Charge transfer and adsorption energies in the iodine-Pt(1Â 1Â 1) interaction

The adsorption energies for iodine atom on the fcc, hcp, bridge, and atop sites of the Pt(1 1 1) surface were determined using ab initio DFT method in two different unit cells. A periodic slab model is used and the obtained energies are in agreement with the corresponding experimental values extrapolated at 0 K. The charge transfer is determined by the use of the Hirshfeld partitioning scheme, and the charge transfer values follow the adsorption energy trend for different sites of the Pt(1 1 1) surface. The results show that the plane-wave DFT approach correctly describes the adsorption of iodine on the Pt(1 1 1) surface and support the use of the Hirshfeld method in surface science problems.