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1.
The thermodynamic and geometric parameters of the molecular structures of macrotricyclic Tc(II), Ru(II), Rh(II), Pd(II), Ag(II), and Cd(II) complexes with the (NSSN)-coordination of the ligand donor sites formed by complexation of the corresponding M(II) ions with ethanedithioamide H2N–C(=S)–C(=S)–NH2 and ethanedial HC(=O)–CH(=O) have been calculated by the OPBE/TZVPQZP hybrid density functional theory method with the use of the Gaussian09 program package. The bond lengths and bond angles in these complexes have been reported, and it has been stated that the Rh(II) and Ag(II) complexes are nearly planar, the Tc(II), Pd(II), and Cd(II) complexes are slightly nonplanar, while the Ru(II) complex exhibits a rather considerable deviation from coplanarity. The additional five-membered chelate ring resulting from template cross-linking is either strictly planar (in the Tc(II), Rh(II), Pd(II), and Ag(II) complexes) or nearly planar (in the Ru(II) and Cd(II) complexes). 相似文献
2.
The luminescent properties of a d 0 metal complex in binary aprotic media in which preferential solvation can occur were studied at room temperature. It was shown that the luminescence quantum yield for the complex in liquid solutions is sensitive to changes in the multilayer solvation shell. 相似文献
3.
The geometric parameters of the molecular structures of M(II) (5555)macrotetracyclic complexes with a tetradentate (NNNN) macrocyclic ligand, formed by template reactions in the systems M(II)-ethanedithioamide-ethanedial-1,2-ethenediol systems, as well as of the molecular structure of the template ligand forming the coordination sphere of these complexes, have been calculated by the OPBE/TZVP density functional theory method. The bond lengths and bond and torsion angles in the complexes, as well as the standard enthalpies, entropies, and Gibbs energies for each of them, are reported. 相似文献
4.
The adsorption of Cl−, Br−, and I− ions from their 0.1 M solutions in dimethyl formamide at renewable liquid Hg- and Ga-electrodes was studied under similar
experimental conditions by the differential-capacitance and jet-electrode methods. The data obtained points out to a strong
effect of the metal nature on adsorption parameters and the halogenide-ion surface activity series. The halogenide-ion surface
activity at the Hg-electrode increased in the following sequence: Cl− < Br− < I−; at the Ga-electrode, in the reverse sequence: I− < Br− < Cl−. The results are explained qualitatively in terms of the Andersen-Bockris model. It follows from the obtained data that (1)
the free energy of the metal-halogenide-ion interaction increases in the following sequence: I− < Br− < Cl−; (2) the free energy of the Ga-halogenide-ion interaction exceeds that of the Hg−halogenide-ion interaction; and (3) the difference of the Cl−, Br−, and I− ions interaction with the metals increased significantly when passing from Hg− to Ga-electrode. 相似文献
5.
The adsorption of Cl−, Br−, and I− ions on the renewable liquid In-Ga and Tl-Ga electrodes from 0.1 M solutions in dimethyl formamide (DMF) is investigated
by using the method of differential capacitance measurements. The results are compared with similar data obtained on Hg and
Ga electrodes in DMF and with the corresponding data obtained in acetonitrile (AN). It is shown that, in DMF, the adsorption
parameters and the series of surface activity of halide ions (Hal−) significantly depend on the metal nature. In contrast to Hg electrode, on which the surface activity of halide ions increases
in the series: Cl− < Br− < I−, on In-Ga, as well as on the Ga electrode, it varies in the reverse order: I− < Br− < Cl−, whereas on the Tl-Ga electrode, partially reversed series of surface activity is observed: Br− < I− < Cl−. The results are explained within the framework of Andersen-Bockris model. An analysis of experimental results leads to the
following qualitative conclusions: (1) on the In-Ga and Tl-Ga electrodes, as well as on Ga electrode, free energy of metal-Hal− interaction (
$
\Delta G_{_{M - Hal^ - } }
$
\Delta G_{_{M - Hal^ - } }
) increases in series I− < Br− < Cl−; (2) for Cl−, Br−, and I−,
$
\Delta G_{_{M - Hal^ - } }
$
\Delta G_{_{M - Hal^ - } }
) grows in series Tl-Ga < In-Ga < Ga; (3) an absolute magnitude of $
\Delta G_{_{M - Hal_1^ - } } - \Delta G_{_{M - Hal_2^ - } }
$
\Delta G_{_{M - Hal_1^ - } } - \Delta G_{_{M - Hal_2^ - } }
(Hal1−, and Hal2− are any ions of Cl−, Br−, and I−) increases in series Hg < Tl-Ga < In-Ga < Ga; (4) the metal-DMF chemisorption interaction is much stronger than the metal-AN
interaction and increases in series Tl-Ga < In-Ga < Ga. 相似文献
6.
