Supercooled systems phase transitions

We have carried out MD simulations for the 3-d binary soft-sphere model with N=500 atoms in a cubic cell. First, we have simulated a liquid equilibrium at Feff = 0.8 then with using the configuration at the final step of this run, the system was quenched down to Teff = 1.50 (quenching process) followed by annealing MD simulation at this Fefr over ten million time steps. This Feg- is still lower than Fj (=1.58, the glass transition), but slightly higher than F (=1.45, kinetic transition) in the supercooled fluid phase. 

In a first order phase transition, thermodynamic functions by definition discon-tinuously change as one cools the system along a path crossing the equilibrium coexistence line (Fig. 5a, path j8). In a rea/experiment, however, this discontinuous change may not occur at the coexistence line because a substance can remain in a supercooled metastable phase until a limit of stability (a spinodal) is reached [2] (Fig. 5b, path fi). 

Fig. 2.8 a A schematic of a double welled potential. At high temperatures both wells can be sampled. As the temperature reduces the deeper, low density well becomes the preferentially filled, resulting in a LDL. As the pressure is increased the system becomes situated in the less deep well, corresponding to a higher density liquid, b The proposed position in TP space of the liquid-liquid phase transition in water, reproduced from Mishima and Stanley (Reprinted by permission from Macmillan Publishers Ltd [48], 1998). Th is the homogenous nuclea-tion temperature line for supercooled water, while Tx is the temperature at which amorphous ice spontaneously crystallizes upon heating... 

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