LAUSR

This study focuses on comparing methods for capturing and measuring the charge transport properties of single molecules in gold–graphene contact gaps. We have attempted to measure the single-molecule conductance of a series of 1,n-alkanedithiols (n = 4, 6, 8) tethered between a gold and a graphene contact with three different methods. The conducting probe atomic force microscopy break junction (CP-AFM BJ), scanning tunneling microscopy (STM) break junction (STM BJ), and STM-based I(s) techniques for forming molecular junctions with graphene lower contacts were compared. In each case, the upper contact was gold, with a gold-coated AFM probe in the CP-AFM BJ method and a gold STM tip for both the STM BJ and I(s) techniques. Both the CP-AFM BJ and the STM-based I(s) methods yielded similar values for the conductance decay constant values, with βN = 0.56 and 0.40, respectively. In line with previous observations, these are much smaller than values recorded for the same alkanedithiol series in symmetric gold–m...