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K10Ga3Bi6.65 is the first representative in the ternary system A-Ga-Bi (A = alkali metal). It contains [Ga3Bi6]9– anions with planar triangular-coordinated Ga atoms as the main structural feature, accompanied by isolated Bi–Bi dumbbells. Alkali metal cations are counterbalancing the charges and fill the space between the anionic units. According to the Zintl-Klemm concept charge balance is reached if an almost equal ratio of single and double-bonded Bi2 dumbbells are present according to (K+)10[Ga3Bi6]9–([Bi-Bi]4–)1/6([Bi=Bi]2–)1/6. 相似文献
44.
Babushkina Anastasia A. Mikhaylov Vladimir N. Novikov Alexander S. Sorokoumov Viktor N. Gureev Maxim A. Kryukova Mariya A. Shpakov Alexander O. Balova Irina A. 《Chemistry of Heterocyclic Compounds》2022,58(8-9):432-437
Chemistry of Heterocyclic Compounds - The Richter cyclization was used for the synthesis of 6-halo-3-(hydroxymethyl)cinnolin-4(1H)-ones. X-ray analysis revealed that these compounds exist as dimers... 相似文献
45.
Bojan Šoptrajanov Gligor Jovanovski Viktor Stefov Igor Kuzmanovski 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract The infrared (IR) and Raman spectra of MgHPO4. 3H2O and of a series of partially deuterated analogues as well as the IR spectra of MnHPO4. 3H2O have been recorded and interpreted. The analysis of the IR spectra in the HOD bending region rules out the possibility of existence of H3OC+ ions in the structure. 相似文献
46.
Nickolay I. Tyryshkin Viktor V. Gavrilov Alexandra V. Fuzhenkova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract It has been known more than for 100 year that triethylphosphine forms the 1:1 adducts with carbon disulfide and isothiocyanates. However, little is know on the reaction of the adducts and the formation of reactive alkylidenephosphoranes was recently reported by the reaction of adducts with electron-poor double bonds. 相似文献
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Ilya G. Ryabinkin Viktor N. Staroverov 《International journal of quantum chemistry》2013,113(11):1626-1632
The differential virial theorem (DVT) is an explicit relation between the electron density ρ( r ), the external potential, kinetic energy density tensor, and (for interacting electrons) the pair function. The time‐dependent generalization of this relation also involves the paramagnetic current density. We present a detailed unified derivation of all known variants of the DVT starting from a modified equation of motion for the current density. To emphasize the practical significance of the theorem for noninteracting electrons, we cast it in a form best suited for recovering the Kohn–Sham effective potential vs( r ) from a given electron density. The resulting expression contains only ρ( r ), vs( r ), kinetic energy density, and a new orbital‐dependent ingredient containing only occupied Kohn–Sham orbitals. Other possible applications of the theorem are also briefly discussed. © 2012 Wiley Periodicals, Inc. 相似文献
50.
Evgeny V. Shchegol'kov Anna E. Ivanova Yanina V. Burgart Viktor I. Saloutin 《Journal of heterocyclic chemistry》2013,50(Z1):E80-E86
Azo coupling of 1,3‐dicarbonyl compounds with tetrazolyl‐5‐diazonium chloride is used to develop a convenient one‐step procedure for the synthesis of 4,7‐dihydrotetrazolo[5,1‐c][1,2,4]triazines. In contrast to nonfluorinated analogs, 7‐hydroxy‐7‐polyfluoroalkyl‐4,7‐dihydrotetrazolo[5,1‐c][1,2,4]triazines undergo a ring‐chain isomerism resulting from the cleavage at the C7―N7a bond. A distinctive feature of nonfluorinated 4,7‐dihydrotetrazolo[5,1‐c][1,2,4]triazines is the possibility to dehydration, which is accompanied by an azide rearrangement due to the tetrazole ring cleavage with the formation of tetrazolo[1,5‐b][1,2,4]triazines. 相似文献