Direct Observation of a Widely Spaced Periodic Row Structure at the Pentacene/Au(111) Interface Using Scanning Tunneling Microscopy

Abstract

The transition from surface to bulk pentacene at the Au(111) interface will have important implications for the mechanism of carrier transport across the interface. STM observations of pentacene molecules on the Au(111) surface, at more than a monolayer coverage, revealed periodic rows of molecules spaced 61 ± 5 Å apart. These widely spaced periodic rows consist of flat and edge-on molecules aligned with the initial layer of pentacene. Commensuration with the surface and characteristic bulk pentacene−pentacene interactions drive the formation of this unique structure.