My friends in a Cryo-EM lab freeze their very samples quickly, a process they call vitrification. The timescale for this process is milliseconds (from wikipedia):
The production of amorphous ice hinges on the fast rate of cooling. Liquid water must be cooled to its glass transition temperature (about 136 K or −137 °C) in milliseconds to prevent the spontaneous nucleation of crystals.
To me, that seems slow. I suspected that the spontaneous nucleation of water should be much faster then milliseconds based off of the following (obviously erroneous argument): at neutral pH the protonation rate is about a millisecond but this exchange happens very frequently throughout the liquid and once a nucleation event starts it should proceeded exponentially.
Question: What is a good Fermi estimate and explanation for the millisecond timescale of liquid to ice nucleation?
