Inspired by the complex molecular machines found in nature, chemists have developed much simpler molecular motors.[1–3] Among them, several systems incorporating azobenzene have been proposed, which exploit the reversible trans–cis isomerization triggered by light [4] or an electric field [5] for applications such as optical data-storage devices,[6] switchable supramolecular cavities, and sensors.[7] Recently, it has been demonstrated that the photoisomerization process of individual polymer chains incorporating azobenzenes can express mechanical work.[8] In light of these findings, one can foresee self-assembled monolayers (SAMs)[9, 10] of aromatic azobenzenes as molecular systems able to express forces of unprecedented magnitude by exploiting a collective subnanometer structural change. We recently designed a rigid and fully conjugated azobenzene exposing a thiol anchoring group,[11] which …