Liu Li, Chen Sow-Hsin, Faraone Antonio, Yen Chun-Wan, Mou Chung-Yuan
Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Phys Rev Lett. 2005 Sep 9;95(11):117802. doi: 10.1103/PhysRevLett.95.117802.
By confining water in nanopores 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 cusplike fragile-to-strong (FS) 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 FS transition. Identification of this end point with the possible second critical point is discussed.
通过将水限制在石英玻璃的纳米孔中，我们可以绕过结晶过程，并利用中子散射研究深度过冷状态下压力对动力学行为的影响。我们观察到了类尖点的从脆性到强性（FS）动态转变的明确证据。在此我们表明，转变温度随着压力的增加而稳步下降，直到在1600巴的压力下与大块水的均匀成核温度线相交。高于此压力，就不再能够辨别FS转变的特征。讨论了将这个终点与可能的第二个临界点进行识别的问题。
