(346bu) Understanding the Homogeneous Ice Nucleation Process for Different Ice Polymorphs

Water is perhaps the most ubiquitous molecule on Earth and because of its features, it may exhibit various polymorphic structures each of which strongly depend on the thermodynamic conditions applied during nucleation. However, nucleation is complicated to observe both in experiment and computational work as it is considered to be a rare event. To undergo nucleation, a liquid is cooled down below its melting point reaching a metastable state. Using molecular dynamics simulations, we navigate the phase diagram of the TIP4P/Ice model to improve our understanding of the nucleation process under different temperatures and pressures. Moreover, molecular dynamics allow for the analysis of local order using parameters, such as the tetrahedral order parameter, to characterize polymorphic transformations (hexagonal ice and ices II through V). Because homogeneous ice nucleation often is a result of the competition between local density fluctuations and hydrogen bond formations we also monitor these features throughout the simulations.