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General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Propriétés des électrolytes: conductivité, Properties of electrolytes: conductivity, Cadmium Chlorure, Cadmium Chlorides, Cadmio Cloruro, Coefficient diffusion, Diffusion coefficient, Coeficiente difusión, Conductivité ionique, Ionic conductivity, Conductividad iónica, Cuivre Chlorure, Copper Chlorides, Cobre Cloruro, Electrolyte solide, Solid electrolyte, Electrólito sólido, Propriété transport, Transport properties, Propiedad transporte, Propriété électrique, Electrical properties, Propiedad eléctrica, Transport ion, Ion transport, and Transporte iónica

In quasi-binary salt system CuCl-CdCl2 where CuCl is the basis compound and CdCl2 is the additive, maximum values of electroconductivity, ion transport number, and diffusion coefficient are determined at 20-30 mol % CdCl2, which points to a maximum ionic disordering. Character of ionic disordering is discussed and predominant conduction by copper(I) ions is proved. X-ray diffraction analysis shows the formation of CuCl-based solid solutions at 20-30 mol % CdCl2. The current efficiency is close to 100%, which guarantees that Faraday's laws are obeyed during coulometric titration of CuCl-CdCl2 of optimum compositions in cells containing a solid electrolyte. The CuCl-CdCl2 system is found to have good ceramic properties. Electrolytic and working characteristics can be stabilized at low temperatures by decreasing hydrolyzability and oxidizability of the solid electrolyte after adding a dopant.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Propriétés des électrolytes: conductivité, Properties of electrolytes: conductivity, Caractéristique capacité tension, Voltage capacity curve, Característica capacidad tensión, Couche mince, Thin film, Capa fina, Cérium Oxyde, Cerium Oxides, Cerio Óxido, Electrolyte solide, Solid electrolyte, Electrólito sólido, Impédance électrique, Electrical impedance, Impedancia eléctrica, Interface électrolyte semiconducteur, Semiconductor electrolyte interface, Interfase electrolito semiconductor, Silicium, Silicon, Silicio, Yttrium Oxyde, Yttrium Oxides, Ytrio Óxido, Zircone stabilisée, Stabilized zirconia, Zircona estabilizada, Zirconium Oxyde, Zirconium Oxides, and Zirconio Óxido

Data obtained in an investigation of yttria-stabilized zirconia (YSZ) and ceria thin films are reviewed and discussed with special regard to the preparation conditions, namely, the temperature of deposition and the post-deposition thermal treatment of films. The structure, phase composition, electrical and dielecric properties, and problems that can be met when measuring effective and real ohmic resistances are compared with the results reported by other authors. The YSZ (CeO2)/Si interfaces are studied by means of deep level transient spectroscopy and feedback charge method capacitance-voltage measurements.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industries chimique et parachimique, Chemical industry and chemicals, Matériaux de construction. Céramique. Verres, Building materials. Ceramics. Glasses, Verres, Glasses, Structure, analyse, propriétés, Structure, analysis, properties, Argent Iodure, Silver Iodides, Plata Ioduro, Argent Oxyde, Silver Oxides, Plata Óxido, Conducteur superionique, Superionic conductor, Conductor superiónico, Etude théorique, Theoretical study, Estudio teórico, Nanostructure, Nanoestructura, Spectre Raman, Raman spectrum, Espectro Raman, Système ternaire, Ternary system, Sistema ternario, Verre borate, Borate glasses, and Système AgI Ag2O B2O3

