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1.
Yu. G. Galyametdinov G. I. Ivanova I. V. Ovchinnikov K. Binnemans D. V. Bruce 《Russian Chemical Bulletin》1999,48(2):385-387
Liquid-crystalline cationic complexes of lanthanides with azomethines containing the alkyl sulfate anion as the counterion
were synthesized. The temperatures of existence of the mesophase of the complexes with the alkyl sulfate anion were by 80–100°C
lower than those of similar complexes with the Cl− and NO3
− counterions.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 387–389, February, 1999. 相似文献
2.
The synthesis and anion binding properties of new ruthenium(II) and cobalt(II) phenanthroline complexes, containing two amide
subunits are described. Evidence for anion binding in dimethyl sulfoxide (DMSO) solution was obtained from u.v.–vis titration
experiments. Results indicated that these receptors showed strong affinity for F− and AcO−, and showed weak affinity for OH− and H2PO
4
−
, and showed no affinity for Cl−, Br−, I−. These receptors interacted with various anions examined through hydrogen-bond formation. 相似文献
3.
The phenyl substituted acridine-1,8-dione (AD) dye reacts with (CH3)2*COH radicals with a bimolecular rate constant of 0.6 × 108 dm3 mol−1 s−1 in acidic aqueous-organic mixed solvent system. The transient optical absorption band (λmax = 465 nm, ɛ = 6.8 × 102 dm3 mol−1 cm−1) is assigned to ADH* formed on protonation of the radical anion. In basic solutions, (CH3)2*COH radicals react with a bimolecular rate constant of 4.6 × 108 dm3 mol−1 s−1 and the transient optical absorption band (λmax = 490 nm, ɛ = 10.4 × 103 dm3 mol−1 cm−1) is assigned to radical anion, AD*−, which has a pKa value of 8.0. The reduction potential value of the AD/AD*− couple is estimated to be between −0.99 and −1.15 V vs NHE by pulse radiolysis studies. The cyclic voltammetric studies showed
the peak potential close to −1.2 V vs Ag/AgCl. 相似文献
4.
A series of neutral cyclohexadiamine anion receptors containing nitro, phenanthroline or ruthenium(II) have been designed
and synthesized. Their u.v.–vis spectroscopy investigations reveal that the receptor bearing nitro group displays the strongest
affinities for F−, AcO−, H2PO
4
−
and can be used as an efficient detection tool for the above anions. Results indicate that the anion affinities can be enhanced
through appending nitro group and ruthenium(II) metal compared with phenanthroline moiety. 相似文献
5.
Radiation-chemical transformations of chloride solutions in the presence of iodide additives were studied by pulse radiolysis.
Radical anion Cl2
⋅− oxidize I− ion, while in the secondary reactions Cl2 reacts with I− to form a mixed trihalide ion ICl2
−. A reaction model that satisfactorily describes the experimental data was proposed.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1336–1340, June, 2005. 相似文献
6.
Jos Oomens Jeffrey D. Steill 《Journal of the American Society for Mass Spectrometry》2010,21(5):698-706
We present the first infrared spectra of a mass-selected deprotonated peptide anion (AlaAlaAla) and its decarboxylated fragment
anion formed by collision induced dissociation. Spectra are obtained by IRMPD spectroscopy using an FTICR mass spectrometer
in combination with the free electron laser FELIX. Spectra have been recorded over the 800–1800 cm−1 spectral range and compared with density functional theory calculated spectra at the B3LYP/6-31++G(d,p) level for different
isomeric structures. These experiments suggest a carboxylate anion for [M-H]− and an amide deprotonated (amidate) structure for the a
3 fragment anion [M-H-CO2]−. The frequency for the amidate carbonyl stretch occurring around 1555±5 cm−1 has been confirmed by additional spectroscopic studies of the conjugated base of N-methylacetamide, which serves as a simple
model system for the deprotonated amide linkage in a peptide anion. 相似文献
7.
I. A. Poroshina N. P. Kotsupalo L. T. Menzheres V. P. Isupov 《Journal of Structural Chemistry》1994,35(5):709-719
Crystallochemical features of anion (Cl−, Br−, I−, NO
3
−
, CO
3
2−
, SO
4
2−
) varieties of the aluminum and lithium hydroxide were studied by using the aluminum and lithium binary hydroxide (LiOH·2Al(OH)3·2H2O) model in space group P63cm with the tetrahedral coordination of lithium. Atomic coordinates corresponding to the lowered lattice symmetry were refined.
