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31.
Mironov YV Yarovoi SS Naumov DY Kozlova SG Ikorsky VN Kremer RK Simon A Fedorov VE 《The journal of physical chemistry. B》2005,109(50):23804-23807
The novel vanadium thiobromide, V4S9Br4, with a square-planar metal cluster core was synthesized and characterized by single-crystal X-ray diffraction, measurements of magnetic properties and the heat capacity, and DFT calculations of the electronic structure. At the room temperature, the compound displays paramagnetic properties with an independent spin on each V atom and with a weak exchange constant (J approximately 10 cm(-1)). The paramagnetic state is transformed into a low-spin state (AF-type ordering) at low temperatures. This change is accompanied by a heat-capacity anomaly. The observed magnetic and heat-capacity anomalies can be explained by the thermal excitation of electrons on the closely spaced molecular energy levels in the presence of the Jahn-Teller effect. 相似文献
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B. S. Fedorov M. A. Fadeev V. V. Arakcheeva G. V. Strukov N. I. Golovina R. F. Trofimova G. V. Shilov L. O. Atovmyan 《Russian Chemical Bulletin》1994,43(12):2087-2090
A novel heterocyclic compound, 4-acetoxy-5,6-dihydro-5,5-dinitro-2H-1,3-oxazineN-oxide, has been synthesized by the reaction of the dipotassium salt of 1,1,5,5-tetranitro-3-oxapentane with aqueous acetic acid. The synthesized compound has been studied by X-ray diffraction analysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2207–2210, December, 1994.We would like to thank G. V. Lagodzinskaya (Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences) for recording and interpreting1H NMR spectra, A. M. Korolev (Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences) for helpful discussion, and V. I. Fetisov (Institute of Physiologically Active Compounds, Russian Academy of Sciences) for performing quantum-chemical calculations by the AM1 SCF MO LCAO method. 相似文献
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A. Yu. Fedorov J. -P. Finet O. G. Ganina M. I. Naumov A. S. Shavyrin 《Russian Chemical Bulletin》2005,54(11):2602-2611
Benzopyran derivatives were synthesized in good yields by the reactions of tris[2-(chloromethyl)phenyl]bismuth diacetate and
2-(halomethyl)aryllead triacetates with phenols and naturally occurring 4-hydroxycoumarins in the presence of bases according
to a three-step one-pot procedure.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2520–2529, November, 2005. 相似文献
38.
Kanitskaya L. V. Elokhina V. N. Fedorov S. V. Shulunova A. M. Nakhmanovich A. S. Turchaninov V. K. Lopyrev V. A. 《Russian Journal of General Chemistry》2002,72(5):778-784
Pyridine was reacted with propargyl bromide to obtain the dibromide [C5H5NCH = CHCH = CHCH = CHC5H5N]2
+ 2Br-. The effect of the vinyl group on its UV spectrum is qualitatively interpreted using the results of nonempirical quantum-chemical calculations (basis HF/6-31G*). 相似文献
39.
Yu. V. Fedorov O. A. Fedorova N. E. Shepel’ S. P. Gromov M. V. Alfimov L. G. Kuz’mina J. A. K. Howard J. Saltiel 《Russian Chemical Bulletin》2005,54(9):2119-2128
Benzobisthiazole-based bis(crown ether) was synthesized and its complexation with alkali and alkaline earth cations was studied.
Photochemical transformations of the free ligand and its complexes with alkaline earth cations involve E,Z-photoisomerization and [2+2] photocycloaddition.
Dedicated to Academician N. S. Zefirov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2056–2065, September, 2005. 相似文献
40.
É. I. Fedin P. V. Petrovskii L. A. Fedorov Yu. V. Makarov N. E. Kolobova K. N. Anisimov 《Russian Chemical Bulletin》1973,22(9):2093-2095
Conclusions The electron density on the-cyclopentadienyl ligand in cyclopentadienylmanganese tricarbonyl derivatives is higher than in the corresponding cyclopentadienylrhenium tricarbonyl derivatives.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2142–2143, September, 1973. 相似文献