Critical point and phase behavior of the pure fluid and a Lennard-Jones mixture
- Institute for Physical Science and Technology and Department of Chemical Engineering, University of Maryland, College Park, Maryland 20742-2431 (United States)
Monte Carlo simulations in the grand canonical ensemble were used to obtain liquid-vapor coexistence curves and critical points of the pure fluid and a binary mixture of Lennard-Jones particles. Critical parameters were obtained from mixed-field finite-size scaling analysis and subcritical coexistence data from histogram reweighting methods. The critical parameters of the untruncated Lennard-Jones potential were obtained as T{sub c}{sup {asterisk}}=1.3120{plus_minus}0.0007, {rho}{sub c}{sup {asterisk}}=0.316{plus_minus}0.001 and p{sub c}{sup {asterisk}}=0.1279{plus_minus}0.0006. Our results for the critical temperature and pressure are not in agreement with the recent study of Caillol [J. Chem. Phys. {bold 109}, 4885 (1998)] on a four-dimensional hypersphere. Mixture parameters were {epsilon}{sub 1}=2{epsilon}{sub 2} and {sigma}{sub 1}={sigma}{sub 2}, with Lorentz{endash}Berthelot combining rules for the unlike-pair interactions. We determined the critical point at T{sup {asterisk}}=1.0 and pressure-composition diagrams at three temperatures. Our results have much smaller statistical uncertainties relative to comparable Gibbs ensemble simulations. {copyright} {ital 1998 American Institute of Physics.}
- OSTI ID:
- 670198
- Journal Information:
- Journal of Chemical Physics, Vol. 109, Issue 24; Other Information: PBD: Dec 1998
- Country of Publication:
- United States
- Language:
- English
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