Furthermore, this approach would permit to validate the OPLS-AA and IFF force fields used in MD simulations, as it only depends on the fundamental laws of physics and do not require any previous knowledge on the system under study. Due to the accuracy of DFT calculations, calculating the adsorption energy of the large DCA molecules would be computationally expensive and results difficult to interpret. Therefore, we instead study small molecules containing the same polar motifs as the DCAs adsorbing onto circumovalene in our MD simulations, which are presented in Figure . In order to appropriately sample the conformational space, different initial geometries are modelled for all molecules from Figure , such as monodendate, bidendate or tridendate adsorption for TMA. Moreover, different relative locations of the adsorbate with respect to the carbonaceous deposit are studied to gauge whether adsorption is favoured in the basal PAH plane or next to the circumovalene edge. DFT calculations are performed using the Vienna ab-initio simulation program (VASP) with the projector augmented wave (PAW) formalism. Calculations are performed with the non-local optB86b-vdW exchangecorrelation functional to approximately account for dispersion interactions, which are important to obtain accurate adsorption energies from DFT calculations of organic molecules on various surfaces. The plane-wave cutoff energy is set to 400 eV, with a single k-point in the Γ-position.