Normal and off-normal incidence dissociative dynamics of O 2 ( v , J ) on ultrathin Cu films grown on Ru(0001)

BUSNENGO, H. F.; RAMOS, M.; DÍAZ, C.; FALLAQUE, J. G.; MARTÍN, F.

PHYSICAL CHEMISTRY CHEMICAL PHYSICS

ROYAL SOC CHEMISTRY

Lugar: CAMBRIDGE; Año: 2020

1463-9076

Thedissociative adsorption of molecular oxygen on metal surfaces has long been controversial, mostlydue to the spin-triplet nature of its ground state, to possible non-adiabatic effects, such as an abruptcharge transfer from the metal to the molecule, or even to the role played by the surface electronicstate. Here, we have studied the dissociative adsorption of O2on CuML/Ru(0001) at normal andoff-normal incidence, from thermal to super-thermal energies, using quasi-classical dynamics, in theframework of the generalized Langevin oscillator model, and a density functional theory based ona multidimensional potential energy surface. Our simulations reveal a rather intriguing behavior ofdissociative adsorption probabilities, which exhibit normal energy scaling at incidence energies belowthe reaction barriers and total energy scaling above, irrespective of the reaction channel, either directdissociation, trapping dissociation, or molecular adsorption. We directly compare our results withexisting scanning tunneling spectroscopy and microscopy measurements. From this comparison, weinfer that the observed experimental behavior at thermal energies may be due to ligand and straineffects, as already found for super-thermal incidence energies