“…Indeed, a lot of work has been done already, on a variety of classical water models: ST2 [27], TIP4P (in its various declinations) [28][29][30][31][32][33], and monatomic water (mW) [28,31,[34][35][36][37][38][39]. Also the methods employed to investigate ice nucleation have been the most varied: umbrella sampling [27,31,36], seeding approach [28,30,37], mean first passage time [34], metadynamics [32], density-functional theory [40], forward-flux sampling [29,33,38], and aimless shooting [39]. While all studies agree on the main picture (i.e., that the nucleation cluster is polymorphic rather than structurally homogeneous), divergence persists on the critical size, nucleation rate, interface free energy, and importance of the various ice polymorphs in the first stages of crystallization.…”