The team at KRISS subjected water samples to pressures exceeding millions of atmospheres and captured their crystallisation dynamics at micro-second intervals. They discovered Ice XXI—a crystalline phase distinct from all previously characterised 19 known ice polymorphs. Its lattice geometry and bonding suggest that under such conditions hydrogen bonds and oxygen frameworks reorganise in unexpected ways, altering thermal and electrical conductivity.
Planetary scientists say this finding could revise models of internal structure and heat transport in bodies like Europa, Ganymede and Titan, and even certain exoplanets. The discovery underscores that even “simple” water contains complex behaviour under extreme conditions. Future work will explore whether Ice XXI can be stabilised or synthesised in bulk and what its physical properties mean for Earth’s deep geology and beyond.
EXTREME-PRESSURE EXPERIMENT REVEALS “ICE XXI” — A New Phase of Water With Planetary Implications
