Effect of bond length fluctuations on crystal nucleation of hard bead chains

TL;DR

This study investigates how bond length fluctuations influence crystal nucleation in bead chains, revealing that nucleation rates depend mainly on the number of bonds, and that adding monomers can enhance crystallization.

Contribution

Introduces a novel event-driven molecular dynamics simulation method and shows that nucleation rates are primarily affected by bond count rather than chain topology.

Findings

Nucleation rates increase with more bonds per sphere.

Crystal nuclei predominantly contain face-centered cubic structures.

Nuclei exhibit diverse morphologies, including five-fold symmetry.

Abstract

We study the spontaneous nucleation and crystallization of linear and cyclic chains of flexibly connected hard spheres using extensive molecular dynamics simulations. To this end, we present a novel event-driven molecular dynamics simulation method, which is easy to implement and very efficient. We find that the nucleation rates are predominately determined by the number of bonds per sphere in the system, rather than the precise details of the chain topology, chain length, and polymer composition. O ur results thus show that the crystal nucleation rate of bead chains can be enhanced by adding monomers to the system. In addition, we find that the resulting crystal n uclei contain significantly more face-centered-cubic than hexagonal-close-packed ordered particles. More surprisingly, the resulting crystal nuclei possess a range of crystal morphologies including structures with a five-fold symmetry.