Electric-Field-Induced Ice Crystallization: A Molecular Dynamics Study

The ice crystallization process can be modulated by various external parameters, especially the electric field (Efield). In this study, the influence of the Efield on ice crystallization is systematically investigated using molecular dynamics simulations. When the field strength exceeds 2.5 V·nm^-1, homogeneous nucleation can be directly induced, forming cubic ice structures. Through the analysis of nucleation free energy, it is found that the nucleation free energy barrier gradually decreases with the increasing field strength, which eventually leads to a spontaneous nucleation process. In 10.0 V·nm^-1 field strength, the ice crystallization process exhibits the highest nucleation rate. However, when the field strength exceeds 20.0 V·nm^-1, we observe a counterintuitive decrease in nucleation rates. This phenomenon can be attributed to excessive molecular polarization, which disrupts the balance required for efficient ice nucleus formation. On the other hand, in heterogeneous nucleation, because of the molecular polarization, the Efield also first disrupts the existing ice nuclei, subsequently leading to the formation of new ice nuclei oriented along the Efield direction. This research not only deepens our understanding of the microscopic mechanism of electric-field-induced ice crystallization but also provides theoretical guidance for controlling water crystallization behavior through the Efield in industrial applications.