Atomic scattering of H and N on W(100): Effect of lattice vibration and electronic excitations on the dynamics

Abstract

Scattering of H and N atoms from W(100) surface has been theoretically studied by means of classical trajectories based on an electronically adiabatic potential energy surface (PES). The PES has been constructed by interpolation of density functional theory (DFT) calculations following a corrugation reducing procedure (CRP). Van der Waals interactions are taken into account by using the vdW-DF2 exchange- correlation functional. In the dynamics a special focus is made on the influence of energy release through surface atoms motion and electrons of the metal. Most part of the H-atoms sticking is mediated through penetration into the sub-surface area where electron-hole pairs excitation plays the major role. For N-atoms the sticking is mainly due to the coupling with lattice vibrations, as expected when considering heavy atoms. Adsorption and absorption processes have been characterized for both H/W(100) and N/W(100) exhibiting differences between those benchmark light and heavy atoms in interaction with metals.