Reliably Probing the Conductance of a Molecule in a Cavity via van der Waals Contacts
Ming‐Zhu Huang, Mingjun Sun, Yu Xiang, Suhang He, Simin Liu, Werner M. Nau, Yunchuan Li, Tao Wu, Yun Wang, Shuai Chang, Jin He
Abstract
To address a long-standing issue of building molecular electrical circuits heavily relying on anchoring chemistry, we propose an alternative method to immobilize anchor-free molecules in a molecular cavity between metal electrodes. In such a scheme, well-defined conductance distribution of anchor-free molecules was obtained by means of a scanning tunneling microscopy break-junction technique. Density functional theory calculations suggest that effective electronic coupling at the molecule-electrode interface can be achieved through well-defined van der Waals (vdW) interactions when the molecule is confined in a cavity with a defined geometry. This work offers a new paradigm to achieve reliable conductance measurements of molecules via vdW interaction without metal-binding groups.