Accession Number : AD0647366

Title :   ISOTOPE EFFECTS IN THE DIFFUSION AND SOLUBILITY OF HYDROGEN IN NICKEL AND QUANTUM MASS EFFECTS IN DIFFUSION.

Descriptive Note : Technical rept.,

Corporate Author : ARIZONA STATE UNIV TEMPE DEPT OF CHEMISTRY

Personal Author(s) : Ebisuzaki,Y. ; Kass,W. J. ; O'Keeffe,M.

Report Date : 01 JAN 1967

Pagination or Media Count : 31

Abstract : The solubility and diffusivity of hydrogen and deuterium in a single crystal of nickel have been measured in the range 490-690K. The theory of isotope effects has been developed in the harmonic approximation. It is shown that the experimental results can be quantitatively accounted for in terms of the derived expressions. The theory is tested by calculation of the pre-exponential factor for diffusion (Do) using only the data for the relative diffusivities of hydrogen and deuterium. The calculated value is in excellent agreement with experiment if it is assumed that direct jumps of hydrogen from one octahedral site to another are involved. A supplementary note discusses the temperature dependence of the ratio of isotope diffusion coefficients with particular reference to hydrogen in metals.

Descriptors :   (*ISOTOPE SEPARATION, *HYDROGEN), (*QUANTUM STATISTICS, *DIFFUSION), NICKEL, TEMPERATURE, DEUTERIUM, GASEOUS DIFFUSION SEPARATION, PARTIAL DIFFERENTIAL EQUATIONS, SOLUBILITY

Subject Categories : Quantum Theory and Relativity

Distribution Statement : APPROVED FOR PUBLIC RELEASE