In the Raman spectra of glasses of (AgI)x(Ag2O . nB2O3)1-x type, along with so-called boson peak (at frequencies of about 10 cm-1), a wide central component is pronounced even at room temperature. The component is similar to that in the spectra of crystalline superionic α-AgI. The emergence of such a central component in the spectra for glasses containing AgI indicates that size effects, which are associated with the glass structure, can significantly modify the relaxation modes associated with ionic conduction. For the first time, low-frequency spectra of superionic glasses are theoretically analyzed taking into account that, in nanocrystalline AgI, the mobile ion concentration is increased. A theoretical treatment of experimental spectra can provide information on important physicochemical characteristics of such glasses.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Propriétés des électrolytes: conductivité, Properties of electrolytes: conductivity, Chimie minerale et origine de la vie, Inorganic chemistry and origins of life, Préparations et propriétés, Preparations and properties, Sels, Salts, Carboxylate, Carboxilato, Conductivité ionique, Ionic conductivity, Conductividad iónica, Diffraction RX, X ray diffraction, Difracción RX, Etude expérimentale, Experimental study, Estudio experimental, Propriété électrique, Electrical properties, Propiedad eléctrica, Sel organique, Organic salt, Sal orgánica, and Rubidium III benzène-1,3,5-tricarboxylate

Salts of trimesic (1,3,5-benzenetricarboxylic) acid generally formulated as Me3[C6H3(COO)3] . 5H2O, where Me = Rb and Cs, are synthesized and their structure and conductivity are examined. Both salts are ionic conductors with conductivities of 4.6 x 10-7 and 2.2 x 10-9 Ω-1 cm-1 at 298 K and activation energies of conduction equal to (1.09 ± 0.02) and (1.07 ± 0.01) eV, respectively.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Cinétique et mécanisme des réactions, Kinetics and mechanism of reactions, Addition nucléophile, Nucleophilic addition, Adición nucleófila, Carbone, Carbon, Carbono, Complexe ylidène, Ylidene complex, Complejo ilideno, Electrode, Electrodes, Electrodo, Etat vitreux, Glassy state, Estado vitreo, Manganèse Carbonyle Complexe, Manganese Carbonyl Complexes, Manganeso Carbonilo Complejo, Mécanisme réaction, Reaction mechanism, Mecanismo reacción, Métal transition Carbonyle Complexe, Transition metal Carbonyl Complexes, Metal transición Carbonilo Complejo, Méthane(dichloro), Dichloromethane, Metano(dicloro), Oxydation, Oxidation, Oxidación, Réaction électrochimique, Electrochemical reaction, Reacción electroquímica, Solvant organique, Organic solvent, Solvente orgánico, Ammonium(tétrabutyl) hexafluorophosphate, Déshydrodimérisation, and Manganèse(η5-cyclopentadiényl styrylidène) complexe

Oxidative dehydrodimerization of some phenylvinylidene complexes of manganese is studied by cyclic voltammetry. In the case of (η5-C5H5)(CO)2Mn=C=C(H)Ph, the process occurs as the homolysis of the Cβ-H bond in the radical cation of {(η5-C5H5)(CO)2Mn=C=C(H)Ph }+. and the dimerization of intermediate σ-phenylethinyl cation [(η5-C5H5)(CO)2Mn-C≡C-Ph]+ to a binuclear dication of bis-carbine type (η5-C5H5)(CO)2Mn+≡C- C(Ph)=C(Ph)-C≡Mn+(CO)2(η5-C5H5). The reduction of the latter leads to binuclear bis-vinylidene complex (η5-C5H5)(CO)2Mn=C=C(Ph)-C(Ph)=C=Mn(CO)2(η5-C5H5). Oxidative dehydrodimerization of complexes (η5-C5R5)(CO)(L)Mn=C=C(H)Ph (R = H, L = PPh3; R = Me, L = CO) occurs through the immediate Cβ-Cβ coupling of radical cations {(η5-C5R5)(CO)(L)Mn=C=C(H)Ph}+. and yields binuclear dication bis-carbine complexes (η5-C5R5)(CO)(L)Mn+≡C-C(H)(Ph)-C(H)(Ph)-C≡Mn+(CO)(L)(η5-C5R5), whose reduction leads to neutral compounds (η5-C5H5)(CO)2Mn=C=C(Ph)-C(Ph)=C=Mn(CO)(L)(η5-C5H5). Complex (η5-C5H5)(CO)2Mn=C=C(Ph)-C(Ph)=C=Mn(CO)2(η5-C5H5) undergoes the oxidation-induced nucleophilic addition of water, forming cyclic bis-carbene product with a bridge heterocyclic ligand (μ-3,4-diphenyl-2,5-dihydro-2,5-diylidene)-bis-(η5-cyclopentadienyldicarbonyl manganese).

