Insights into water freezing from classical nucleation theory

Area of Science:

• Physical Chemistry
• Materials Science
• Thermodynamics

Background:

• Water freezing is a critical phenomenon with significant applications.
• The theoretical explanation for rapid (nanosecond) water freezing has been lacking.
• Understanding ice nucleation rates is essential for various scientific and industrial processes.

Purpose of the Study:

• To develop a theoretical model explaining the rapid freezing of water.
• To reveal the underlying physics of ice formation at the nanoscale.
• To establish a method for measuring ice nucleation rates.

Main Methods:

• Combined classical nucleation theory with Mie theory.
• Developed a kinetic model to reproduce experimental observations.
• Derived the Zel'dovich-Frenkel (ZF) equation for phase transitions.
• Analyzed experimental and simulation data.

Main Results:

• Successfully reproduced the phenomenon of decreasing transmissivity during rapid freezing.
• Revealed the stages of ice formation: nucleation, growth, and engulfment.
• Identified ice/vacuum interface scattering as a potential cause for transparency changes.
• Established a limit for the phase transition driving force: |Δμ|/(kBT) ≤ 1.
• Found that phase transitions continue post-normalization during rapid processes.
• Developed an approximate formula linking nucleation rate and sample transparency.

Conclusions:

• The developed kinetic model provides the first theoretical explanation for rapid water freezing phenomena.
• The study offers insights into phase transition kinetics, applicable to other materials.
• The derived formula enables prediction of transparency changes and measurement of nucleation rates.