On the role of physisorption states in molecular scattering: A   semi-local density-functional theory study on O2/Ag(111)
  We simulate the scattering of O$_2$ from Ag(111) with classical dynamics simulations performed on a six-dimensional potential energy surface calculated within semi-local density-functional theory (DFT). The enigmatic experimental trends that originally required the conjecture of two types of repulsive walls, arising from a physisorption and chemisorption part of the interaction potential, are fully reproduced. Given the inadequate description of the physisorption properties in semi-local DFT, our work casts severe doubts on the prevalent notion to use molecular scattering data as indirect evidence for the existence of such states. 
I. Goikoetxea, J. Meyer, J.I.Juaristi, M. Alducin and K. Reuter
cond-mat.mtrl-sci cond-mat.stat-mech physics.chem-ph physics.comp-ph