Simulation of Crystallization of Pentacene and Its Derivatives from Solution

Abstract

The order-emerging stage of crystallization in solution of pentacene and its derivatives was investigated using molecular dynamics simulations. Spontaneous formation of the layered herringbone motif of the pentacene crystal was successfully demonstrated starting from a random mixed solution state. Moreover, I found that the formation of the layer order and the in-layer herringbone-order occurred simultaneously in my simulation because the formation of the layer was driven by the edge-to-face (herringbone shape) interaction between pentacene molecules. This is markedly different from the stepwise order formation from the liquid-crystal-like layer order to the subsequent in-layer herringbone order in the corresponding simulation of the dialkylated pentacene derivative 2,9-dioctyl-pentacene. I also demonstrated the change in the crystal motif from herringbone for pentacene to face-to-face π-stacking for the dechlorinated pentacene derivative 6,13-dichloropentacene because of the steric effect of substituted chlorines disabling the edge-to-face intermolecular interaction in nonsubstituted pentacene.

Impact of Nanoscale Morphology on Charge Carrier Delocalization and Mobility in an Organic Semiconductor

“…Standard intramolecular and Van der Waals interactions of the general AMBER force field [ 25 ] (GAFF) were used to model pentacene, which have been well used and justified in a number of studies. [ 26–32 ] Electrostatic interactions were modeled by restrained electrostatic potential [ 33 ] (RESP) partial charges obtained from B3LYP level of theory using a 6‐311g(d) basis set. The melt‐quench simulations were carried out with the LAMMPS molecular dynamics package [ 34,35 ] employing the particle‐particle‐particle‐mesh Ewald method for calculation of the electrostatic interactions.…”

Simulation of Crystal Nuclei at the Liquid-Air Interface toward Morphology Control via Surface Tension

“…As a comparison, molecular dynamics (MD) simulation is good at computing thermodynamic observables of time-evolving processes while providing microscopic insights, making it an ideal tool for revealing the role of surface tension in crystallization. Although MD simulation has been extensively used to examine organic crystallization from the air or solutions, − few studies have focused on interfacial crystallization in systems with an explicit liquid-air interface. − These systems were designed to simulate the nonequilibrium process of solvent evaporation, during which thermodynamic analysis is challenging. Therefore, it is crucial to design an equilibrium system that represents the key steps of crystallization.…”

Crystalline Behavior of Paraffin Wax

“…Molecular dynamics simulation provides the capability of revealing both the structural and dynamic details on the atomic scale, which is complementary to the experimental research. − For example, Glova et al chose n-eicosane as the paraffin model, and they further evaluated the performance of 10 different force fields in describing the physical properties of n-eicosane . Papavasileiou et al and Shahruddin et al mainly evaluated the performance of the coarse-grained force field in describing the physical properties of n-alkane with different carbon atom numbers, and their binary or multicomponent mixture. , Gan et al and Chen et al studied the influence of paraffin crystal (n-alkane binary mixture) on the viscosity of crude oil and the dynamics properties of other molecules. − Zeng et al explored the mechanism of crystallization behavior of the n-alkane binary mixtures (C 20 and C 30 ) and the influence of the crystal morphology on thermal conductivity .…”