The influence of coronene super-hydrogenation on the coronene-graphite interaction

Skov AW, Andersen M., Thrower JD, Jørgensen B., Hammer B., Hornekær L.

Zusammenfassung

The changes in the strength of the interaction between the polycyclic aromatic hydrocarbon, coronene, and graphite as a function of the degree of super-hydrogenation of the coronene molecule are investigated using temperature programmed desorption. A decrease in binding energy is observed for increasing degrees of super-hydrogenation, from 1.78 eV with no additional hydrogenation to 1.43 eV for the fully super-hydrogenated molecule. Density functional theory calculations using the optB88-vdW functional suggest that the decrease in binding energy is mostly due to an increased buckling of the molecule rather than the associated decrease in the number of π-electrons.