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Pressure Dependence of Fragile-to-Strong Transition and a Possible Second Critical Point in Supercooled Confined Water

Li Liu·Sow-Hsin Chen·Antonio Faraone·Chun-Wan Yen·Chung-Yuan Mou
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Abstract

By confining water in nano-pores of silica glass, we can bypass the crystallization and study the pressure effect on the dynamical behavior in deeply supercooled state using neutron scattering. We observe a clear evidence of a cusp-like fragile-to-strong (F-S) dynamic transition. Here we show that the transition temperature decreases steadily with an increasing pressure, until it intersects the homogenous nucleation temperature line of bulk water at a pressure of 1600 bar. Above this pressure, it is no longer possible to discern the characteristic feature of the F-S transition. Identification of this end point with the possible second critical point is discussed.

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Li Liu, Sow-Hsin Chen, Antonio Faraone, Chun-Wan Yen, Chung-Yuan Mou. 2005-08-16. Pressure Dependence of Fragile-to-Strong Transition and a Possible Second Critical Point in Supercooled Confined Water. https://doi.org/10.1103/physrevlett.95.117802

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