We show that the orientation of pentacene molecules is controlled by the electronic structure of the surface on which they are deposited. We suggest that the near-Fermi level density of states above the surface controls the interaction of the substrate with the pentacene π orbitals. A reduction of this density as compared to noble metals, realized in semimetallic Bi(001) and Si(111)(5×2)Au surfaces, results in pentacene standing up. Interestingly, pentacene grown on Bi(001) is highly ordered, yielding the first vertically oriented epitaxial pentacene thin films observed to date.
ASJC Scopus subject areas
- Physics and Astronomy(all)