Experimental evidence of a liquid-liquid critical point in supercooled water

Science 2026

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Authors: Seonju You, Marjorie Ladd-Parada, Kyeongmin Nam, Aigerim Karina, Sohun Lee, Myoungyoup Shin, Cheolhee Yang, Yeseul Han, Sangmin Jeong, Kichan Park, Kyeongwon Kim, Minjeong Ki
+13 more Robin Tyburski, Iason Andronis, Keely Ralf, Jae Hyuk Lee, Intae Eom, Minseok Kim, Rory Ma, Dogeun Jang, Fivos Perakis, Peter H. Poole, Katrin Amann‐Winkel, Kyung Hwan Kim, Anders Nilsson
DOI: 10.1126/science.aec0018
Cited by: 12
References: 56

Abstract

The search for the liquid-liquid critical point in supercooled water is challenging owing to rapid crystallization. We studied supercooled water at timescales before ice formation by heating high- and low-density amorphous ices using infrared ultrafast laser pulses, followed by x-ray scattering. By varying the pump laser fluence, we accessed liquid states straddling the predicted critical point. We observed a crossover from a discontinuous to a continuous transition at which broad and slow structural variations occurred, consistent with critical fluctuations and slowing down. We also observed a rapid increase in the heat capacity indicating a critical divergence at 210 ± 8 K coincident with enhanced density fluctuations. These results suggest that our experiments have directly probed the vicinity of a critical point in supercooled water.

Fields of Study & Subjects

Material Dynamics and Properties nanoparticles nucleation surface interactions Phase Equilibria and Thermodynamics

Publication details

Journal / source
Science
Publisher
American Association for the Advancement of Science (AAAS)
Volume
391
Issue
6792
Pages
1387–1391
Publication date
26 March 2026
Language
EN