Surface temperature dependence of rotational excitation of H-2 scattered from Pd(111) - art. no. 127601

Classical dynamics simulations are performed to study rotational excitation of H-2 scattered from Pd(111), taking into account energy exchange with su rface phonons through a 3D surface oscillator model. We show that dynamic t rapping, identified recently in the study of dissociation dynamics, plays a prominent role. The corresponding long interaction time due to several rec ollisions allows an efficient energy exchange between H-2 molecules and sur face phonons. This microscopic mechanism explains, the puzzling experimenta l finding on the role of surface temperature in H-2(nu = 0, J = 1 --> 3) ex citation.