title: Omni-conducting and omni-insulating molecules.
abstract: The source and sink potential model is used to predict the existence of omni-conductors (and omni-insulators): molecular conjugated π systems that respectively support ballistic conduction or show insulation at the Fermi level, irrespective of the centres chosen as connections. Distinct, ipso, and strong omni-conductors/omni-insulators show Fermi-level conduction/insulation for all distinct pairs of connections, for all connections via a single centre, and for both, respectively. The class of conduction behaviour depends critically on the number of non-bonding orbitals (NBO) of the molecular system (corresponding to the nullity of the graph). Distinct omni-conductors have at most one NBO; distinct omni-insulators have at least two NBO; strong omni-insulators do not exist for any number of NBO. Distinct omni-conductors with a single NBO are all also strong and correspond exactly to the class of graphs known as nut graphs. Families of conjugated hydrocarbons corresponding to chemical graphs with predicted omni-conducting/insulating behaviour are identified. For example, most fullerenes are predicted to be strong omni-conductors.
authors: Department of Chemistry, The University of Sheffield, Sheffield S3 7HF, United Kingdom.
authors: P W
authors: PW
authors: Fowler
authors: Department of Chemistry, The University of Sheffield, Sheffield S3 7HF, United Kingdom.
authors: B T
authors: BT
authors: Pickup
authors: Department of Chemistry, The University of Sheffield, Sheffield S3 7HF, United Kingdom.
authors: T Z
authors: TZ
authors: Todorova
authors: Department of Chemistry, The University of Sheffield, Sheffield S3 7HF, United Kingdom.
authors: Martha
authors: M
authors: Borg
authors: Department of Mathematics, Faculty of Science, University of Malta, Msida MSD 2080, Malta.
authors: Irene
authors: I
authors: Sciriha