The current–voltage characteristics of a single-molecule
junction are determined by the electronic coupling Γ between
the electronic states of the electrodes and the dominant transport
channel(s) of the molecule. Γ is profoundly affected by the
choice of the anchoring groups and their binding positions on the
tip facets and the tip–tip separation. In this work, mechanically
controllable break junction experiments on theN,N′-bis(5-ethynylbenzenethiol-salicylidene)ethylenediamine
are presented, in particular, the stretch evolution of Γ with
increasing tip–tip separation. The stretch evolution of Γ
is characterized by recurring local maxima and can be related to the
deformation of the molecule and sliding of the anchoring groups above
the tip facets and along the tip edges. A dynamic simulation approach
is implemented to model the stretch evolution of Γ, which captures
the experimentally observed features remarkably well and establishes
a link to the microscopic structure of the single-molecule junction.