The monomer data set. Studying the fluorescence of all 8646 dimers formed from the 132 monomers is infeasible due to the high computational costs. Hence, we focus on a set of representative asphaltene monomers to study the effect of intermolecular configuration on dimer fluorescence: C05, C22, and PC113 (Figure ). We performed an extensive conformation search on two dimers: C22-PC113 and C05-C22. For each dimer, 500 conformers are generated by ABCluster 75 with the general Amber force field (GAFF) as the energy evaluator, followed by the removal of energy deduplicates with energy difference less than 0.005 kcal/mol and the geometric deduplicates with RMSD less than 0.5 Å. The resulting conformers were optimized at the ground and excited states using DFT or TDDFT, and the resulting four geometries with the lowest S1 energy were selected for further analysis.