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1.
The effects of a substrate additive, H+ and solvents (water and acetone), on the micelle-catalyzed aquation of tris-(4,7-diphenyl-1, 10-phenanthroline)iron(II),
Fe(Ph2Phen)3
2+, have been investigated using#Triton X-100 micelles. The k0
vs. [TX-100] profiles at fixed [H2O] are structured, exhibiting maxima. Catalytic factors of 46.6–171.7 are observed for 5.56×10−2≤[H2O] 55.60×10−2 mol dm−3. On the other hand, at fixed [H+], the k0
vs. [TX-100] exhibit broad maxima. The aquation reaction is inhibited by H+ and catalytic factors decrease rapidly and exponentially from 422.5 to 20.9 for 0.20×10−3≤[H+]≤2.00×10−3 mol dm−3. The aquation is found to be faster (ca. 160–1200 fold) in acetone than in the aqueous medium depending on the added [H2O]. These observations are rationalized on the basis of a proposed modified lamellar structure for the Triton X-100 (TX-100)
micelles in which direct substitution of water molecules into the coordination sphere of the complex occurs. 相似文献
2.
3.
Fe(phen)
3
2+
oxidation by bromate has been investigated at large excesses of bromate. The kinetics are consistent with the mechanism suggested earlier for the similar reaction of Ce3+ oxidation.
Fe(phen) 3 2+ . , , Ce3+ .相似文献
4.
The aquation of tris(1, 10-phenanthroline) iron(II) has been studied in aqueous polyacrylamide solutions. The rate increases up to 2.8 times at low polymer concentrations, and subsequently decreases. These effects are attributed to changes in the local water activity in the region of the complex.
(1, 10-) (II) . 2,8 , . .相似文献
5.
Sunil Desai C. S. Feigerle John C. Miller 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,26(Z1):183-185
Supersonic jet expansions of mixtures of nitric oxide with either nitrous oxide or carbon dioxide have been investigated over a wide range of relative concentrations. Mixed molecular cluster ions of the form (NO)
m
+
(N2O)n and (NO)
m
+
(CO2)n are detected following non-resonant two-photon ionization. Over a wide range of intermediate concentrations, the cluster ion distributions (NO)
3
+
(N2O)n and (NO)
3
+
(CO2)n with n30 are significantly more intense than clusters containing other numbers of nitric oxide molecules. The extra abundance of these species is attributed to their especially stable structures and several possible forms are discussed. An intriguing possibility involves a stable cyclic nitric oxide trimer (or ion) when combined with nitrous oxide or carbon dioxide clusters. 相似文献
6.
The polarographic behaviour of tetra-n-butylammonium hexacyanoferrate(II) has been studied in N-methylpyrrolidinone, N,N-dimethylformamide, acetonitrile, dimethylsulphoxide, N,N-dimethylthioformamide, 1,2-dichloroethane, propanediolcarbonate, nitromethane, ethanol, methanol and acetic acid using tetrabutylammonium perchlorate as supporting electrolyte. A polarographically reversible electrode process was found in all solvents but acetic acid. The large shift in half-wave potentials (vs. bisbiphenylchromium(I) as a reference ion) is interpreted on the basis of donor-acceptor interactions between the hexacyanoferrate ions and solvent molecules and also between the hexacyanoferrate ions and cations of the supporting electrolyte. The considerable difference in half-wave potentials between tetraethylammonium and tetrabutylammonium perchlorate is discussed within the framework of this concept. 相似文献
7.
The geometrical parameters, normal vibration frequencies, and thermochemical characteristics of the Na2Cl+, NaCl
2
−
, Na3Cl
2
+
, and Na2Cl
3
−
ions in saturated vapors over sodium chloride were calculated by the ab initio methods including electron correlation. According to calculations, the Na2Cl+ and NaCl
2
−
triatomic ions have a linear equilibrium D
∞h
configuration. The pentaatomic ions can exist in the form of the D
∞h
linear isomer, C
2v
planar cyclic isomer, or D
3h
bipyramidal isomer. At ∼1000 K the Na3Cl
2
+
and Na2Cl
3
−
ions exist predominantly in the form of the linear isomers. The energies and enthalpies of the ion-molecule reactions involving
the above ions were calculated. The formation enthalpy of the ions Δf
H
0(0 K) was determined: 230 ± 2 kJ/mol (Na2Cl+), −96 ± 4 kJ/mol (Na2Cl
3
−
), −616 ± 2 kJ/mol (NaCl
2
−
), and −935 ± 4 kJ/mol (Na2Cl
3
−
).