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Electrodes: préparations et propriétés, Electrodes: preparations and properties, Autres électrodes, Other electrodes, Composé ternaire, Ternary compound, Compuesto ternario, Conductivité ionique, Ionic conductivity, Conductividad iónica, Effet température, Temperature effect, Efecto temperatura, Gadolinium Oxyde, Gadolinium Oxides, Gadolinio Óxido, Lutétium Oxyde, Lutetium Oxides, Lutecio Óxido, Polycristal, Polycrystal, Policristal, Propriété électrique, Electrical properties, Propiedad eléctrica, Titane Oxyde, Titanium Oxides, and Titanio Óxido

The phase generation in the Lu(Gd)-Ti-O systems is studied at 20-1000°C using a co-precipitation method. During a thermal treatment of co-precipitation products after a sublimation dehydration, for a composition with the Lu: Ti cation ratio of 1: 1, an Lu2Ti2O7 phase with a fluorite structure forms at 650°C. At 730-750°C the phase undergoes a fluorite ⇔ pyrochlore transition. Above 750°C its structure is that of disordered pyrochlore, in which antistructural defects occur in Lu and Ti positions (up to 18%). Above 900°C the structure of pyrochlore becomes ordered, and the number of defects in Lu and Ti positions decreases, which affects the temperature dependence of permittivity of Lu2Ti2O7. In Gd-Ti-O system, Gd2Ti2O7 is crystallized, which has a pyrochlore structure only at 740-900°C. Electroconductivity and permittivity of Lu2Ti2O7 and Gd2Ti2O7 are measured.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Cinétique et mécanisme des réactions, Kinetics and mechanism of reactions, Cathode, Cátodo, Composé organique, Organic compounds, Compuesto orgánico, Cuivre, Copper, Cobre, Electrocatalyse, Electrocatalysis, Electrocatálisis, Hydrogénation, Hydrogenation, Hidrogenación, Hétérocycle azote, Nitrogen heterocycle, Heterociclo nitrógeno, Matériau électrode, Electrode material, Material electrodo, Mercure, Mercury, Mercurio, Nickel, Niquel, Pyridine dérivé, Pyridine derivatives, Piridina derivado, Réaction électrochimique, Electrochemical reaction, Reacción electroquímica, Réduction chimique, Chemical reduction, Reducción química, Stéréoisomère trans, Trans stereoisomer, and Estereoisómero trans

It is shown that the electrocatalytic hydrogenation (ECH) of trans-2-allyl-6-R-1,2,3,6-tetrahydropyridines (R = Me, All, Ph) on a nickel cathode (Nidisp/Ni) in 40-% aqueous DMF in the presence of excess AcOH yields products of total hydrogenation of all double bonds-relevant trans-2-propyl-6-R1-piperidines (R1 = Me, Pr, Ph). Selective hydrogenation of terminal double bonds of allyl substituents in piperideines under study with the retention of the intracycle double bond may be realized on a copper cathode (Cuann), provided the stoichiometric ratio between AcOH and the initial substance is observed exactly. In either case, at points of maximum selectivity of ECH processes, the ratio cACOH/cini = n + 1, where n is the number of hydrogenated bonds. The difference in the ECH mechanisms on the Cuann and Nidisp/Ni cathodes is discussed. The results of hydrogenation of the trans-2-allyl-6-R-1,2,3,6-tetrahydropyridines at the Cuann and Nidisp/Ni cathodes confirm the general character of regularities discovered earlier during ECH of citral.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Cinétique et mécanisme des réactions, Kinetics and mechanism of reactions, Métal transition, Transition metal, Metal transición, Electrode disque, Disk electrode, Electrodo disco, Métal noble, Noble metal, Metal noble, Nucléophile, Nucleophile, Nucleófilo, Oxydation, Oxidation, Oxidación, Phosphine tertiaire, Tertiary phosphine, Fosfina terciaria, Phosphore Composé organique, Phosphorus Organic compounds, Fósforo Compuesto orgánico, Platine, Platinum, Platino, Radical libre cationique, Radical cation, Radical libre catiónico, Réaction électrochimique, Electrochemical reaction, Reacción electroquímica, Réactivité chimique, Chemical reactivity, and Reactividad química

