TY - JOUR

T1 - Precise simulation of criticality in asymmetric fluids

AU - Orkoulas, G.

AU - Fisher, Michael E.

AU - Panagiotopoulos, Athanassios Z.

PY - 2001

Y1 - 2001

N2 - Extensive grand canonical Monte Carlo simulations have been performed for the hard-core square-well fluid with interaction range (Formula presented) The critical exponent for the correlation length has been estimated in an unbiased fashion as (Formula presented) via finite-size extrapolations of the extrema of properties measured along specially constructed, asymptotically critical loci that represent pseudosymmetry axes. The subsequent location of the critical point achieves a precision of five parts in (Formula presented) for (Formula presented) and about 0.3% for the critical density (Formula presented) The effective exponents (Formula presented) and (Formula presented) indicate Ising-type critical-point values to within 2% and 5.6%, respectively, convincingly distinguishing the universality class from the “nearby” XY and (Formula presented) (self-avoiding walk) classes. Simulations of the heat capacity (Formula presented) and (Formula presented) where (Formula presented) is the vapor pressure below (Formula presented) suggest a negative but small Yang-Yang anomaly, i.e., a specific-heat-like divergence in the corresponding chemical potential derivative (Formula presented) that requires a revision of the standard asymptotic scaling description of asymmetric fluids.

AB - Extensive grand canonical Monte Carlo simulations have been performed for the hard-core square-well fluid with interaction range (Formula presented) The critical exponent for the correlation length has been estimated in an unbiased fashion as (Formula presented) via finite-size extrapolations of the extrema of properties measured along specially constructed, asymptotically critical loci that represent pseudosymmetry axes. The subsequent location of the critical point achieves a precision of five parts in (Formula presented) for (Formula presented) and about 0.3% for the critical density (Formula presented) The effective exponents (Formula presented) and (Formula presented) indicate Ising-type critical-point values to within 2% and 5.6%, respectively, convincingly distinguishing the universality class from the “nearby” XY and (Formula presented) (self-avoiding walk) classes. Simulations of the heat capacity (Formula presented) and (Formula presented) where (Formula presented) is the vapor pressure below (Formula presented) suggest a negative but small Yang-Yang anomaly, i.e., a specific-heat-like divergence in the corresponding chemical potential derivative (Formula presented) that requires a revision of the standard asymptotic scaling description of asymmetric fluids.

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U2 - 10.1103/PhysRevE.63.051507

DO - 10.1103/PhysRevE.63.051507

M3 - Article

C2 - 11414909

AN - SCOPUS:0035333292

SN - 1063-651X

VL - 63

JO - Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics

JF - Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics

IS - 5

ER -