2), DPEPhos (3), PPh3 (4), and BINAP (5) were designed and characterized. Complexes obtained exhibit bright yellow-green emission (ca. 520–650 nm) in the solid state with a wide range of QYs (1–78%) and lifetimes (19–119 µs) at 298 K. The photoluminescence efficiency dramatically depends on the phosphine ligand type. The theoretical calculations of buried volumes and excited states explained the emission behavior for 1–5 as well as their lifetimes. The bulky and rigid phosphines promote emission efficiency through the stabilization of singlet and triplet excited states. 相似文献
96.
Aleksei B. Sheremetev Elena V. Shatunova Boris B. Averkiev Dmitrii E. Dmitriev Viktor A. Petukhov Mikhail Yu. Antipin 《Heteroatom Chemistry》2004,15(2):131-145
A series of chromophoric azofurazan-containing macrocycles 6a–c and 7a–d were synthesized from bis(aminofurazanylic) ethers of 1,2-diols 4a–d by dibromoisocyanurate oxidation. The macrocycle closure is a result of NN bond formation. An ion-binding ability of these compounds was tested. The macrocycles were characterized by NMR, MS, IR, and UV spectroscopy. The X-ray crystal structures of the macrocycles 6a, 7c , and linear counterpart 12 are reported. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:131–145, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10226 相似文献
97.
Petro P. Onys'ko Aleksei A. Sinitsa Vladimir V. Pirozhenko Aleksandr N. Chernega 《Heteroatom Chemistry》2002,13(1):22-26
N‐Benzoyl‐ and N‐methoxycarbonyltrifluoroacetimidoylphosphonates react with dimethylcyanamide in a [4+2]‐cycloaddition to give 4‐phosphorylated 1,3,5‐oxadiazines. The structures of the products were confirmed by NMR (1H, 13C, 19F, 31P) and IR spectra and by XRD analysis. © 2002 John Wiley & Sons, Inc. Heteroatom Chem 13:22–26, 2002; DOI 10.1002/hc.1102 相似文献
98.
Andrei B. Koudriavtsev Andrei T. Teleshev Aleksei A. Zhdanov Eduard E. Nifant’ev Wolfgang Linert 《Monatshefte für Chemie / Chemical Monthly》2001,132(9):1001-1012
Summary. Complexation of Rh(I) with o, o′-dimethylene-(tris-p-cresyl)-bicyclophosphite (BCP, 1) has been investigated in solution by NMR, semi-empirical quantum mechanical, and molecular mechanics calculations. 1H and 31P NMR spectroscopic data show that when the BCP/Rh ratio exceeds 2, Rh hydride complexes of the composition RhH(BCP)3 and RhH(BCP)4 are formed. The source of the hydride ion is the ligand itself; most probably, H− originates from the bridging CH2 groups of BCP. The chemical shifts of these protons are sensitive to complexation due to the considerable electron density of HOMO and
LUMO at one of the bridging CH2 moieties. Molecular mechanics simulations of the molecular structure of these complexes show that two cavities are formed
in [Rh(BCP)3]+ by the aromatic rings of the ligands. These cavities may alternatively open and close, thus providing for a flexibly shielded
catalytic site which explains the unusual catalytic behaviour of Rh complexes with BCP in hydrogenation and hydroformylation reactions.
Received February 15, 2001. Accepted (revised) April 23, 2001 相似文献
99.
Andrei B. Koudriavtsev Andrei T. Teleshev Aleksei A. Zhdanov Eduard E. Nifant’ev Wolfgang Linert 《Monatshefte für Chemie / Chemical Monthly》2001,52(12):1001-1012
Complexation of Rh(I) with o, o′-dimethylene-(tris-p-cresyl)-bicyclophosphite (BCP, 1) has been investigated in solution by NMR, semi-empirical quantum mechanical, and molecular mechanics calculations. 1H and 31P NMR spectroscopic data show that when the BCP/Rh ratio exceeds 2, Rh hydride complexes of the composition RhH(BCP)3 and RhH(BCP)4 are formed. The source of the hydride ion is the ligand itself; most probably, H− originates from the bridging CH2 groups of BCP. The chemical shifts of these protons are sensitive to complexation due to the considerable electron density of HOMO and LUMO at one of the bridging CH2 moieties. Molecular mechanics simulations of the molecular structure of these complexes show that two cavities are formed in [Rh(BCP)3]+ by the aromatic rings of the ligands. These cavities may alternatively open and close, thus providing for a flexibly shielded catalytic site which explains the unusual catalytic behaviour of Rh complexes with BCP in hydrogenation and hydroformylation reactions. 相似文献
100.
Aleksei B. Sheremetev Natalya S. Aleksandrova Tatyana M. Melnikova Tatyana S. Novikova Yuri A. Strelenko Dmitrii E. Dmitriev 《Heteroatom Chemistry》2000,11(1):48-56
Nonselective attacks at the carbon bonded to a nitro group and carbon bonded to the N(O) atom of the azoxy group were observed in the reactions of 4,4′‐dinitroazoxyfurazan with bases and nucleophiles. A mechanism is presented to account for both of the pathways to products. A series of new difurazanyl ether derivatives was synthesized. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:48–56, 2000 相似文献