Browsing by Author "Oates, W. A."

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    Isotope effect for the solution of hydrogen in metals: application to Pd/H(D)
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1977, 73 (03), 1977) Oates, W. A.; Flanagan, Ted B.
    The isotope effect for the solution of hydrogen in metals cannot be described over the whole temperature range by the usually employed model of localized oscillators. Consideration is given to the transition from localized harmonic oscillator behaviour at the lowest temperatures to that of a three-dimensional translator at the highest temperatures. Application of this new model to the Pd/H(D) system reveals that the experimental isotope solubility ratio data do not agree with the theoretical expectations. At low temperatures the isotope data are in disagreement with the Einstein characteristic temperature, θH= 795 K, determined by inelastic neutron scattering, if θD=θH/√2 is assumed. The isotopic solubility ratio data are also contrary to expectations at higher temperatures. The discrepancies are removed if it is assumed that θD=θH/1.53, a choice which is not unrealistic in view of recent interpretations of the inverse isotope effect observed for the super-conductive transition temperatures of Pd/H(D) alloys.
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    Thermodynamic Properties of Hydrogen and Deuterium Dissolved in Palladium at Low Concentrations over a Wide Temperature Range
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1973, 69 (2), 1973) Clewley, J. D.; Curran, T.; Flanagan, Ted B.; Oates, W. A.
    The equilibrium pressures of the Pd/H2 and Pd/D2 systems have been measured in the tempera ture range from — 100°C to 35O°C for values of H(D)-to-Pd, atomic ratio, in the approximate range from 0.0005 to 0.005. These data were obtained in an ultra-high vacuum apparatus with large samples of low surface area. Partial thermodynamic data have been obtained from these equilibrium data; a significant temperature dependence is reported for the relative partial molar enthalpies and entropies.