Anodic oxidation of trimesitylphosphine in the presence of typical nucleophilic reactants is studied by cyclic voltammetry. The results and the literature data suggest that the manifestation of radical properties is more typical for radical cations of trimesitylphosphine, because, when realizing an electrophilic path of reacting, additional energy is needed for altering the configuration of radical cations of trimesitylphosphine.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Propriétés des électrolytes: conductivité, Properties of electrolytes: conductivity, Baryum Oxyde, Barium Oxides, Bario Óxido, Composé quaternaire, Quaternary compound, Compuesto cuaternario, Conductivité ionique, Ionic conductivity, Conductividad iónica, Cérium Oxyde, Cerium Oxides, Cerio Óxido, Effet température, Temperature effect, Efecto temperatura, Electrolyte solide, Solid electrolyte, Electrólito sólido, Néodyme Oxyde, Neodymium Oxides, Neodimio Óxido, Propriété électrique, Electrical properties, Propiedad eléctrica, Transition phase, Phase transitions, and Transición fase

Phase transitions in BaCe1-xNdxO3-δ (x = 0-0.15) are studied on ceramic samples by dilatometry (at 370-1100 K) and by measuring electroconductivity (at 750-1220 K). Ion transport numbers are measured by an EMF method at 850-1240 K. All measurements are done in dry air (pH2O = 40 Pa). By treating the obtained temperature dependences of linear expansion with a difference method (difference between first-degree polynomial approximating the dependence and experimental points), the position and the sort of the phase transitions are determined. High-temperature phase transitions are confirmed by measuring the electroconductivity and ion transport numbers. Second-order phase transitions in pure BaCeO3 are discovered at 480 ± 10, 530 ± 10, 900 ± 10, 1030 ± 20, and 1170 ± 10 K and a first-order transition, at 665 ±10 K. Phase transitions at 900 and 1030 K are discovered for the first time ever.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Propriétés des électrolytes: conductivité, Properties of electrolytes: conductivity, Conductivité ionique, Ionic conductivity, Conductividad iónica, Conductivité protonique, Proton conductivity, Conductividad protónica, Conductivité électronique, Electronic conductivity, Conductividad electrónica, Césium Hydrogénosulfate, Cesium Hydrogensulfates, Cesio Hidrógenosulfato, Effet composition, Composition effect, Efecto composición, Electrolyte solide, Solid electrolyte, Electrólito sólido, Etain IV Oxyde, Tin IV Oxides, Estaño IV Óxido, Impédance électrique, Electrical impedance, Impedancia eléctrica, Propriété électrique, Electrical properties, Propiedad eléctrica, Schéma équivalent, Equivalent circuit, and Esquema equivalente

Dependence of electronic and ionic components of conductance of CsHSO4-SnO2 systems on their composition is studied using the method of electrochemical impedance. The total electronic and ionic components of conductance nonmonotonically depend on the composition. To describe completely impedance diagrams of composite materials, an equivalent electrical circuit is proposed, which contains the bulk ionic conductance corresponding to the bulk of CsHSO4 grains, and the conductance corresponding to the surface of tin dioxide grains. Each conductance component is separated out. The activation energies for the bulk and surface conduction equal 0.32 ± 0.02 and 0.36 ± 0.02 eV, respectively, and are independent of the system composition. The bulk ionic conductance monotonically decreases with increasing SnO2 content and is well described wit percolation theory, whereas dependences of surface ionic and total electronic components have extremums.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Cinétique et mécanisme des réactions, Kinetics and mechanism of reactions, Métal transition Complexe, Transition metal Complexes, Metal transición Complejo, Acétonitrile, Acetonitrile, Acetonitrilo, Aluminium, Aluminio, Bipyridyle, Bipyridines, Coordinat organique, Organic ligand, Ligando orgánico, DMF, N,N-Dimethylformamide, Dimetilformamida, Electrocatalyse, Electrocatalysis, Electrocatálisis, Electrode, Electrodes, Electrodo, Halogène Composé organique, Halogen Organic compounds, Halógeno Compuesto orgánico, Magnésium, Magnesium, Magnesio, Nickel Complexe, Nickel Complexes, Niquel Complejo, Phosphore Composé organique, Phosphorus Organic compounds, Fósforo Compuesto orgánico, Phosphore, Phosphorus, Fósforo, Réaction électrochimique, Electrochemical reaction, Reacción electroquímica, Réduction chimique, Chemical reduction, Reducción química, Solvant organique, Organic solvent, Solvente orgánico, and Zinc

