Formation Onset of Flat-Perylene Prenucleation Clusters in Vacuum

Abstract

Our current understanding of the prenucleation processes involved in the growth of perylene-based organic nanocrystals is still limited. In this study, we utilized molecular dynamics simulations, employing various flat perylene molecules, to investigate these processes. Our findings reveal that, while cluster formation is primarily driven by molecular aggregation, the Ostwald ripening phenomenon also occurs in a vacuum environment. The presence of a methoxy group influences both the rate and structure of clustering. Interestingly, the preferred initial clusters, as determined by their molar Gibbs free energies, do not align with the crystal units or nuclei observed in herringbone perylene crystals. Overall, this study enhances the understanding of organic nanocrystal formation, specifically nonclassical nucleation pathways, and guides the manipulation of perylene-based organic crystals.