The vanishing limit of the square-well fluid: the adhesive hard sphere model as a reference system

J. Largo; M. A. Miller; F. Sciortino

doi:10.1063/1.2883696

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arXiv · 0712.2934

The vanishing limit of the square-well fluid: the adhesive hard sphere model as a reference system

J. Largo·M. A. Miller·F. Sciortino

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Abstract

We report a simulation study of the gas-liquid critical point for the square-well potential, for values of well width delta as small as 0.005 times the particle diameter sigma. For small delta, the reduced second virial coefficient at the critical point B_2*c is found to depend linearly on delta. The observed weak linear dependence is not sufficient to produce any significant observable effect if the critical temperature T_c is estimated via a constant B_2*c assumption, due to the highly non linear transformation between B_2*c and T_c. This explains the previously observed validity of the law of corresponding states. The critical density rho_c is also found to be constant when measured in units of the cubed average distance between two bonded particles (1+0.5 delta)/sigma. The possibility of describing the delta -> 0 dependence with precise functional forms provides improved acccurate estimates of the critical parameters of the adhesive hard-sphere AHS model.

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J. Largo, M. A. Miller, F. Sciortino. 2007-12-18. The vanishing limit of the square-well fluid: the adhesive hard sphere model as a reference system. https://doi.org/10.1063/1.2883696

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