Coarse-grained electrostatic interactions of coronene: Towards the crystalline phase

Area of Science:

• Computational chemistry
• Materials science
• Molecular modeling

Background:

• Accurate modeling of electrostatic interactions is crucial for understanding molecular behavior.
• Previous work established an anisotropic effective potential for van der Waals forces in coronene.
• Disc-shaped aromatic molecules like coronene exhibit complex electrostatic interactions.

Purpose of the Study:

• To present and compare two coarse-grained approaches for modeling electrostatic interactions in coronene.
• To introduce electrostatic components to existing anisotropic potentials.
• To validate these models using molecular dynamics simulations.

Main Methods:

• Systematic coarse-graining from atomistic to mesoscopic scales.
• Development of two electrostatic models: linear quadrupole and ring-like charge distribution.
• Reparameterization of an effective Gay-Berne-like potential.
• Many-particle molecular dynamics simulations of coronene in the karpatite phase.

Main Results:

• The second approach, accounting for ring-like charge distribution, showed good agreement with experimental data.
• Simulations focused on crystalline phase (karpatite) to assess electrostatic effects on tilted stacked columns.
• Structural parameters and melting transitions were investigated.

Conclusions:

• The ring-charge distribution model provides a reliable method for simulating electrostatic interactions in coronene.
• This coarse-grained strategy is transferable to other disc-shaped aromatic molecules.
• Despite limitations in large-distance decay, the second model's accuracy is demonstrated.