Dynamical corrugation: simulations of the sticking of CO on Cu(100)

摘要: Abstract Molecular dynamics (MD) simulations have been carried out of the non-dissociative sticking probability carbon monoxide on clean (1 0 0) face a copper crystal, as function incident translational energy, Etr, and angle with respect to surface normal, θ. The computed probabilities do not obey standard functional dependence E tr cos n θ . Rather, in order fit this form, exponent must vary from usual positive values at low energies negative high energies, crossover 0.5 eV. A reflects higher normal incidence than oblique for same energy. This suggests that effective corrugation is energy dependent very pronounced above eV, spite fact Cu(1 0 0) smooth crystal its interaction intact CO chemically simple. Similar behavior has observed experimentally related systems, Ni(1 0 0) NO Pt(1 1 1). In identify source apparent strong corrugation, we MD which moment inertia molecule was artificially altered. We show deeper penetration into negligible effect. major contribution large, energy-dependent dynamic one; molecular axis time continuously reorient energetically favorable directions, whereas orientational “steering” much less complete. This, conjunction directionality CO–Cu(1 0 0) binding, produces large conclude will apply generally molecule–surface systems lateral degrees freedom are strongly coupled.