Pathways of NO adsorption on Si(100) 2 × 1 by van der Waals corrected DFT

In the current study, the NO adsorption on the Si(100) surface was investigated by DFT including van der Waals forces (vdW). Stable molecular and dissociative configurations were found and compared to previous studies. Furthermore, additional states were investigated where NO adsorbs across dimers. The transformation of NO from molecular adsorbate into a dissociated adsorbate migrated into the subsurface was investigated by nudged elastic band. Several pathways were explored, either multi-staged, or direct from molecular into subsurface migrated configurations, both including and excluding vdW forces. The energy barriers of the single steps of multi-staged pathways never exceed 0.15eV and are, in general, smaller when NO is adsorbed across dimers rather than bridged on a single dimer and when including vdW. Furthermore, the oxygen-bridged configurations are kinetically more accessible than the nitrogen-bridged ones.