Institute of Solid State Chemistry and Processing of Mineral Raw Materials, Siberian Branch, Russian Academy of Sciences.
Novosibirsk State Pedagogical University. Translated fromZhurnal Struktumoi Khimii, Vol. 35, No. 5, pp. 158–170, September–October, 1994.
Translated by T. Yudanova 相似文献
8.
A novel dicalix[4]pyrrolyl-substituted 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) dye I with an absorption peak at approximately 670 nm and an emission peak at about 690 nm was prepared. As an anion receptor,
I displayed a red shift in absorption spectra and fluorescence quenching in varying degrees in the presence of F−, AcO−, H2PO4−, or Cl−. Compared with the parent calix[4]pyrrole, a representative anion receptor, I exhibited a stronger affinity to these anions due to the formation of a sandwich complex through multiple hydrogen-bonding
interactions. 相似文献
9.
Erik Rakovsky ?udmila ?úrková Jaromír Marek 《Monatshefte für Chemie / Chemical Monthly》2002,22(2):277-283
Anhydrous 1,6-hexanediammonium dihydrogendecavanadate ((HdaH2)2H2V10O28, 1) was prepared by reaction of V2O5 with 1,6-hexanediamine in aqueous solution. The crystal structure of 1 was determined, and the proton positions in the H2V10O28 4− anion were calculated by the bond length/bond number method. The protons are bound to the centrosymmetrically oriented μ–OV3 groups of the decavanadate anion. Based on the analysis of IR spectra of 1 prepared from H2O and D2O, the absorption band at 871 cm−1 can be attributed to δ(V–Ob–H) vibrations. 相似文献
10.
Fattori Alberto Peter Laurence M. McCall Keri L. Robertson Neil Marken Frank 《Journal of Solid State Electrochemistry》2010,14(10):1929-1936
The electrochemical and spectroelectrochemical properties of the sensitizer dye Z907 (cis-RuLL'(SCN)2 with L=4,4′-dicarboxylic acid-2,2′-bipyridine and L'=4,4′-dinonyl-2,2′-bipyridine) adsorbed on fluorine-doped tin oxide (FTO) and TiO2 surfaces have been investigated. Langmuirian binding constants for FTO and TiO2 are estimated to be 3 × 106 M−1 and 4 × 104 M−1, respectively. The Ru(III/II) redox process is monitored by voltammetry and by spectroelectrochemistry. For Z907 adsorbed
onto FTO, a slow EC-type electrochemical reaction is observed with a chemical rate constant of ca. k = 10−2 s−1 leading to Z907 dye degradation of a fraction of the FTO-adsorbed dye. The Z907 adsorption conditions affect the degradation
process. No significant degradation was observed for TiO2-adsorbed dye. Degradation of the Z907 dye affects the electron hopping conduction at the FTO–TiO2 interface. 相似文献
11.
Mirjana Mladenović Peter Botschwina Peter Sebald Stuart Carter 《Theoretical chemistry accounts》1998,100(1-4):134-146
The results of various ab initio calculations are reported for the electronic ground state of the acetylide anion. An “Eyring's
lake” in the T-shaped configuration is identified with six different methods (SCF, MP2, CCSD, CCSD-T, CCSD(T), and CEPA–1).
The equilibrium bond lengths of HCC− are estimated to be r
e
(CH)=1.0689(3) ? and R
e
(CC)=1.2464(2) ?, and the ground-state rotational constant is predicted to be B
0=41636(20)MHz. The large permanent dipole moment of μ0=−3.093D should facilitate detection of the anion by microwave spectroscopy. The band centers are predicted to be 3211.3cm−1(ν1), 511.1cm−1(ν2), and 1805.0cm−1(ν3). A large transition dipole moment of 0.477 D is calculated for the ν2 band. Rovibrational levels of HCC− up to approximately 20 000 cm−1 above equilibrium are calculated with DVR-DGB and FBR methods on the basis of a previous CEPA–1 potential energy surface.
Different energy patterns are found and discussed, for which anharmonic and Coriolis resonances are shown to play an important
role.
Received: 27 July 1998 Accepted: 12 August 1998 / Published online: 19 October 1998 相似文献
12.
