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Pt(II) and Pd(II) dichloride complexes with 5,7-ditertbutyl-1,2,4-triazolo[1,5-a]pyrimidine (dbtp) have been synthesized and characterized by infrared and 1H, 13C NMR, 13C CPMAS spectroscopy. The structures of the cis-PtCl2(dbtp)2 · EtOH (1) and cis-PdCl2(dbtp)(dmso) (2) has been determined by signal-crystal X-ray diffraction. In both complexes the X-ray crystal structures shows that heterocycle ligand (dbtp) binds the central atom monodentate via nitrogen atom N(3). In addition, compound (2) is interesting for its structural features, because it is the first report of mixed dichloride Pd(II) complexes with N-donor (triazolopyrimidine) and S-donor (dimethylsulfoxide) ligands. In this structure the Pd–Cl distances are: 2.302(1) and 2.281(1) Å, Pd–N 2.041(3) Å and Pd–S 2.245(1) Å. The 1H, 13C NMR studies show clearly that these structures are retained in solution. 相似文献
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The magnetization fluctuations are considered in thin films treated as a set of monoatomic layers parallel to the film surfaces. The correlation functions have been determined and their forms are discussed. The influence of inhomogeneity of magnetization on the equation of state for a magnetic system described by Valenta's model is studied. The behaviour of the spontaneous magnetization as well as the magnetic susceptibility near the Curie point is described.This work is partially supported by the Institute of Physics of the P.A.S. 相似文献
6.
The ferromagnetic resonance phenomenon is considered in one-dimensional magnets in which the envelope solitions can appear. The existence of solitons influences the ferromagnetic resonance spectrum and therefore the resonance technique seems to be a possible tool in order to identify the existence of solitons and their properties. 相似文献
7.
L. Wojtczak S. Romanowski W. Stasiak B. Mrygoń 《Czechoslovak Journal of Physics》1981,31(9):1024-1036
The density of electronic states and its spatial distribution in thin films are considered including the electron correlations in the coherent phase approximation applied to the intra-atomic interaction. This new approach allows us to derive the line shape for electronic levels which is important from the point of view of the convergency for the density function in the case of systems with restricted dimensions. Detailed calculations are performed for 4s copper film functions with the fcc lattice and various crystallographic orientations of the surfaces.The authors are very grateful to Professor L. Valenta (Prague) for his kind interest in this paper and to Dr. J. Mizia (Cracow) for helpful discussions. We would like to express our gratitude to Professor M. Wonicki and Mrs M. Firszt (Toru) for their help in obtaining the computer program procedure for two-particle interaction integrals calculations.The paper has been done in the framework of the Problem M.R I-11. 相似文献
8.
Grzegorz Wrzeszcz Andrzej Wojtczak Magdalena Zawadzka 《Central European Journal of Chemistry》2014,12(6):652-658
A new heterometallic compound, [CoCl(NH3)5][KCr(C2O4)3]·0.5H2O (1), has been synthesized and characterized by elemental analysis, IR and electronic spectra, thermal analysis, variable temperature magnetic susceptibility measurements, and single crystal X-ray diffraction. Compound 1 consists of two-dimensional [{KCr(C2O4)3}n]2n? layers, [CoCl(NH3)5]2+ ions and water molecules. Within the 2-D layer, three different types of oxalate coordination modes are present. Each K cation is coordinated by eight oxygen atoms from oxalate groups and also weakly interacts with the ninth oxygen atom. The extensive network of hydrogen bond is formed between the [KCr(C2O4)3]2? layer and the [CoCl(NH3)5]2+ ions. These interactions involve all hydrogen atoms of ammonia ligads and water molecule. 相似文献
9.
Oxo/hydoxo zirconium(IV) complex of the general formula [Zr6(μ3-O)4(μ3-OH)4(OOCCH2tBu)9(μ2-OH)3]2 has been isolated, when Zr(OiPr)4 reacted with a 2-fold excess of 3,3-dimethylbutyric acid. Single crystal X-ray diffraction data, collected at 103 and 153 K, showed that the studied compound crystallizes in hexagonal system (P63/m (no. 176)). Structure consists of dimers composed of [Zr6(μ3-O)4(μ3-OH)4(OOCCH2tBu)9] sub-units, linked by six μ2-OH bridges. Infrared spectroscopic studies proved the presence of hydroxo groups in the structure of studied clusters and formation of different types of oxo/hydroxo bridges. The application of variable temperature infrared spectroscopy and differential scanning calorimetry revealed that the structure of this complex undergoes the phase transitions at 143–183 and 203–293 K. Comparison of spectral and crystallographic data suggests that these phase transitions might be related to changes in the strength of Zr–O bonds of μ2-OH bridges linking complex sub-units, and change in symmetry of the crystal lattice (from hexagonal to trigonal). Analysis of thermogravimetric data showed that decomposition of [Zr6(μ3-O)4(μ3-OH)4(OOCCH2tBu)9(μ2-OH)3]2 proceeds with complete conversion to ZrO2 (monoclinic form) between 603 and 803 K. 相似文献
10.
Solvent effects on the electron donor acceptor complex properties of ferrocene and tetranitromethane
Summary Spectral investigations in the 350–800 nm range of ferrocene (FcH) and tetranitromethane [C(NO2)4] solutions in cyclohexane and carbon tetrachloride at concentration-constant (FcH) and variable (tetranitromethane) were
made. The electron donor acceptor (EDA) complex of ferrocene and tetranitromethane and its dissociation to the ferricenium
cation (FcH+) were studied as a function of the solvent, the initial C(NO2)4 concentration and reaction time. 相似文献