Original Russian Text Copyright ? 2007 by T. P. Pogrebnaya, A. M. Pogrebnoi, and L. S. Kudin
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 48, No. 6, pp. 1053–1061, November–December, 2007. 相似文献
8.
Results are presented for two experiments on N2O2+ cluster ions formed via the reactions O2+ + N2 + M → (N2) (O2+) + M (i), and NO+ + NO + M → (NO)2+ + M (ii). In the first experiment the N2O2+ clusters are collisionally dissociated. The resulting collision-induced dissociation (CID) spectra show almost exclusively O2+ and N2+ products from N2 O2+ formed via the first reaction, and almost exclusively NO+ products from N2O2+ formed via the second reaction. In the second experiment, single-photon photodissociation of N2O2+ ions produced by both reactions (i) and (ii) was investigate using 514.5 and 634 nm radiation. The results indicate that the N2O2+ cluster from reaction (i) cannot be photodissociated while the N2O2+ cluster from reaction (ii) undergoes photodissociation at both wavelengths. These experiments indicate that two distinct N2O2+ cluster ions exist and that reactions (i) and (ii) selectively produce the two ions. 相似文献
9.
The rate of the hexacyanoferrate redox system shows a first order dependence on the concentration of the cationic component of the supporting electrolyte. The catalytic influence of the alkali metal cations on the electrode process increases in the order Li+<Na+<K+~Cs+. The temperature dependence of the rate constant of the electrode process in KF and LiNO3 has been measured and the results show that the activated complex is formed by the collision or association of a cation of the supporting electrolyte with the reactant anion, which may already be paired with one cation. It is suggested that this mechanism may be applicable to other electrode reactions involving highly charged species. 相似文献
10.
11.
Polymeric pendant Ru(bpy)_3~(2+) complexes were prepared from homopolymer and copolymers of 4-methyl-4'-vinyl-2,2'-bipyridine (Vbpy). Vbpy was prepared from 4-methylpyridine. The comonomers were styrene (St), acrylic acid (AA), N-vinylpyrrolidone (Pyr), 4-vinylpyridine (Vpy), methyl methacrylate (MMA), 2-hydroxyethyl methacrylate (HEMA), acrylonitrile (AN) and N-ethyl-4-vinylpyridium bromide (EQ-Vpy). The fraction of the pendant Ru(bpy)_3~(2+) repeating unit in the polymeric complex was 0.022 to 0.052. Absorption maximum, molar extinction coefficient, emission maximum and relative emission intensity of the polymeric complexes were studied. 相似文献
12.
Jean-Jacques Brunet Remi Chauvin Ousmane Diallo Bruno Donnadieu Joëlle Jaffart Denis Neibecker 《Journal of organometallic chemistry》1998,570(2):9166
KHFe(CO)4 reacts with tris(amino)phosphines by substitution at phosphorus leading to [bis(amino)phosphine]tetracarbonyliron complexes [(R1R2N)2PH]Fe(CO)4. The X-ray structure has been determined for R1=R2=Ph. Deprotonation of these complexes with KH affords stable potassium phosphidotetracarbonylferrates which can be alkylated or acylated at phosphorus. 相似文献
13.
14.
15.