Electrochemical reduction of nickel complexes with 2,2'-bipyridyl in the presence of ortho-substituted aromatic bromides or white phosphorus leads to the formation of highly reactive organonickel 6-complexes that are capable of selectively reacting with diverse substrates with the formation of cross-association products. Mechanisms of electrocatalytic processes involving organic halides, chlorophosphines, white phosphorus, and nickel complexes with 2,2'-bipyridyl are studied by the cyclic voltammetry and preparative electrolysis methods. Key intermediates of processes that occur in metallocomplex catalysis are determined.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Propriétés des électrolytes: conductivité, Properties of electrolytes: conductivity, Conductivité ionique, Ionic conductivity, Conductividad iónica, Electrolyte polymère, Polymer electrolytes, Lithium Hexafluorophosphate, Lithium Hexafluophosphates, Litio Hexafluorofosfato, Lithium Perchlorate, Lithium Perchlorates, Litio Perclorato, Lithium Tétrafluoroborate, Lithium Tetrafluoborates, Litio Tetrafluoroborato, Méthacrylate copolymère, Methacrylate copolymer, Metacrilato copolímero, Propriété électrique, Electrical properties, Propiedad eléctrica, Propène oxyde copolymère, Propylene oxide copolymer, Propeno óxido copolímero, Uréthanne copolymère, Urethane copolymer, Uretano copolímero, 1,3-Dioxolan-2-one, Carbonate(diméthyl), Electrolyte gel polymère, and Furan-2-one(perhydro)

Novel polymer gel electrolytes (PGE) based on a composition of oligourethane methacrylate, polypropylene glycol monomethacrylate, and 1 M solutions of LiClO4 or γ in LiBF4-butyrolactone or LiPF6 in ethylene carbonate/dimethyl carbonate (1: 1 by volume) are synthesized and studied. The electrolyte films are solidified from liquid PGE solutions by irradiating the latter with UV light. Impedance spectroscopy shows PGE to have conductivity of about 3.0 x 10-3 S cm-1 at room temperature. To enhance mechanical strength of PGE, the electrolyte solutions are applied onto a fiber polypropylene separator and then photosolidified. The temperature dependences of the bulk conductivity and the charge transfer resistance through the Li/PGE interface are studied. The best PGE is that based on a 1 M LiClO4 solution in γ-butyrolactone containing 20 wt % of the polymer composite.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie minerale et origine de la vie, Inorganic chemistry and origins of life, Préparations et propriétés, Preparations and properties, Sels complexes, Coordination compounds, Métal transition, Transition metal, Metal transición, Acétonitrile, Acetonitrile, Acetonitrilo, Coordinat organique, Organic ligand, Ligando orgánico, Electrode, Electrodes, Electrodo, Hétérocycle azote, Nitrogen heterocycle, Heterociclo nitrógeno, Imine, Imina, Macrocycle, Macrociclo, Métal noble, Noble metal, Metal noble, Métal transition Complexe, Transition metal Complexes, Metal transición Complejo, Nickel complexe, Nickel complex, Níquel complejo, Platine, Platinum, Platino, Propriété électrochimique, Electrochemical properties, Propiedad electroquímica, Solvant organique, Organic solvent, Solvente orgánico, Synthèse chimique, Chemical synthesis, Síntesis química, and Ammonium(tétrabutyl) tétrafluoroborate

