Abstract

Nucleation has many implications in science and technology, including metal casting, the assembly of microtubules in cells, and the formation of water droplets in the atmosphere. Because the experimental investigation of dynamical nucleation processes is very difficult, much attention has been paid to atomistic simulation efforts in the last two decades.

However, atomistic simulation studies of nucleation face two major challenges. Firstly, the free energy barrier separating the metastable phase and the stable phase can be very high, making nucleation times much larger than the time scales accessible to molecular dynamics simulations. Secondly, it is highly non-trivial to develop a predictive macroscopic model of nucleation using the microscopic quantities directly obtained from atomistic simulations.

In this talk, I aim to address the aforementioned difficulties. I will first briefly introduce state-of-the-art enhanced sampling methods for atomistic simulations, and their applications to studying homogeneous nucleation. I will then discuss our latest thermodynamic model that links macroscopic theories and atomic-scale simulations and thus provide a simple and elegant framework to verify and extend classical nucleation theory.

[1] B. Cheng, G. A. Tribello, M. Ceriotti, Physical Review B ​ 92​ (18), 180102 (2015). [2] B. Cheng, M. Ceriotti, ​ The Journal of chemical physics ​ 146​ (3), 034106 (2017). [3] B. Cheng, G. A. Tribello, M. Ceriotti, ​ The Journal of chemical physics ​ 147 (10), 104707 (2017). [4] B. Cheng, M. Ceriotti, ​ arxiv: 1803.09140 (2018).