The redox properties of the system Fe(tmphen)3(II/III) (tmphen=3,4,7,8-tetramethyl-1,10-phenanthroline) have been studied in the solvents nitromethane, acetonitrile, propanediol-1,2-carbonate, dimethylformamide, dimethylacetamide, dimethylsulfoxide and of the systems Fe(phen)3(II/III) (phen=1,10-phenanthroline) and Fe(niphen)3(II/III) (niphen=5-nitro-1,10-phenanthroline) in the solvents nitromethane, acetonitrile, propanediol-1,2-carbonate and acetone. The redox potentials of Fe(tmphen)3(II/III) are nearly independent of the solvent suggesting that the system might be used as a reference redox couple similar to the systems ferrocene/ferricinium or bisbiphenylchromium(0/I). In contrast the redox potentials of Fe(niphen)3(II/III) show a significant decrease with increasing donor number of the solvent which can be explained by nucleophilic attack of solvent molecules at the iron. It is shown that such a mechanism is consistent with the known solvent and salt effects on the kinetics of dissociation of ferroin and ferriin type complexes. 相似文献
16.
V. A. Antipin G. S. Parshin V. P. Kazakov S. N. Zagidullin 《Reaction Kinetics and Catalysis Letters》1985,27(1):103-107
Quasi-harmonic oscillations of chemiluminescence intensity at certain concentrations of the components for the (S–Cr2O
7
2–
–UO
2
2+
) system in concentrated sulfuric acid and chemiluminescence and dark stages with the participation of intermediates Cr(V), U(IV) and sulfur peroxide radicals (HS2O6
.) have been discovered. Chemiluminescence is attributed to the interaction of HS2O6
. compounds. The processes of deactivation of the excited states of uranyl involve the participation of Cr(V). A scheme for the oscillation chemiluminescence reactions is suggested.
(S–Cr2O 7 2– –UO 2 2+ ) H2SO4 , . Cr(V), U(IV) (HS2O6 .) HS2O6 . Cr(V) . .相似文献
17.
The photodissociation cross section of the weakly bound positive ion cluster O2+(H2O) has been measured at 15 discrete energies between 1.833 and 2.727 eV. Measurements indicate the cross section increases smoothly from 0.6 to 6 × 10-18 cm2 over this energy range. These cross section values are the largest reported for a positive ion cluster of atmospheric importance. 相似文献
18.
L. N. Mazalov S. V. Trubina I. M. Oglezneva N. A. Kryuchkova O. V. Tarasenko V. L. Varand T. E. Kokina S. V. Larionov 《Journal of Structural Chemistry》2005,46(3):542-545
X-ray photoelectron and voltammetry studies of the charged state of the metal atom in nickel(II) chelate complexes with ligands
containing CS
2
−
and PS
2
−
groups and in heteroligand complexes on their basis were carried out. It is shown that the degree of formal oxidation of
the nickel atom in the complexes corresponds to Ni(II). In the case of heteroligand complexes, addition of nitrogen heterocycles
causes an increase in the electron density on the atoms of the coordination center. Theoretical data obtained in ab initio quantum chemical model calculations correlate with the experimental results.
Original Russian Text Copyright ? 2005 by L. N. Mazalov, S. V. Trubina, I. M. Oglezneva, N. A. Kryuchkova, O. V. Tarasenko,
V. L. Varand, T. E. Kokina, and S. V. Larionov
__________
Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 3, pp. 554–557, May–June, 2005. 相似文献
19.
B. V. Mill 《Russian Journal of Inorganic Chemistry》2009,54(9):1355-1357
Compounds A3+Te6+M33+X25+O14 (A = Na, K; M = Ga, Al, Fe; X = P, As, V) with the Ca3Ga2Ge4O14 structure (sp. gr. P321) were prepared by solid-phase synthesis at 600–850°C in air. The compounds melt incongruently or decompose in the solid
state. 相似文献
20.
Ab initio Molecular orbital calculations with large basis sets and incorporating correlation are used to examine the structures and relative energies of the vinyloxonium (CH2CHOH2+) and 1-hydroxyethyl (CH3CHOH+) cations. The best structure of the vinyloxonium ion has the OH2 plane perpendicular to the CCO plane. The energy difference between the vinyloxonium and 1-hydroxyethyl cations is predicted to be 92 kJ mol?1, substantially greater than a recent experimental estimate of 41 ± 12 kJ mol?1 相似文献