Molecule‐Electrode Interfaces Controlled by Bulky Long‐Legged Ligands in Organometallic Molecular Wires

Precise control of molecule-electrode interface is essential for molecular devices. Herein, new ruthenium acetylide wires with long-legged phosphine ligands to form a sterically controlled are designed. The sharpened Raman signals ascribed acetylene stretching observed the self-assembled monolayers (SAMs) biphenyl- (2Au) and tert-butylbiphenyl-substituted dppe-type (3Au), suggesting that steric hindrance causes formation uniform SAMs. Scanning tunneling microscope break-junction (STM-BJ) study 3Au reveals narrow conductance features compared those 1Au bearing parent dppe ligands, indicating junction. Furthermore, effective electronic interactions between molecule electrodes unique derivatives, as revealed by surface-enhanced scattering study. Thus, bulky strategy turns out provide design concept well-defined interface.