Conductance of Au/1,4-benzenedicarbothioamide/Au molecular junctions: A proposal for a potential linker

Abstract

We studied the conductance of Au/1, 4-benzenedicarbothioamide (BDTA)/Au junctions at room temperature and measured a single-molecule conductance of BDTA. A carbothioamide (thioamide, –CSNH[2]) group of this molecule consists of two potential linkers, thioketone and amine groups, and would thus be expected to show high conductance. The experimental single-molecule conductance of BDTA is (0.8–1.0)×10[-3]G[0] which roughly compares with that of π-conjugated molecules. We consider that this relatively high conductance of Au/BDTA/Au is due to the homoconjugation of π-orbitals of benzene and sulfur while the amine group is likely to remain as a side group. We also observed that Au/BDTA/Au junctions can exist in multiple configurations of different conductances.