The structure and vibrational frequencies of an aromatic lithium sulfonyl imide, i.e., lithium bis(4-nitrophenylsulfonyl)imide
(LiNPSI) has been studied using self-consistent ab initio Hartree–Fock and hybrid density functional methods. These calculations
engender two linkage isomers, which correspond to the local minima on the potential-energy surface. In the lowest-energy isomer,
the ligand binds to the metal ion through two oxygens, one from each of the different SO2 groups on the central nitrogen and forms a six-membered ring. Another LiNPSI isomer, wherein the anion coordinates through
oxygen and nitrogen atoms and which is 55.9 kJmol−1 higher in energy, has also been obtained. The S–N–S bond angle in the free anion as well as in the LiNPSI complex turns out
to be nearly 121°. A comparison of the vibrational spectra of the free NPSI anion and that of the LiNPSI complex reveals that
the SO2 stretching vibrations at 1,239 and 1,205 cm−1 can be used to differentiate between the two linkage isomers of the complex. The stronger complexation ability of the NPSI
anion, compared to that for (CF3SO2)2N− has been explained in terms of the charge density within the molecular electrostatic potential isosurface encompassing both
SO2 groups of the anion.
Received: 20 February 2002 / Accepted: 25 March 2002 / Published online: 3 June 2002 相似文献
13.
Galyna Shul Maria A. Murphy Geoff D. Wilcox Frank Marken Marcin Opallo 《Journal of Solid State Electrochemistry》2005,9(12):874-881
Composite electrodes were prepared from chemical vapor deposition grown carbon nanofibers consisting predominantly of ca.
100 nm diameter fibers. A hydrophobic sol–gel matrix based on a methyl-trimethoxysilane precursor was employed and composites
formed with carbon nanofiber or carbon nanofiber—carbon particle mixtures (carbon ceramic electrode). Scanning electron microscopy
images and electrochemical measurements show that the composite materials exhibit high surface area with some degree of electrolyte
solution penetration into the electrode. These electrodes were modified with redox probe solution in 2-nitrophenyloctylether.
A second type of composite electrode was prepared by simple pasting of carbon nanofibers and the same solution (carbon paste
electrode). For both types of electrodes it is shown that high surface area carbon nanofibers dominate the electrode process
and enhance voltammetric currents for the transfer of anions at liquid|liquid phase boundaries presumably by extending the
triple-phase boundary. Both anion insertion and cation expulsion processes were observed driven by the electro-oxidation of
decamethylferrocene within the organic phase. A stronger current response is observed for the more hydrophobic anions like
ClO4− or PF6− when compared to that for the more hydrophilic anions like F− and SO42−.
Presented at the 4th Baltic Conference on Electrochemistry, Greifswald, March 13–16, 2005 相似文献
14.
Erik Rakovský Ľudmila Žúrková Jaromír Marek 《Monatshefte für Chemie / Chemical Monthly》2002,133(3):277-283
Summary. Anhydrous 1,6-hexanediammonium dihydrogendecavanadate ((HdaH2)2H2V10O28, 1) was prepared by reaction of V2O5 with 1,6-hexanediamine in aqueous solution. The crystal structure of 1 was determined, and the proton positions in the H2V10O28
4− anion were calculated by the bond length/bond number method. The protons are bound to the centrosymmetrically oriented μ–OV3 groups of the decavanadate anion. Based on the analysis of IR spectra of 1 prepared from H2O and D2O, the absorption band at 871 cm−1 can be attributed to δ(V–Ob–H) vibrations.
Received August 3, 2001. Accepted (revised) October 8, 2001 相似文献
15.
Functionalized polypyrrole films were prepared by incorporation of Fe(CN)6
3− as doping anion during the electropolymerization of pyrrole at a glassy carbon electrode from aqueous solution. The electrochemical
behavior of the Fe(CN)6
3−/Fe(CN)6
4− redox couple in polypyrrole was studied by cyclic voltammetry. An obvious surface redox reaction was observed and dependence
of this reaction on the solution pH was illustrated. The electrocatalytic ability of polypyrrole film with ferrocyanide incorporated
was demonstrated by oxidation of ascorbic acid at the optimized pH of 4 in a glycine buffer. The catalytic effect for mediated
oxidation of ascorbic acid was 300 mV and the bimolecular rate constant determined for surface coverage of 4.5 × 10−8 M cm−2 using rotating disk electrode voltammetry was 86 M−1 s−1. Furthermore, the catalytic oxidation current was linearly dependent on ascorbic acid concentration in the range 5 × 10−4–1.6 × 10−2 M with a correlation coefficient of 0.996. The plot of i
p versus v
1/2 confirms the diffusion nature of the peak current i
p.
