Scientists found ice with a 304-molecule repeating pattern
Boing Boing • • technology
Key Points:
- Researchers have identified two new complex phases of ice, ice XXI and ice XXII, expanding the known catalog of over 20 distinct water crystalline forms.
- The discovery originated from a 2018 experiment at KRISS where water under pressure exhibited an unidentified intermediate state, later investigated using the European X-Ray Free-Electron Laser in 2025.
- Ice XXI features a repeating molecular structure of 152 molecules, while ice XXII has an even larger repeating pattern of 304 molecules, marking them as the most structurally complex ice phases found.
- These findings support Ostwald's step rule, which posits that matter under pressure transitions through intermediate phases before reaching stability.
- Understanding these ice phases has practical implications, such as preventing unwanted phase shifts in pharmaceutical drug crystals that can compromise manufacturing.
