Solubility and Diffusion of Hydrogen and Deuterium in Platinum

The diffusion and solubility of hydrogen and deuterium in monocrystalline platinum have been studied by a permeation method. The diffusion coefficient of hydrogen is ${\text{D\hspace{0.17em}=\hspace{0.17em}(6.0\hspace{0.17em}±\hspace{0.17em}3.5)\hspace{0.17em}×\hspace{0.17em}10}}^{\text{−3}}\exp \text{(\hspace{0.17em}−\hspace{0.17em}5.9\hspace{0.17em}±\hspace{0.17em}1.0}\mathrm{kcal}\mathrm{/RT)}{\mathrm{cm}}^2{\sec }^{\text{−1}}$ , and the solubility in atom fraction H/Pt is given by ${\text{S\hspace{0.17em}=\hspace{0.17em}1.2\hspace{0.17em}×\hspace{0.17em}10}}^{\text{−3}}\exp \text{(−11}\mathrm{kcal}\mathrm{/RT)}$ . The isotope effects in permeation and diffusion ${\mathrm{(D}}_1{\mathrm{\hspace{0.17em}/\hspace{0.17em}D}}_2\text{\hspace{0.17em}=\hspace{0.17em}1.16\hspace{0.17em}±\hspace{0.17em}0.04}\mathrm{at}\text{750°K)}$ are analyzed in terms of an earlier theory. An Appendix discusses quantitatively errors due to absorption of gas by the walls of the apparatus in this type of experiment.