Structure-dependent band dispersion in epitaxial anthracene films.

The intermolecular band dispersion related to the highest occupied molecular orbital of epitaxial anthracene multilayer films on single-crystalline Bi(0001) has been measured using angle-resolved ultraviolet photoelectron spectroscopy. By comparing the dispersion to that of anthracene multilayers on Cu(110) [F. Bussolotti, Y. Yamada-Takamura, and R. Friedlein, Phys. Rev. B 80, 153402 (2009)], it is shown how the transfer integrals and the difference in on-site energies depend on lattice parameters and how this, in turn, affects the band curvature along high-symmetry directions.