Fig. 1. Cartoon representation of the molecular architecture embedded between two gold electrodes for distance modulation experiments. Para-Ethynylbenzenethiol expanded porphyrin decks are sketched in light blue, planar bridging xanthene units in grey, and the revolving acetylene joints in light yellow. The anchoring S-Au bonds, mounting the molecule to the electrodes, are depicted as hooks. While the chemical structure is already indicated, please see Fig. 2 for the exact representations of the studied molecules PC1 and ZnPC1.