| Autor: |
Moore, Emily B., Molinero, Valeria |
| Předmět: |
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| Zdroj: |
Journal of Chemical Physics; 6/28/2009, Vol. 130 Issue 24, p244505, 12p, 6 Graphs |
| Abstrakt: |
The evolution of the structure of water from the stable high temperature liquid to its glass, low-density amorphous ice (LDA), is studied through large-scale molecular dynamics simulations with the mW model [J. Phys. Chem. B 113, 4008 (2009)]. We characterize the density, translational, and orientational ordering of liquid water from the high temperature stable liquid to the low-density glass LDA at the critical cooling rate for vitrification. A continuous transition to a tetrahedrally ordered low-density liquid is observed at 50 K below the temperature of maximum density and 25 K above a temperature of minimum density. The structures of the low-density liquid and glass are consistent with that of a continuous random tetrahedral network. The liquid-liquid transformation temperature TLL, defined by the maximum isobaric expansivity, coincides with the maximum rate of change in the local structure of water. Long-range structural fluctuations of patches of four-coordinated molecules form in the liquid. The correlation length of the four-coordinated patches in the liquid increases according to a power law in the range 300 K to TLL+10 K; a maximum is predicted at TLL. To the best of our knowledge this is the first direct estimation of the Widom line of supercooled water through the analysis of structural correlations. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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