Full Breakdown
Korean Research Team Unveils Water's Liquid-Liquid Critical Point
3/27/2026, 12:21:22 PM
Breakthrough Discovery in Water Research
A research team from Pohang University of Science and Technology (POSTECH), led by Professor Kyung Hwan Kim, has made a significant breakthrough by experimentally identifying the liquid-liquid critical point of water. This discovery, published in the journal *Science* on March 26, 2023, resolves a decades-long scientific debate regarding the unique properties of water, particularly its behavior at cryogenic temperatures. Collaborating with Professor Anders Nilsson from Stockholm University, the team utilized the Pohang 4th generation synchrotron radiation facility to conduct their experiments.
The Nature of Water's Unique Properties
Water is known for its unusual characteristics, such as being densest at 4°C and becoming less dense as it cools further. This behavior is attributed to the existence of two distinct liquid phases: high-density water and low-density water. The critical point, identified at approximately -60°C, marks the temperature at which these two phases merge into one. This finding is crucial for understanding various natural phenomena influenced by water's properties, including climate change and biological processes.
Methodology and Experimental Challenges
The research team faced significant challenges in observing supercooled water, which freezes almost instantaneously at low temperatures. To overcome this, they created non-frozen water at temperatures as low as -70°C by momentarily melting amorphous ice using infrared lasers. The Pohang facility's advanced capabilities allowed them to measure the properties of this fleeting liquid, providing insights into its molecular structure and density under varying pressures and temperatures.
Official Statements & Responses
Professor Kim emphasized the importance of this achievement, stating, "This study has brought a conclusion to the long-standing debate over the 'liquid-liquid critical point.'" He noted that this research will serve as a new starting point for understanding the role of water in various scientific fields. Gu Hyukchae, the 1st Vice Minister of Science and ICT, highlighted the significance of sustained investment in basic research, asserting that it leads to world-class achievements.
Criticism & Opposition
While the findings are celebrated, some experts caution that the assumptions made during the experiments, particularly regarding the equilibrium state of the liquid, may need further validation. Greg Kimmel, a physicist at Pacific Northwest National Laboratory, noted that the rapid measurement techniques used could potentially overlook critical dynamics.
Verbatim Quotes
- “Professor Kim stated, "This is an achievement that can put a period on the long-standing academic debate surrounding water.” — Professor Kyung Hwan Kim, POSTECH
- “I want to continue conducting research worthy of being in textbooks in the future.” — Yoo Seon-joo, Ph.D. candidate, POSTECH
- “It’s amazing that it finally came.” — Nicolas Giovambattista, physicist, Brooklyn College
What's Next
The implications of this discovery extend beyond theoretical discussions; it is expected to enhance the accuracy of research across various disciplines, including life sciences and environmental studies. The POSTECH team plans to continue exploring the properties of water, potentially leading to further groundbreaking discoveries.
