Catalytic Mechanism Of Pd Adsorption On S-Terminated Gaas(001)-(2 X 6) Surface

Structural and electronic properties of Pd adsorption on clean and S-terminated GaAs(001)-(2 x 6) surfaces are studied using first-principle simulations. Our calculations show that the Pd atom prefers to occupy the HH3 site. The Pd atom is lower than the S atom with 0.15 angstrom. The density of states analysis confirms that S-Ga bond plays an important role in Heck reaction. We also find that the Pd catalysis activity for Pd adsorption on clean GaAs(001)-(2 x 6) surface is weak while it is enhanced when the Pd atom is adsorbed on the S-terminated GaAs(001)-(2 x 6) surface, which is in good agreement with the experiments.