Metallophilicity Enhances Electron Transport through Parallel Organometallic 1D Chain Junctions Formed In Situ

Abstract

We reveal the role of aurophilic interactions in the formation and conductance of gold cyanide molecular wires of variable length-to-width ratios assembled at the tip of an STM break junction in ambient conditions. Specifically, we identify electron transport signatures through 1D single chains containing variable number of monomeric repeats of gold cyanide AuCN, linked in series (AuCN)n, and through adjacent molecular wires linked in parallel. When bound in series, destructive quantum interference causes an exponential decay of conductance in (AuCN)n 1D wires for n=1-3. But when bound in parallel, aurophilic coupling through the gold atoms of neighboring chains reorders electronic states and results in significant enhancement of conductance. Our work reveals that metallophilicity can play a significant role in junction assembly and electron transport characteristics.