Growth dynamics of phase separation for two-dimensional binary fluid

Abstract

The dynamics of phase separation in two-dimensional binary fluid with low-middle densities was investigated by molecular dynamics simulation. The spinodal decomposition region for symmetric systems may be divided into the diffusive and kinematic region. At an elevated temperature, the motion of particles is diffusive. At a middle temperature, the kinematic mechanism takes effect on the systems with middle density, and the diffusive mechanism holds only for the dilute system. At a low temperature, the phase separation obeys the kinematic mechanism in a wide range of density. For asymmetric systems, the growth of particles A (majority) is different from that of particles B (minority). The diffusive and kinematic regions for the majority are similar to those of symmetric system. The growth exponent for the minority is related to its absolute density and temperature because of its small density.

Keywords

molecular dynamics / phase separation / binary fluid

References

[1] Siggia E D. Late Stages of Spinodal Decomposition in Binary Mixtures. Phys. Rev. A, 1979, 20(2): 595-605.

[2] Bray A J. Theory of Phase Ordering Kinetics. Adv. Phys., 1994, 43(3): 357-459.

[3] Lifshitz I M, Slyozov V V. The Kinetics of Precipitation from Supersaturated Solid Solutions. J. Phys. Chem. Solids, 1961, 19(1/2): 35-50.

[4] Lookman T, Wu Y, Alexander F J, Chen S. Spinodal Decomposition in Fluids: Diffusive, Viscous, and Inertial Regimes. Phys. Rev. E, 1996, 53(5): 5513-5516.

[5] Furakawa H. Dynamics of Phase Separation of a Simple Fluid Mixture: Comparison between Molecular Dynamics and Numerical Integration of the Phenomenological Equation. Phys. Rev. E, 1997, 55(1): 1150-1161.

[6] Laradji M, Toxvaerd S, Mouritsen O G. Molecular Dynamics Simulation of Spinodal Decomposition in Three-dimensional Binary Fluids. Phys. Rev. Lett., 1996, 77(11): 2253-2256.

[7] Zhang W B, Zou X W. Structure and Growth of the Cluster in Gas-Liquid Transition of Two-dimensional Fluid. Physical A, 1999, 272: 12-21.

[8] Leptoukh G., Strickland B, Roland C. Phase Separation in Two-dimensional Fluid Mixtures. Phys. Rev. Lett., 1995, 74(18): 3636-3639.

[9] Mecke K R, Sofonea V. Morphology of Spinodal Decomposition. Phys. Rev. E, 1997, 56(4): R3761-R3764.

[10] Lach-hab M, Gonzalez A E, Blaisten-Barojas E. Concentration Dependence of Structural and Dynamical Quantities in Colloidal Aggregation: Computer Simulations. Phys. Rev. E, 1996, 54(5): 5456-5462.

[11] Allen M P, Tildesley D J. Computer Simulation of Liquids, 1987 Wuhan: Oxford University Press.

[12] Hoover W G. Canonical Dynamics: Equilibrium Phase-space Distributions. Phys. Rev. A, 1985, 31(3): 1695-1697.

[13] Rovere M, Heermann D W, Binder K. The Gas-Liquid Transition of the Two-dimensional Lennard-Jones Fluid. J. Phys. Condens. Matter, 1990, 2(33): 7009-7032.

[14] Sevick E M, Monson P A, Ottino J M. Monte Carlo Calculations of Cluster Statistics in Continuum Models of Composite Morphology. J. Chem. Phys., 1988, 88(2): 1198-1206.