appear even more clearly in Figure .b, where the UV/Vis absorption spectra computed for the QM, GAFF and QMD-FF optimized geometries are displayed and compared. The lack of specificity in reproducing the bond length alternation (BLA) in the aromatic units when using GAFF results in a significantly red shifted spectrum. This confirms that, in addition to accurately reproducing properties governing molecular adhesion and detachment dynamics as shown in previous work, a good reproduction of spectroscopic features also benefits from the tailored description provided by QMD-FF.