Electrical Resistivity Versus Deuterium Concentration in Palladium

The electrical resistivity of the palladium-deuterium system has been measured up to a deuterium-to-palladium atom ratio of 0.9 at temperatures of 273, 77, and 4.2 K. The resistivity ratio $\frac{{\rho }_x}{{\rho }_0}$ was plotted versus the atom ratio $x$ at 273 and 4.2 K. The structural resistivity has been calculated, assuming two types of scattering centers associated with the deuterium having widely different screening radii. A good fit with the data at 4.2 K is obtained by assuming that the number of $d$ holes per Pd atom takes on the value 0.55-0.60 upon addition of deuterium.