Wiring Up Molecules

By LT-STM we study the formation of and electron delocalization within single molecule wires. Our template for self-assembly of single molecule wires is the highly anisotropic Cu(110)-(2x1)-O surface.  Single Cu atom wide domains of the unoxidized surface act as templates for the self-assembly of single molecule wide wires of C₆₀ molecules.  By local density of states imaging and theory we investigate the nearly-free electron band formation in single molecule wide, up to 50 nm long molecular wires.  the metal-like band formation is enabled by the strong overlap between the superatom states of C₆₀ molecules.

In other experiments we explore the self-assembly of CO molecule gratings on the Cu(110)-(2x1)-O surface.  The one-dimensional nature of the surface gives rise to orthogonal attractive and repulsive forces.  The existence of such forces is a prerequisite for the self-assembly of single molecule wires.  This is a collaboration with Pedro Echenique and coworkers at the Donostia International Physics Center.