Electronic conductance of helicenes

We report calculations of the electronic properties of helicene molecules. By tuning the radius of the helix and the width of the helix ribbon a helicene can be made semiconducting or metallic. We calculate the I/V characteristic for representatives of selected helicene classes, and analyse their ballistic electronic conductance. For a hybrid metal–semiconductor helicene we show localization of metallic states, and propose the design of a quantum dot based on this phenomenon.