The bonding mechanism at bimetallic interface: Pd/Ta(110)

The mechanism responsible for bimetallic bonding in Pd/Ta(110) is investigated using the local density full potential linearized augmented plane wave method with the atomic force approach. A multilayer relaxation in Ta(110) is found to be removed by the Pd adlayer. Charge transfer from the Pd layer to the Ta(110) substrate and the resulting potential barrier in the interfacial region are found to play a significant role. The calculated bonding energy (79 kcal/mol) and the energy shift of the Pd 3d52 core state from that on the clean Pd(001) surface (0.65 eV) agrees well with recent experiments of Goodman et al.