\( {\text{CN}} (B^{2}\Sigma ^{ + } \to X^{2}\Sigma ^{ + } ) \) violet system was investigated using optical emission spectroscopy in a non-equilibrium microwave atmospheric-pressure plasma jet in argon expanding in air. From the analysis of the emission spectra of the discharge in the range of 380 and 400 nm, the violet system of CN was found to be overlapped with the \( {\text{N}}_{2}^{ + } \left( {B^{2}\Sigma _{u}^{ + } , v = 1 \to X^{2}\Sigma _{g}^{ + } , v = 1} \right) \) and \( {\text{N}}_{2} \left( {C^{3}\Pi _{u} \to B^{3}\Pi _{g} } \right) \) bands, sequence \( \Delta \upsilon = - \;3 \). A numerical disentangle technique, developed in this work, permitted to obtain a well resolved violet system from the different systems observed, namely the nitrogen First Negative and the Second Positive systems. The \( {\text{CN}} (B^{2}\Sigma ^{ + } \to X^{2}\Sigma ^{ + } ) \) band head intensity was determined and analysed as function of discharge powers between 30 and 150 W and fluxes between 2.5 and 10.0 slm. With aid of this numerical approach it was also possible to obtain the rotational temperature, from (1600 ± 100) to (2300 ± 100) K and vibrational temperature between (9000 ± 800) and (14,000 ± 800) K along the plasma jet. The kinetics of \( {\text{CN}} (B^{2}\Sigma ^{ + } ) \) state was analysed as well. 相似文献
7.
Xiudan Song Shuxia Li Zishi Jiang Yongzhi Zhang 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(9):1752-1760
The binding energy of Cu2+(H2O) is computed to be 98.4 kcal/mol and thus one-photon photodissociation is not possible in the 3400–3800 cm–1 (9.7–10.9 kcal/mol) region. To study whether the infrared photodissociation processes of Cu2+(H2O) can occur by multiple argon atoms tagging technique, density functional and CCSD(T) methods are used to investigate the geometries, OH stretching frequencies and the argon atom binding energies of Cu2+(H2O)Ar n (n = 1–4) complexes. Various isomers are found resulting from the different coordination sites of argon atoms. The OH stretches in these complexes are shifted to lower frequencies than those of the free water molecule, and the corresponding vibrational red shifts are progressively smaller as more argon atom is added to Cu2+ while binding an argon atom to an OH site should lead to additional sizable red shift to the OH stretching vibrations. 相似文献
8.
Analytical relations through the initial values are derived for the molecular auxiliary functions A
α (x) and B
n
(x), where α =n+ɛ, 0⩽ ɛ < 1 and n=0,1,2,.... These relations are useful in the fast calculation of multicenter molecular integrals over integer and noninteger n Slater type orbitals. It is shown that the formulas obtained are numerically stable for all values of n,ɛ and x.PACS No: 31.15.+q, 31.20.EjAMS subject classification: 81-V55, 81-V45 相似文献
9.
The geometric parameters of the molecular structures and thermodynamic parameters of macrotricyclic M(II) (M = Mn, Fe, Co, Ni, Cu, Zn) complexes with an MN2S2 chelate core formed by the template reactions of the M(II) with N-methylthiocarbohydrazide H3C–HN–HN–C(=S)–NH–NH2 and hexanedione- 2,5 H3C–C(=O)–CH2–CH2–C(=O)–CH3 have been calculated by the DFT method with the Gaussian09 program package. The bond lengths, bond angles, and some nonbonded angles in these complexes have been determined. In all the complexes, the M(II) central ion is pseudotetrahedrally coordinated by the donor atoms of an inner-sphere tetradentate ligand; the (N2S2) group of the donor atoms is not planar. The additional seven-membered chelate rings show significant deviations from coplanarity (>60°). The noncoplanatiry of the five-membered rings is less pronounced. 相似文献
10.
