(551c) Accessing the Inaccessible: Studying the Liquid-to-Solid Transition in Molecular Simulations

Nucleation – that is the onset of a new phase from a metastable phase – is a difficult phenomenon to study both experimentally and computationally. Nucleation relevant spatial and temporal resolution is difficult to access in experiments. In contrast, while computer simulations are perfectly suited to probe these length and timescales, sampling statistical number of nucleation events is computationally expensive. In our research, we use advanced sampling techniques in conjunction with molecular dynamics simulations to sample hundreds and thousands of nucleation events. We apply these methods to study liquid-to-solid phase transitions in Lennard-Jones systems, water and aqueous solutions. In my talk, I will discuss key results obtained for homogeneous nucleation in Lennard-Jones-like liquids and in aqueous solutions. The latter specifically focuses on nucleation of clathrate hydrates of water soluble guest molecules. I will also discuss the limitations of the current methodologies and our approaches to improve the efficiency of the advanced sampling techniques. We have developed novel sampling methods that have the potential to be more efficient in sampling rare events thereby, making studies of phenomena such as nucleation more viable and accessible.