Pi-stacked pentacene thin films grown on Au(111)

Scanning tunneling microscopy with high impedance has been used to image the growth of pentacene thin films on Au(111). Instead of the herringbone structure in bulk solid, pentacene molecules in these thin films form a cofacial, π-stacked crystalline phase with their molecular planes parallel to the surface. The growth of this crystalline phase is attributed to the formation of a close-packed, crystalline monolayer which seeds the growth of the π-stacked multilayer film.