Thermodynamics and Dynamics of the Two-Scale Spherically-Symmetric Jagla Model of Anomalous Liquids

Details Thermodynamics and Dynamics of the Two-Scale Spherically-Symmetric Jagla Model of Anomalous Liquids Thermodynamics and Dynamics of the Two-Scale Spherically-Symmetric Jagla Model of Anomalous Liquids

2006-05-02

arxiv.org/abs/cond-mat/0605074v1

Phys. Rev. E 74, 031108 (2006)

Physics

Condensed Matter

Soft Condensed Matter

9 pages, 18 figures

Scientific paper

10.1103/PhysRevE.74.031108

Using molecular dynamics simulations, we study a liquid model which consists of particles interacting via a spherically-symmetric two-scale Jagla ramp potential with both repulsive and attractive ramps. The Jagla potential displays anomalies similar to those found in liquid water, namely expansion upon cooling and an increase of diffusivity upon compression, as well as a liquid-liquid (LL) phase transition in the region of the phase diagram accessible to simulations. The LL coexistence line, unlike in tetrahedrally-coordinated liquids, has a positive slope, because of the Clapeyron relation, corresponding to the fact that the high density phase (HDL) is more ordered than low density phase (LDL). When we cool the system at constant pressure above the critical pressure, the hydrodynamic properties rapidly change from those of LDL-like to those of HDL-like upon crossing the Widom line. The temperature dependence of the diffusivity also changes rapidly in the vicinity of the Widom line, namely the slope of the Arrhenius plot sharply increases upon entering the HDL domain. The properties of the glass transition are different in the two phases, suggesting that the less ordered phase (LDL) is fragile, while the more ordered phase (HDL) is strong, which is consistent with the behavior of tetrahedrally-coordinated liquids such as water silica, silicon, and BeF$_2$.

Affiliated with

Also associated with

No associations

Rating

Thermodynamics and Dynamics of the Two-Scale Spherically-Symmetric Jagla Model of Anomalous Liquids does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Thermodynamics and Dynamics of the Two-Scale Spherically-Symmetric Jagla Model of Anomalous Liquids, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Thermodynamics and Dynamics of the Two-Scale Spherically-Symmetric Jagla Model of Anomalous Liquids will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-307115