Received: 12 April 1999 / Accepted: 25 May 1999 相似文献
16.
V. L. Lobachev G. P. Zimtseva E. S. Rudakov 《Theoretical and Experimental Chemistry》2005,41(5):302-309
It was found that nitrite anions are effective activators of hydrogen peroxide in the reaction with diethyl sulfide. The observed
kinetics are consistent with the proposed intermediate formation of peroxynitrous acid (ONOOH). The rate constants for the
reaction of diethyl sulfide Et2S with the acid ONOOH (k0 = 1.8⋅103 L/mol⋅s) and with the anion ONOO− (k− = 6⋅10−2 L/mol⋅s) are respectively 105 and three times higher than with hydrogen peroxide.
__________
Translated from Teoreticheskaya i Eksperimental'naya Khimiya, Vol. 41, No. 5, pp. 290–295, September–October, 2005. 相似文献
17.
The possibility of existence of the B6H
6
6−
anion as the analog of the benzene molecule with a planar structure was considered. It was shown that on addition of two
electrons to the [B6H
6
4−
(O
h
)] anion, the change from the octahedral to the planar geometry and the formation of B6H
6
6−
(C
6v
) is thermodynamically unfavorable. The lithium ions in Li6B6H6 can be used as the stabilizing coordination factor in the anion. The occurrence in the B6H
6
n−
ions (n = 2−6) of the shared π-electrons responsible for the formation of the highly aromatic systems with the planar geometry was
shown to be impracticable.
Original Russian Text ? N.T. Kuznetsov, S.P. Ionov, 2007, published in Koordinatsionnaya Khimiya, 2007, Vol. 33, No. 10, pp.
738–741. 相似文献
18.
Thermal decomposition of ammonium dinitramide and mechanism of anomalous decay of dinitramide salts 总被引:1,自引:0,他引:1
A. N. Pavlov V. N. Grebennikov L. D. Nazina G. M. Nazin G. B. Manelis 《Russian Chemical Bulletin》1999,48(1):50-54
Thermal decomposition of ammonium dinitramide proceedsvia homolytic rupture of the N−NO2 bond and partially by the proton transfer reaction. The monomolecular decay of the anion to N2O and NO3
− in the solid state at 60 °C occurs with higher rates than those in the melt. This is related to a change in the reactivity
of the anion due to the violation of its symmetry on going to the solid state. The absence of hydrogen bonds between the anion
and cations or water molecules is an additional condition for the fast decay.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 50–54, January, 1999. 相似文献
19.
Nashwa M. H. Rizk 《Mikrochimica acta》2002,138(1-2):53-58
The construction and electrochemical response characteristics of poly(vinyl) chloride matrix membrane sensors for menadione
(vitamin K3) are described. Membranes incorporating the ion association complexes of menadione anion with bathophenanthroline nickel(II)
and iron(II) as electroactive materials show linear response for menadione over the range 10−1–10−5 M with anionic slopes of 58.2–51.4 mV per concentration decade. Both sensors exhibit fast response time (20–30 s), low detection
limit (2 × 10−5 M), good stability (4–6 weeks) and selectivity coefficient (10−1–10−3). Direct potentiometric determination of menadione under static and hydrodynamic mode of operations shows average accuracies
of 98.8 and 98.5% with relative standard deviations of 0.6% and 1.3%, respectively. Application of the method for the determination
of menadione in human plasma gives favourable results compared with those obtained by the standard spectrophotometric method.
Received February 26, 2001. Revision October 1, 2001. 相似文献
20.
Shan Xi Tian 《Theoretical chemistry accounts》2006,115(4):291-297
The low-lying isomers of Al2H4 and their anions are investigated with the hybrid density functional B3LYP, the coupled-cluster CCSD and CCSD(T) methods,
and the electron propagator theory. The positive adiabatic electron affinities 5,798 and 10,112 cm−1 are predicted for the neutral C2v and D2d symmetric isomers, respectively. The D2h symmetric anion is more stable by 852 cm−1 than the C2v symmetric anion. The photodetachment spectra for Al2H4− anions at the C2v and D2h symmetries are simulated on the basis of the Franck–Condon factor calculations, indicating a reasonable way to study the
transition state of the intramolecular torsion process 相似文献