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Continuous and Discontinuous Dynamic Crossover in Supercooled Water in Computer Simulations

[Image: see text] The dynamic crossover behavior of supercooled water as described by the first-principle based WAIL potential was investigated. Below the second liquid–liquid critical point, the viscosity shows a discontinuous jump consistent with a first-order phase transition between the high den...

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Detalles Bibliográficos
Autores principales: Ma, Zhonghua, Li, Jicun, Wang, Feng
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2015
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4565576/
https://www.ncbi.nlm.nih.gov/pubmed/27476514
http://dx.doi.org/10.1021/acs.jpclett.5b01348
Descripción
Sumario:[Image: see text] The dynamic crossover behavior of supercooled water as described by the first-principle based WAIL potential was investigated. Below the second liquid–liquid critical point, the viscosity shows a discontinuous jump consistent with a first-order phase transition between the high density liquid and the low density liquid. Above the critical point, a continuous transition occurs with only the first derivative of viscosity being discontinuous, and the dynamic crossover temperature is about 8 K below the thermodynamic switchover temperature. The 8 K shift can be explained by a delay in dynamic crossover, which does not occur until the more viscous liquid starts to dominate the population and jams the flow. On the basis of finite-size effects observed in our simulations, we believe that dynamic discontinuity may be observable above the critical point in confined water when the confinement is on a length scale shorter than the spatial correlation.