Chemisorption and physisorption of an H atom on a graphenic surface: Interaction potential and sticking probabilities

A complete study on the sticking of a hydrogen atom on the graphene surface has been performed, including energy dissipation in the surface via phonons. The sticking probabilities of H atom in physisorption and chemisorption wells are calculated for the first time in single dynamics calculation. A mixed classical-quantum dynamics method is used. These calculations are parametrized using a Van der Waals functional to obtain potential and phonon modes. In the astrophysical context, our results show that at a grain temperature of 10 K and small initial energy of the H atom, is predominately physisorbed in the v = 1 vibrational state. • The energy dissipation (phonons) in the surface should be included in the dynamics calculation to study the sticking of an H atom on a surface. • The dynamics calculation of the sticking probability of an H atom on a graphenic surface as function of surface temperature and initial energy of the H atom show that the atom can stick in chemisorption and in physisorption. • The sticking of H atom in chemisorption well can take place by tunnelling. • The van der Waals forces at large distance are essential to obtain the best interaction potential in physisorption.