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Your search keyword '"Shcherbakov, A."' showing total 179 results
Start Over Author "Shcherbakov, A." Journal journal of structural chemistry
179 results on '"Shcherbakov, A."'

14. On the Influence of the Nature of Non-Bridging Donor Atoms on the Structure and Magnetic Properties of Binuclear Cu(II) Complexes with Heterocyclic Azomethine Ligands

Author

S. N. Lyubchenko, Yu. P. Tupolova, A. N. Morozov, Sergey I. Levchenkov, Leonid D. Popov, Igor N. Shcherbakov, and E. A. Raspopova

Subjects
Solid-state physics, Ligand, chemistry.chemical_element, Copper, Ion, Inorganic Chemistry, Metal, Crystallography, Oxygen atom, chemistry, visual_art, Materials Chemistry, visual_art.visual_art_medium, Antiferromagnetism, Physical and Theoretical Chemistry
Abstract

Binuclear complex [Cu2L(μ2-pz)] (pz = pyrazolate anion) of copper(II) with the condensation product of 1,3-diamino-2-propanol (DAP) and 4-formyl-3-formylcoumarin (H3L) is synthesized and characterized. Magnetic properties of the complex are compared with those demonstrated by a number of previously studied compounds based on bis-azomethine derivatives of DAP with the structure similar to that of studied compounds, i.e. identical exchange fragments and immediate donor environments of copper(II) ions. Antiferromagnetic exchange parameters of these complexes are calculated within the DFT method using the “broken-symmetry” approximation. It is shown for the complexes with the same structure of the exchange fragment and the nearest donor environment of metal centers that the significant variation of the exchange parameter (∼100 cm−1) is determined by the electronic nature of non-bridging donor oxygen atoms of the carbonyl fragment of the bis-azomethine ligand.

Published
2019
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15. Crystal structure of the (N,N′-bis[chromen-2,4-dione]-3-{2′-hydroxypropylenediamine-N,N′,O,O′}) (dimethylsulfoxide)copper(II) complex

Author

Igor N. Shcherbakov, Valery G. Vlasenko, G. G. Aleksandrov, Sergey I. Levchenkov, and Leonid D. Popov

Subjects
chemistry.chemical_classification, Base (chemistry), 010405 organic chemistry, Ligand, chemistry.chemical_element, Crystal structure, 010402 general chemistry, 01 natural sciences, Nitrogen, Copper, 0104 chemical sciences, Inorganic Chemistry, Crystal, Crystallography, chemistry, Square pyramid, Materials Chemistry, Molecule, Physical and Theoretical Chemistry
Abstract

The N,N′-bis[chromen-2,4-dione]-3-{2′-hydroxypropylenediamine-N,N′,O,O′}copper(II) solvate complex with dimethylsulfoxide is synthesized. The crystal and molecular structure of the complex is determined by X-ray diffraction. The coordination polyhedron of the copper atom is a square pyramid with the base formed by two oxygen atoms and two nitrogen atoms of the ligand and a vertex consisting of the oxygen atom of the coordinated DMSO molecule.

Published
2017
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16. Local atomic structure of mono- and binuclear metal complexes based on 3-formylpyrone and 3-formylcoumarin bis-azomethines

Author

Alexander L. Trigub, Leonid D. Popov, Sergey I. Levchenkov, Vladimir V. Lukov, Ya. V. Zubavichus, Igor N. Shcherbakov, Valery G. Vlasenko, and I. V. Pankov

Subjects
chemistry.chemical_classification, Denticity, Extended X-ray absorption fine structure, Chemistry, Ligand, Bridging ligand, 010402 general chemistry, 010403 inorganic & nuclear chemistry, 01 natural sciences, XANES, Pyrone, 0104 chemical sciences, Coordination complex, Inorganic Chemistry, Metal, chemistry.chemical_compound, Crystallography, visual_art, Materials Chemistry, visual_art.visual_art_medium, Physical and Theoretical Chemistry
Abstract

A series of Cu, Ni, and Mn complexes based on formylpyrone and formylcoumarin azomethynes with 1,3- diaminepropanol-2. The analysis of XANES and EXAFS spectra of the Cu, Ni, and Mn complexes, which were processed by both Fourier and wavelet transforms, enables the determination of local atomic structural parameters and the unambiguous evidence of the formation of both dinuclear and mononuclear structures of these coordination compounds. The possibility of forming binuclear compounds is shown to depend mainly on the nature of the bridging ligand and be independent of the type of the polydentate azomethyne ligand: pyrone or coumarin. The obtained structural results are well consistent with the magnetochemical data for the complexes.

Published
2017
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46. Crystal structure of a trinuclear complex of zinc(II) with 2,6-Di- tert-butyl- p-quinone 1′-phthalazinylhydrazone.

Author

Gol'dberg, A., Kiskin, M., Popov, L., Levchenkov, S., Shcherbakov, I., Tupolova, Yu., and Kogan, V.

Subjects
ZINC compounds, CRYSTAL structure, COMPLEX compounds, HYDRAZONES, QUINONE, TAUTOMERISM, X-ray crystallography, PHTHALAZINE
Abstract

2,6-Di- tert-butyl- p-quinone 1′-phthalazynylhydrazone (HL) is synthesized; the total energies and geometry of the possible hydrazone tautomeric forms are calculated by quantum chemical methods. The hydrazone phthalazone tautomer is shown to be the most stable, which is well consistent with the H NMR spectroscopic data for hydrazone. An X-ray crystallographic analysis is performed of the hydrazone-based Zn(II) trinuclear complex, in which zinc atoms are linked by the diazine bridge of the phthalazine cycle and two pivalate bridges. The geometric properties of the monodeprotonated hydrazone residue in the complex are similar to the calculated data for the phthalazone hydrazone tautomeric form. [ABSTRACT FROM AUTHOR]

Published
2014
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