All ground state and excited state DFT & TDDFT calculations of both asphaltene monomers and dimer were carried out with the GPU accelerated quantum chemistry package TeraChem. The DFT ground state geometry optimizations of asphaltene monomers and the constructed dimers were carried out at the wB97X-D3 78 /6-31G* level with the D3 dispersion correction. The molecular coordinates were minimized in the translation rotation internal coordinates (TRIC) until the energy change was within 1×10 -6 Hartree and the maximum displacement within 1.8×10 -3 Å.