| 1. |
- Ivanov, Alexander V., et al.
(författare)
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Bis(diethyldithiocarbamato)pyridinezinc(II) and copper(II) clathrates with pyridine: Molecular structure and EPR and high-resolution solid-state (13C, 15N) NMR spectra
- 1998
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Ingår i: Russian journal of coordination chemistry. - 1070-3284 .- 1608-3318. ; 24:9, s. 645-654
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Tidskriftsartikel (refereegranskat)abstract
- EPR, high-resolution solid-state (13C, 15N) NMR, and X-ray diffraction methods were used to study bis(diethyldithiocarbamato)pyridinezinc(II) and copper(II) clathrates with pyridine, M(EdIc)2Py · Py. The structural functionalities of the Py molecules in these clathrates were found to be different: one of them is coordinated to the complexing atom, while the other (solvate) is hydrogen-bonded to the sulfur atom of one of the ligands. The heterocycle of the uncoordinated Py molecule was found to be geometrically distorted. The structures of the copper and zinc coordination polyhedra are close to trigonal-bipyramidal: two sulfur atoms and the nitrogen atom of pyridine form the equatorial plane; another two sulfur atoms occupy axial positions at larger distances. EPR spectra of the magnetically diluted copper(II) clathrate exhibit well-resolved SHFS from the nitrogen atom of Py, owing to the contribution of the dz2 orbital to the ground-state wave function of the unpaired electron. The NMR data suggest that the nitrogen atoms of the Edtc- ligands are magnetically inequivalent and that the 15N chemical shift of the uncoordinated Py molecule changes in an unusual fashion. Signal assignment was carried out for the experimental 13C and 15N NMR spectra
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| 2. |
- Ivanov, Alexander V., et al.
(författare)
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Bis(diethyldithiocarbamato)pyridinezinc(II) and -copper(II) clathrates M(Edtc)2Py·nL (L = CH2Cl2 and CHCl3; n = 1 and 0.5) : Molecular and crystal structures and EPR and high-resolution solid-state (13C, 15N) NMR spectra
- 1999
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Ingår i: Russian journal of coordination chemistry. - 1070-3284 .- 1608-3318. ; 25:8, s. 543-555
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Tidskriftsartikel (refereegranskat)abstract
- X-ray diffraction analysis, EPR, and high-resolution solid-state (13C, 15N) NMR spectroscopy were used to examine structural organization and spectral properties of six bis(diethyldithiocarbamato)pyridine-zinc(II) and copper(II) solvates with dichloromethane and chloroform, M(Edtc)2Py·nL (n = 1 and 0.5). Typical of the clathrate-type structures, the compounds are penetrated by the ordered molecular channels filled with chemically nonbonded chlorohydrocarbon molecules. At the molecular level, the geometry of coordination polyhedra of complexing atoms is intermediate between trigonal bipyramidal and square pyramidal (the contribution of the square-pyramidal component is quantitatively estimated for the zinc clathrate). Accordingly, the ground state of the unpaired electron in the copper(II) compounds is a combination of the dx2-y2 and dz2 orbitals. It is shown that the nonequivalence of the Edtc- ligands in zinc(II) clathrates manifests itself both magnetically and structurally. The chlorine atoms of the solvate dichloromethane molecules, unlike chloroform molecules, are disordered over the two structural positions with different multiplicities. The 13C and 15N NMR signals are assigned to the atomic positions in the resolved molecular structures
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| 3. |
- Ivanov, Alexander V., et al.
(författare)
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Clathrate Formation of Bis(diethyldithiocarbamato)pyridinezinc(II) and Bis(diethyldithiocarbamato)pyridinecopper(II) with Benzene by EPR, High-Resolution Solid-State 13C and 15N NMR, and X-ray Crystallography
- 1998
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Ingår i: Russian Journal of Inorganic Chemistry. - 0036-0236 .- 1531-8613. ; 43:9, s. 1368-1376
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Tidskriftsartikel (refereegranskat)abstract
- The structures of the clathrates of bis(diethyldithiocarbamato)pyridinezinc(H) and-copper(II) with benzene were studied by EPR, high-resolution solid-state 13C and 15N NMR, and X-ray crystallography. The geometry of the coordination polyhedra in the clathrates M(EDtc)2· Py · C6H6is close to trigonal-bipyramidal. Two short M-S bonds and the M-N bond form the equatorial plane, and two long M-S bonds point toward the axial positions. For the magnetically diluted copper(II) clathrate, the hyperfine structure can be observed at low temperatures due to the nitrogen atom of pyridine, which is associated with the contribution of the dz2orbital to the ground-state wave function of the unpaired electron. The 13C and 15N NMR signals were assigned.
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| 4. |
- Ivanov, Alexander V., et al.
(författare)
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Structure, EPR, and 13C and 15N NMR of Clathrates of Bis(diethyldithiocarbamato)pyridinezinc(II) and Bis(diethyldithiocarbamato)pyridinecopper(II) with 1,2-Dichloroethane
- 1999
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Ingår i: Russian Journal of Inorganic Chemistry. - 0036-0236 .- 1531-8613. ; 44:10, s. 1605-1614
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Tidskriftsartikel (refereegranskat)abstract
- The structural organization of the clathrates of bis(diethyldithiocarbamato)pyridinezinc(II) and -copper(II) with 1,2-dichloroethane, M(Edtc)2Py · L, was studied by EPR, high-resolution solid-state 13C and 15N NMR, and X-ray crystallography. The clathrates contain typical molecular channels and cavities, which accommodate chemically unbound dichloroethane molecules. At the molecular level, the geometry of the zinc and copper coordination polyhedra is intermediate between a trigonal bipyramid and a square pyramid. The ground state of the unpaired electron of copper(II) is a result of mixing the dx2-y2 and dz2 orbitals. The Edtc ligands incorporated in the zinc(II) clathrate are somewhat nonequivalent, both magnetically and structurally. The chlorine atoms of the 1,2-dichloroethane molecule are disordered over two structural positions with different occupancies, which may point to the occurrence of several conformations. The 13C and 15N NMR signals were assigned based on combined analysis of available structural and NMR data
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