Self-Assembly of a Conjugated Polymer: From Molecular Rods to a Nanoribbon Architecture with Molecular Dimensions

Candidates for molecular nanowires for the interconnection of gold nanoelectrodes in a molecular-scale electronic device are to be found in end-functionalised poly(para-phenyleneethynylene)s. The self-assembly of these polymers was studied on atomically flat solid substrates. On graphite, sub-molecularly resolved imaging with scanning tunneling microscopy revealed nanorods in a 2 D nematic-like texture, while on mica, scanning force microscopy (see picture) shows that the nanorods can self-assemble into highly oriented micrometer-long nanoribbons with a molecular cross-section.