Magic ratios for connectivity-driven electrical conductance of graphene-like molecules
Abstract
Experiments using a mechanically-controlled break junction and calculations based on density functional theory demonstrate a new magic ratio rule (MRR),which captures the contribution of connectivity to the electrical conductance of graphene-like aromatic molecules. When one electrode is connected to a site i and the other is connected to a site i' of a particular molecule, we assign the molecule a magic integer Mii'. Two molecules with the same aromatic core, but different pairs of electrode connection sites (i,i' and j,j' respectively) possess different magic integers Mii' and Mjj'. Based on connectivity alone, we predict that when the coupling to electrodes is weak and the Fermi energy of the electrodes lies close to the centre of the HOMO-LUMO gap, the ratio of their conductances is equal to (Mii' /Mjj')2. The MRR is exact for a tight binding representation of a molecule and a qualitative guide for real molecules.
Keywords
Cite
@article{arxiv.1509.00982,
title = {Magic ratios for connectivity-driven electrical conductance of graphene-like molecules},
author = {Yan Geng and Sara Sangtarash and Cancan Huang and Hatef Sadeghi and Yongchun Fu and Wenjing Hong and Thomas Wandlowski and Silvio Decurtins and Colin J. Lambert and Shi-Xia Liu},
journal= {arXiv preprint arXiv:1509.00982},
year = {2015}
}