The vanishing limit of the square-well fluid: the adhesive hard-sphere model as a reference system.
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 B2*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 Tc is estimated via a constant B2*c assumption, due to the highly nonlinear transformation between B2*c and Tc. 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 cube of the 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 accurate estimates of the critical parameters of the adhesive hard-sphere model.
Largo
J
J
Dipartimento di Fisica, Università di Roma La Sapienza, Piazzale A. Moro 2, 00185 Roma, Italy. largojulio@gmail.com
Miller
M A
MA
Sciortino
F
F
D000268:Adhesiveness; D001665:Binding Sites; D003198:Computer Simulation; D006244:Hardness; D044085:Microfluidics / Q000379:methods*; D008956:Models, Chemical; D008968:Molecular Conformation; D011485:Protein Binding; D011506:Proteins / Q000737:chemistry*
D011506:Proteins