Overview
- Researchers used ultrafast X-ray laser pulses at South Korea’s PAL-XFEL to capture water’s structure just before it froze.
- By briefly melting amorphous ice, the team probed deeply supercooled liquid that is normally unreachable because it crystallizes too fast.
- The measurements show two distinct liquid forms that merge at a critical point near minus 63 degrees Celsius and about 1,000 atmospheres.
- Molecular motion slowed dramatically near that region, which a researcher compared to a black hole because escape seemed impossible.
- The results, published in Science by an international team led by Stockholm University, point to fluctuations from this critical region as a driver of water’s odd density, heat capacity, and compressibility, with follow-up studies planned across chemistry, biology, geology, and climate.