Complexes of Ni(ClO4)2 with 1,4-bis(2-aminobenzyl)piperidine (1) and 1,4-bis(2-amino-4-tertbutyl)piperidine (2) and products of their cyclization with ortho-phthalic aldehyde in methanol [NiL3][ClO4]2 (3) and [NiM4][ClO4]2 (4), respectively, are synthesized. Complexes 1 and 2 can be reduced on a platinum electrode irreversibly. Cyclic complexes 3 and 4 undergo reduction reversibly or quasi-reversibly in two or three stages. The reduction products react with n-BuI or n-BuBr (Bu = butyl) via an inner-sphere mechanism of oxidative attachment, probably, with the formation of the Ni-C bond.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Cinétique et mécanisme des réactions, Kinetics and mechanism of reactions, Amine aromatique, Aromatic amine, Amina aromática, Cation organique, Organic cation, Catión orgánico, Cinétique, Kinetics, Cinética, Halogène Composé organique, Halogen Organic compounds, Halógeno Compuesto orgánico, Hétérocycle oxygène, Oxygen heterocycle, Heterociclo oxígeno, Mécanisme réaction, Reaction mechanism, Mecanismo reacción, Réaction électrochimique, Electrochemical reaction, Reacción electroquímica, Substitution nucléophile, Nucleophilic substitution, Substitución nucleófila, and Pyrylium composé

Stoichiometry and kinetics of reactions of 2,6-diphenyl-4-chloropyrylium, 4-chloroflavylium, 4-bromoflavylium, and 4-iodoflavylium perchlorates with nucleophiles N,N-dimethylaniline and n-phenylene-diamine are studied using cyclic voltammetry and spectroscopy. Nucleophilic substitution in these compounds proceeds via the formation of a charge-transfer complex, which converts into a radical ion pair as a result of the electron transfer. Heterolytic clevage of the C-Hal bond occurs at the stage of pyranyl (flavanyl) radical.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Propriétés des électrolytes: conductivité, Properties of electrolytes: conductivity, Acrylonitrile copolymère, Acrylonitrile copolymer, Acrilonitrilo copolímero, Butadiène copolymère, Butadiene copolymer, Butadieno copolímero, Conductivité ionique, Ionic conductivity, Conductividad iónica, Electrolyte solide polymère, Polymer solid electrolyte, Electrólito sólido polímero, Etude expérimentale, Experimental study, Estudio experimental, Lithium Hexafluoroarséniate, Lithium Hexafluoarsenates, Litio Hexafluoroarseniato, Propriété électrique, Electrical properties, and Propiedad eléctrica

The ionic structure and transport properties intrinsic to solid polymer electrolytes based on an acrylonitrile-butadiene (40: 60) copolymer and lithium hexafluoroarsenate are studied at the salt concentrations close to the salt solubility limit in the polymer matrix. The ionic structure of a macromolecular ionic solution alters with increasing salt concentration and temperature, as does the ionic-transport mechanism. Possible models for the ionic structure of concentrated solid polymer electrolytes and ionic-transport mechanisms corresponding to them are considered.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Propriétés des électrolytes: conductivité, Properties of electrolytes: conductivity, Métal transition Ion, Transition metal Ions, Metal transición Ión, Argent Iodure, Silver Iodides, Plata Ioduro, Diffraction RX, X ray diffraction, Difracción RX, Etude expérimentale, Experimental study, Estudio experimental, Insertion, Inserción, Lanthanide Ion, Lanthanide Ions, Lantánido Ión, Manganèse Ion, Manganese Ions, and Manganeso Ión

