A First Principles Development of a General Anisotropic Potential for Polycyclic Aromatic Hydrocarbons

Area of Science:

• Computational chemistry
• Materials science
• Chemical physics

Background:

• Standard atom-atom potentials fail to accurately describe polycyclic aromatic hydrocarbon (PAH) binding configurations in clusters.
• The primary limitation of existing potentials is their lack of anisotropy, failing to capture directional interactions.

Purpose of the Study:

• To develop a novel anisotropic atom-atom intermolecular potential for modeling interactions between PAH molecules.
• To create a transferable potential applicable to various PAH systems and configurations.

Main Methods:

• Constructed an anisotropic potential for benzene using first-principles symmetry-adapted perturbation theory based on density functional theory (SAPT(DFT)).
• Employed interaction energy calculations and the Williams-Stone-Misquitta method for distributed molecular properties.

Main Results:

• The developed anisotropic potential accurately models interaction energies for diverse dimer configurations of four different PAH molecules.
• This new potential outperforms standard isotropic potentials, particularly for configurations poorly described previously.

Conclusions:

• The newly developed transferable anisotropic potential offers a significant improvement for modeling PAH intermolecular interactions.
• This work provides a foundation for future research into the aggregation behavior of polycyclic aromatic hydrocarbons.