Electronic Bandstructure and Transport Properties of Self-Organised Organic-Inorganic Heterostructures

Abstract

We have calculated the hybrid bandstructure formed by the self-organisation of discotic (disk-like) liquid crystal molecules on an ultra-thin Au film. The discotic molecules stack into columns which exhibit one-dimensional transport. When deposited on an inorganic surface, the columns self-organise into a long-range ordered 2-dimensional hexagonal array. The interaction at the surface perturbs the metallic bandstructure, and the regular, periodic nature of the organic overlayer results in the formation of new, hybrid bands. The adsorption and the quantum mechanical coupling between the metallic states and the localised molecular orbitals are modelled by the Newns-Anderson Hamiltonian. The conductivity changes of the film are computed using the Kubo-Greenwood formula.