The interaction of manganese and some 4f-metals (M) with silver iodide is studied. The samples are obtained by sputtering M onto the surface of polycrystalline AgI films (∼0.2 μm, ∼300 K) in a vacuum. Optical absorption in the samples is interpreted as the insertion of M ions into AgI with the formation of dopants AgI:M. A new phase with an optical bandgap of ∼3.7 eV emerges in the samples with elevated concentrations of La, Ce, Pr, Nd, Sm, or Dy (nM/nAg ∼ 0.1). X-ray diffraction patterns for such samples with Sm correspond to structures with large interfacial distances, for example, 0.99, 0.87, 0.76, and 0.67 nm. In air, AgI forms in the samples with a new phase; this process is hindered by the sputtered protective coatings. According to optical absorption data, X-ray diffraction, and local microanalysis the Mn insertion into AgI is followed by the formation of a new phase (2Ag:Mn:4I), which may belong with solid electrolytes Ag2MI4, where nonmagnetic M are known (Zn, Cd, Sn, Hg, Pb).

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Cinétique et mécanisme des réactions, Kinetics and mechanism of reactions, Métal transition, Transition metal, Metal transición, Acétonitrile, Acetonitrile, Acetonitrilo, Azole, Azol, Electrode, Electrodes, Electrodo, Hétérocycle azote, Nitrogen heterocycle, Heterociclo nitrógeno, Mécanisme réaction, Reaction mechanism, Mecanismo reacción, Métal noble, Noble metal, Metal noble, Platine, Platinum, Platino, Réaction électrochimique, Electrochemical reaction, Reacción electroquímica, Solvant organique, Organic solvent, Solvente orgánico, Synthèse chimique, Chemical synthesis, Síntesis química, Ammonium(tétrabutyl) perchlorate, and Benzène(1,4-diméthoxy)

An analysis is performed and data are compared on the electrosynthesis of N-arylazoles and regularities of this process in conditions of a diaphragmless galvanostatic electrolysis (Pt, MeCN, Bu4NClO4) of a mixture of 1,4-dimethoxybenzene (DMB) with azoles (pyrazole, triazole, their derivatives, tetrazole). Electrolysis of an azole/DMB mixture leads to the formation of products of an ortho-substitution-1,4-dimethoxy-2-(azolyl-1)benzenes-and, simultaneously, hydrolytically unstable products of an ipso-bis-attachment-1,4-dimethoxy-1,4-di-(azolyl-1)cyclohexa-2,5-dienes. The overall yield of these compounds increases upon adding a base (collidine) or an acid (AcOH) into the initial mixture, and the basicity of initial azoles substantially affects the electrosynthesis results. New notions on the nature of nucleophilic species interacting with radical cation of DMB are considered. The species in question are complexes of azoles with one another or with collidine generated at the expense of the hydrogen bond, rather than azolate ions. Furthermore, the cathodic process is largely connected not with the generation of azolate ions (as a result of the reduction of initial azoles) but with the deprotonation of onium compounds (BH+)-products of the interaction of azoles or collidine with protons. The mechanism of electrosynthesis of N-arylazoles is discussed. The key stages of the synthesis are the attack of a nucleophile on the ipso- and, possibly, ortho-positions of the benzene ring of radical cation of DMB, as well as the rearrangement of the intermediate cation of 1,4-dimethoxy-1-(azolyl-1)arenonium into the cation of 1-(azolyl-1)-2,5-dimethoxyarenonium, which affects both the yield and ratio of final products of the reaction mixture.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Cinétique et mécanisme des réactions, Kinetics and mechanism of reactions, Décyclisation, Ring cleavage, Desciclización, Electrode goutte, Dropping electrode, Electrodo goteo, Hétérocycle azote, Nitrogen heterocycle, Heterociclo nitrógeno, Hétérocycle soufre azote, Sulfur nitrogen heterocycle, Heterociclo azufre nitrógeno, Mercure, Mercury, Mercurio, Mécanisme réaction, Reaction mechanism, Mecanismo reacción, Phtalazine dérivé, Phthalazine derivatives, Réaction électrochimique, Electrochemical reaction, Reacción electroquímica, Réduction chimique, Chemical reduction, Reducción química, Spectrométrie RPE, EPR spectrometry, Espectrometría RPE, Thiadiazole dérivé, Thiadiazole derivatives, Tiadiazol derivado, and 1,2,5-Thiadiazole dérivé

