Experimental energy dispersions for valence and conduction bands of palladium

Using angle-resolved photoemission with synchrotron radiation, we have determined accurate energy-versus-momentum dispersion relations along the 〈111〉 direction using a Pd (111) crystal. The energy E (0. 1 eV accuracy) and the momentum parallel to the surface {k}_ are measured directly. The perpendicular component of the momentum k_ is obtained from the measured final energy via a calculated free-electron-like final band that is found to be accurate within 5% of the zone-boundary momentum by comparison with certain critical points that have been measured directly (L₁, {^'}₂, and ₁₅). For the initial bands, we find the dispersions of the two d-like ₃ bands and of the sp-type ₁ band. Measured critical points (in eV) for bands numbered with increasing energy are: ₂, ₃, ₄=-2. 550. 15, ₅, ₆=-1. 150. 1, ₇=18. 40. 5, ₈=21. 70. 5, L₄=-0. 40. 2, L₅-0. 10. 1, and L₇=7. 70. 3. Spin-orbit splitting (0. 4 eV maximum) is observed for the upper ₃ band.