NONUNIVERSALITY OF PHASE-SEPARATION IN 2-DIMENSIONAL CRITICAL BINARY-FLUID MIXTURES

The domain growth in the late-time regime of phase-separating two-dime nsional A-B critical fluid mixtures is investigated with molecular-dyn amics simulations. Growth exponents are found to depend not only on te mperature, as was previously shown, but also on the particular pair in teraction potential. We study this dependence for two different molecu lar pair potentials with reduced strength among unequal particles and discuss possible mechanisms for the coarsening process as a function o f temperature. At the low-temperature quenching regime the phase separ ation shows percolating patterns not previously reported, where a sequ ential aggregation of clusters gives rise to a possible multi-scaling behaviour.