Electrochemical reduction of phthalazines and 1,2,5-thiadiazoles containing nucleofugaceous groups at the carbon α-atoms are studied in aprotic and proton-donating media. Heteroatoms, substituents, and media are found to affect potentials and reaction path for the electroreduction. The factors determining the reductive opening of heterocycles are revealed. In diazines the heterocycle opening in annelated systems is induced by the electron transfer, provided there exist (a) a heteroatom-heteroatom bond and (b) an easily splitting-off group at the carbon α-atom, whose nucleofugacity is comparable with or exceeds that of the chloride ion. Stability of the 1,2,5-thiadiazole cycle toward its reduction is determined by the substituent and the medium nature. On adding a nucleofugaceous group to the molecule, the transfer of two electrons in an aprotic medium results in the heterocycle opening with the formation of iminonitrile; when two easily splitting-off groups are present, the electron transfer makes the cycle decompose into inorganic anions.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Cinétique et mécanisme des réactions, Kinetics and mechanism of reactions, Composé organique, Organic compounds, Compuesto orgánico, Ester, Hydrodimérisation, Hydrodimerization, Hidrodimerización, Nitrile, Nitrilo, Réaction électrochimique, Electrochemical reaction, Reacción electroquímica, Réduction chimique, Chemical reduction, Reducción química, Acrylique acide(3-aryl-2-cyano) ester éthyle, and Ethylène-1,1-dicarbonitrile(2-aryl)

The electrochemical reduction of compounds with a common formula R1(H)C=C(CN)R2, where R1 is C6H5, n-CH3OC6H4, n-FC6H4, or α-furyl; and R2 is CN or COOC2H5 is studied. The reduction of these compounds at a zinc cathode in the water-acetonitrile KH2PO4 solution yields both cyclic and linear hydrodimers. The relative yield of the linear hydrodimer increases with lowering the temperature and acetonitrile content in the catholyte. The obtained data well correlate with the suggestion that the cyclic products form in the catholyte bulk from linear hydrodimers.

General chemistry, physical chemistry, Chimie générale, chimie physique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Electrochimie, Electrochemistry, Cinétique et mécanisme des réactions, Kinetics and mechanism of reactions, Acétonitrile, Acetonitrile, Acetonitrilo, Carbone, Carbon, Carbono, Electrode, Electrodes, Electrodo, Etat vitreux, Glassy state, Estado vitreo, Hétérocycle azote, Nitrogen heterocycle, Heterociclo nitrógeno, Mécanisme réaction, Reaction mechanism, Mecanismo reacción, Oxydoréduction, Oxidation reduction, Oxidación reducción, Pyrazole dérivé, Pyrazole derivatives, Pirazol derivado, Réaction électrochimique, Electrochemical reaction, Reacción electroquímica, Solvant organique, Organic solvent, Solvente orgánico, Spectrométrie RPE, EPR spectrometry, Espectrometría RPE, Transfert électron, Electron transfer, Transferencia electrón, Ammonium(tétraéthyl) perchlorate, Pyrazol-5-one dérivé, and Pyrazole-5-thione dérivé

Electron transfer processes in a series of pyrazole-2-in-5-ones (pyrazolones-5) and some of their thioanalogues are studied experimentally and theoretically for the first time. The electrochemical behavior of thiopyrazolones and oxygen analogues is found to differ. The effect the nature of the electrode, heteroatom, and substituents exerts on the redox potentials is established. Schemes of redox processes for the compounds studied in nonaqueous media are suggested. The schemes take account the ability of pyrazolones-5 to autoprotonation. Electrooxidation of l-phenyl-3-methyl-4-benzoylpyrazole-2-in-5-one and its thioanalogues is shown to occur similarly to electroless oxidation with the formation of various dimers. It is established that, in the absence of active substituents during the electroreduction of compounds under study, the reaction center is the pyrazolone cycle, whose reduction does not involve decomposition of heterocyclic system.