Following the Nucleation Reaction of Gyroid

In nature, block copolymers form mesophases that are useful in a variety of areas, including photonics, drug release, solar cells, and data storage. The gyroid is both one of the most interesting mesophases and the most difficult to nucleate because it has such a weak first order transition. Here we use molecular dynamics simulations with a model binary mixture of mesogenic nanoparticles to determine the transition state and explore the driving forces behind nucleation. We simulated the spontaneous formation of gyroid and tested the efficiency of a number of order parameters as reaction coordinates. Using Aimless Shooting and Maximum Likelihood Optimization, we find that all of the proposed order parameters are able to distinguish the fully-formed gyroid from the liquid, but they are poor reaction coordinates to identify the transition state. However, in this work, we were able to characterize the transition state by using committor analysis methods.