A. N. Chekhlov 《Russian Journal of Coordination Chemistry》2005,31(3):166-169
The crystal and molecular structures of (trans-3,4-diamino-2,2,6,6-tetramethylpiperidine-1-oxyl-N3, N4)(oxalato-O,O)platinum(II) (C11H20N3O5Pt) are studied by X-ray diffraction analysis. The crystals are monoclinic: a=15.210 , b=7.222 , c=14.520 , =118.14°, Z=4, and space group P21/c. The structure is solved by the direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R=0.05 against 3227 independent reflections (CAD4 automated diffractometer, MoK
). A molecule of the complex is mononuclear with two different bidentate ligands. The coordination of the Pt2+ cation is a distorted square. The crystal contains intermolecular hydrogen bonds.Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 3, 2005, pp. 179–182.Original Russian Text Copyright © 2005 by Chekhlov.This revised version was published online in April 2005 with a corrected cover date.This revised version was published online in April 2005 with a corrected cover date. 相似文献
11.
M. Kuzmanović V. Bojović J. Savović A. Antić-Jovanović 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(9):1515-1519
Relative intensities of eight vibronic bands, belonging to the Δυ = −2 sequence of the B
2Σ+ −X
2Σ+ electronic transition of four GaO isotopomers have been measured and interpreted in terms of possible isotope effects on
the parameters governing the band intensity. Obtained results showed very small isotope effect on the Franck-Condon factors
and r-centroids and revealed that the observed intensity ratios of the corresponding isotope bands are controlled mainly by the
isotope abundance of 69Ga and 71Ga in natural gallium.
The article is published in the original. 相似文献
12.
It has been found that halide ions (Cl–, Br–, and I–) in aqueous solution initiate structural transformation of silver trigonal prisms (20?50 nm in size) in the sequence prism ? disc ? sphere. It has been demonstrated that the change in structure is caused by the formation of poorly soluble silver salts on nanoprisms and occurs by the electrochemical mechanism. The efficiency of the process is dictated by the nature of the halide ion. 相似文献
13.
N. Begović Z. Marković S. Anić 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(13):2283-2287
The kinetics of gas reaction \(HOCl\underset{{k_r }}{\overset{{k_f }}{\longleftrightarrow}}H(^2 S) + OCl(X^2 \Pi _i )\) was analyzed by the MP4 method. In the temperature range of 100–373 K the rate constants k f and k r and equilibrium constant K were changed from 1.10 × 10?220 to 1.17 × 10?52 s?1, from 2.89 × 10?16 to 1.68 × 10?5s?1 and from 3.80 × 10?205 to 6.96 × 10?48 respectively. In the above temperature range, the activation energy of the forward reaction (E f) is 105.05 kcal/mol. In the same temperature interval there are two kinetic domains for the reverse reaction with activation energies (E r1 = 5.53 kcal/mol when T is 100–273 K and E r2 = 14.50 kcal/mol when T is 273–373 K, respectively. 相似文献
14.
M. M. El’chaninov A. A. Aleksandrov I. M. El’chaninov 《Russian Journal of Organic Chemistry》2015,51(12):1762-1765
2-(2-Furyl)-1,7-dimethyl-1H,7H-benzo[1,2-d: 3,4-d′]diimidazole was synthesized by the Weidenhagen reaction followed by N-methylation. Electrophilic substitution reactions of the title compound (nitration, bromination, sulfonation, formylation, and acylation) involved both the furan ring and central benzene fragment. 相似文献
15.
A. S. Gordetsov S. V. Zimina S. V. Saprykina L. B. Loginova A. V. Piskunov V. F. Ur’yash E. M. Moseeva 《Russian Journal of General Chemistry》2011,81(4):658-662
1,3,5-Tris[bis(η5-cyclopentadienyl)chlorovanadium]melamin is prepared in high yield by the reaction of N,N′-bis(trimethylsilyl)dicyandiamide with bis(η5-cyclopentadienylvanadium) dichloride in tetrahydrofuran. As side products, trimethylchlorosilane and cyclopentadiene formed.
Reaction of N,N′-bis(trimethylsilyl) dicyandiamide with benzoyl chloride results in the formation of tris(benzoyl)melamin. 相似文献
16.
