Showing papers on "Ionic conductivity published in 1969"
TL;DR: In this article, the electrical conductivity of single crystal lithium niobate (LiNbO3) was determined as a function of temperature for various oxygen partial pressures, which can be explained by a defect equilibrium involving singly ionized oxygen vacancies and electrons.
149 citations
TL;DR: In this article, the effect of pressure and temperature on the equivalent conductance of water is derived from recent conductivity measurements, together with experimental data on the ionic conductivity of water at temperatures up to 1000°C and pressures up to 100 kbar.
Abstract: The effect of pressure and temperature on the equivalent conductance of water is derived from recent conductivity measurements. The results together with experimental data on the ionic conductivity of water at temperatures up to 1000°C and pressures up to 100 kbar are discussed. The ionic product of water and the corresponding thermodynamic data for water dissociation at high pressures and temperatures are derived.
95 citations
TL;DR: Inverse conduction occurs when the resistance of the film runs counter to, and direct conduction follows, that of the external solution as mentioned in this paper, and the two types are interconvertible; the controlling factor is the water content of the polymeric film, which is governed by the nature of the polymer, the mode of preparation, and the conditions of exposure.
Abstract: Ionic conduction in continuous polymer films is of two types. Inverse conduction occurs when the resistance of the film runs counter to, and direct conduction when the resistance follows, that of the external solution. The two types are interconvertible; the controlling factor is the water content of the film, which is governed by the nature of the polymer, the mode of preparation of the film, and the conditions of exposure.
75 citations
TL;DR: In this article, the free energy of defect formation and activation energy for motion of the most mobile defect were determined from the ionic conductivity of as-grown and Mg-doped single crystals of lithium iodide.
52 citations
TL;DR: In this paper, high-purity synthetic single crystals of proustite were found to conduct electricity predominantly by motion of Ag+ ions; their transport number is 102±002.
Abstract: At room temperature high-purity synthetic single crystals of proustite were found to conduct electricity predominantly by motion of Ag+ ions; their transport number is 102±002. Evidence from photoconductivity observations shows that electronic conduction can also occur. The lattice dielectric constant is 21±1 independent of orientation at room temperature; at low frequencies higher dielectric constants are measured, due, it is thought, to space-charge effects involving ionic conduction and rate-limiting electrode processes. Effects at contacts and in the bulk during conduction of direct currents are described.
18 citations
TL;DR: In this paper, the authors measured the conductivity of pure and doped KI in the temperature range 200 to 700°c and found that the conductivities of pure KI are much higher than that of Cd2+, Pb2+ and Ca2+.
Abstract: Ionic conductivity of pure and doped KI is measured in the temperature range 200 to 700°c. A large contribution to the conductivity by the anion vacancies is observed in pure KI at high temperatures. The solubility of Ba2+ in KI is much higher than that of Cd2+, Pb2+ and Ca2+. The behaviour of KI doped with Ba2+ is similar to the behaviour of KCl and NaCl doped with divalent cation impurities. The solubility of CO32- in KI is also good. Crystals doped with CO32- show an increase in conductivity at high temperatures owing to the increase in anion vacancy concentration. At lower temperatures the conductivity of KI is suppressed by the CO32- impurity. The values obtained for various energies of activation in KI crystals are Ec = (0·72±0·02) ev for the migration of a cation vacancy, EA = (1·50±0·05) ev for the migration of an anion vacancy, Ws = (1·6±0·1) ev for the formation of a separated pair of Schottky vacancies and Wc similar 0·26 ev for the association of a cation vacancy with Ba2+ impurity.
18 citations
TL;DR: In this paper, the electrical conductivity of synthetic zeolites, types X and Y, was studied to give information about the distribution and possibility of migration of the exchangeable cations located at various sites.
Abstract: The electrical conductivity of synthetic zeolites, types X and Y has been studied to give information about the distribution and possibility of migration of the exchangeable cations, located at various sites. The Na+ samples were exchanged with K+, Cs+, Ag+, Li+, and NH4 +. The various cationic forms were pressed into pellets and treated at 430°C under high vacuum for 24 hours. After cooling, the electrical conductivity and capacity was measured as a function of frequency (500–20,000 c/s) at various temperatures from −20°C up to 500°C. For each sample the reversibility was investigated. The experimental results allow the calculation of the specific conductivity, the real (e′) and imaginary (e″) part of the complex dielectric constant (e*) and the loss factor tgδ. The results show an ionic conductivity: the specific conductivity depends on the nature of the exchangeable cations as follows: Cs+ > K+ > Ag+ > Na+ > Li+. There is a different conductivity mechanism in the high temperature region compared with the low temperature region. At high temperatures (T > 400°K) the activation energy is independent of frequency. At low temperatures, a dielectuc absorption phenomenon occurs. The activation energy, calculated for this process was somewhat higher, but of the same order of magnitude as that of the high temperature region. It is suggested that the migration of the exchangeable cations in the supercage to interstitial positions gives rise to this dipole absorption phenomenon. A comparison of the decationated Y zeolites with Na+ Y and Na+ X made it possible to attribute the conductivity to the cations in the supercage only. The exchangeable cations in the cubo-octahedra and in the hexagonal prisms lower the activation energy of the moving cations. Thus the energy of activation of X zeolites is lower than of Y zeolites.
15 citations
14 citations
13 citations
10 citations
TL;DR: In this paper, the electrical conductivity of pure CsBr was measured between 295 and 895K and the results analysed by least squares and the predicted diffusion coefficients were compared with the experimental values of Lynch.
Abstract: : The electrical conductivity of pure CsBr was measured between 295 and 895K and the results analysed by least squares. Schottky disorder provides an adequate description of the results for the intrinsic conductivity except at the highest temperatures. The predicted diffusion coefficients are compared with the experimental values of Lynch. (Author)
TL;DR: In this article, the migration of cation vacancies in NaCl crystals highly doped with Sr2+ (c < 2 × 10−2) has been studied by means of ionic conductivity.
TL;DR: Antimony electrodeposition from the molten Na2S-Sb2S3 system has been studied in the 800-1000°C temperature range as a function of temp.
TL;DR: The activation energy for migration of a cation vacancy in NaF:Ca is 136 plus or minus 1 eV as discussed by the authors, and an isothermal plot of ionic conductivity vs divalent impurity concentration has been used to analyze several nominally pure NaF samples for impurity levels.
TL;DR: The dielectric polarization theory for ionic conduction at high fields is shown to predict a decrease in the measured ac film capacitance for an increase in the dc ion current, contrary to the assertion of Dell'Oca and Young as discussed by the authors.
Abstract: The dielectric polarization theory for ionic conduction at high fields is shown to predict a decrease in the measured ac film capacitance for an increase in the dc ion current, contrary to the assertion of Dell'Oca and Young.
Patent•
11 Apr 1969