Optical properties of palladium in the visible and near UV spectral regions

The dielectric function data, epsilon = epsilon(1) -/+ iepsilon(2), of palladium thin films prepared by dc magnetron sputtering are given for the spectral range 1.6-5.5 eV. A comparison is made between these results and those obtained for Pd films and bulk specimens over the past twenty years. While a number of measurements show good agreement in epsilon(1), there is a considerable variation in the epsilon(2) data among the different groups. Some of these differences can be explained either by the sample preparation, which affects the morphology of the films, or else by uncertainties related to film thickness.