Zach D. Reed Michael A. Duncan 《Journal of the American Society for Mass Spectrometry》2010,21(5):739-749
Manganese carbonyl cations of the form Mn(CO)
n
+ (n = 1−9) are produced in a molecular beam by laser vaporization in a pulsed nozzle source. Mass selected infrared photodissociation
spectroscopy in the carbonyl stretching region is used to study these complexes and their “argon-tagged” analogues. The geometries
and electronic states of these complexes are determined by comparing their infrared spectra to theoretical predictions. Mn(CO)6+ has a completed coordination sphere, consistent with its predicted 18-electron stability. It has an octahedral structure
in its singlet ground state, similar to its isoelectronic analogue Cr(CO)6. Charge-induced reduction in π back-bonding leads to a decreased red-shift in Mn(CO)6+ (υCO = 2106 cm−1) compared with Cr(CO)6 (υCO = 2003 cm−1). The spin multiplicity of Mn+(CO)
n
complexes gradually decreases with progressive ligand addition. MnCO+ is observed as both a quintet and a septet, Mn(CO)2+ is observed only as a quintet, while Mn(CO)3,4+ are both observed as triplets. Mn(CO)5+ and Mn(CO)6+ are both singlets, as are all larger complexes. 相似文献
17.
M. S. Kozlova A. V. Markin V. N. Larina L. G. Domracheva M. S. Sheiman N. V. Karyakin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2008,82(12):1993-1998
The temperature dependence of the heat capacity of crystalline bis-(η5-cyclopentadienylirondicarbonyl) was studied over the temperature range 5–495 K in precision adiabatic vacuum and differential scanning calorimeters. The temperature dependence contained an anomaly (160–295 K) with a maximum at 250 K interpreted as a λ transition in the solid state. The fusion of the sample occurred at 435–491 K; it was accompanied by partial substance decomposition. The thermodynamic functions of crystalline bis-(η5-cyclopentadienylirondicarbonyl) were calculated from T→0 to 472.9 K. The enthalpy of combustion of the compound was determined in an isothermal calorimeter with a stationary bomb. The standard thermodynamic functions of its formation in the crystalline state at 298.15 K were calculated. 相似文献
18.
Yilin Zhao Katharina Boguslawski Paweł Tecmer Corinne Duperrouzel Gergely Barcza Örs Legeza Paul W. Ayers 《Theoretical chemistry accounts》2015,134(10):120
The bonding mechanism of ethene to a nickel or palladium center is studied by the density matrix renormalization group algorithm, the complete active space self-consistent field method, coupled cluster theory, and density functional theory. Specifically, we focus on the interaction between the metal atom and bis-ethene ligands in perpendicular and parallel orientations. The bonding situation in these structural isomers is further scrutinized using energy decomposition analysis and quantum information theory. Our study highlights the fact that when two ethene ligands are oriented perpendicular to each other, the complex is stabilized by the metal-to-ligand double-back-bonding mechanism. Moreover, we demonstrate that nickel–ethene complexes feature a stronger and more covalent interaction between the ligands and the metal center than palladium–ethene compounds with similar coordination spheres. 相似文献
19.
Fillipe V. Rocha Carolina V. Barra Silmar J. S. Franchi Adelino V. G. Netto Antonio E. Mauro Regina C. G. Frem 《Journal of Thermal Analysis and Calorimetry》2011,106(2):385-389
Four new mononuclear Pd(II) complexes of the type [PdX2(tdmPz)] {X = Cl− (1); Br− (2); I− (3); SCN− (4); tdmPz = 1-thiocarbamoyl-3,5-dimethylpyrazole} have been synthesized and characterized by elemental analysis, IR spectroscopy,
1H and 13C{1H}-NMR experiments. The thermal behavior of the complexes 1–4 has been investigated by means of thermogravimetry (TG) and differential thermal analysis (DTA). From the initial decomposition
temperatures, the thermal stability of the complexes can be ordered in the sequence: 3 < 4 ≡ 2 < 1. The final products of the thermal decompositions were characterized as metallic palladium by X-ray powder diffraction. 相似文献
20.
The orbital nature of excited states of organometallic π-complexes of early transition metals of the third-fifth periods with the d 0 electronic configuration was surveyed, and their photophysical characteristics were discussed. Examples of long-lived luminescence generated by ligand-to-metal charge transfer in liquid solutions at room temperature were thoroughly considered. Regularities of nonradiative triplet-triplet energy transfer from aromatic molecules and d 0 metallocene complexes of Group 4B transition metals to unsaturated hydrocarbons were examined. 相似文献