Vapor–liquid equilibrium, fluid state, and zero-pressure solid properties of chlorine from anisotropic interaction potential by molecular dynamics

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Extensive examination of the anisotropic interaction potential of chlorine by Rodger et al. [P.M. Rodger, A.J. Stone, D.J. Tildesley, J. Chem. Soc., Faraday Trans. 2, 83 (1987) 1689–1702] (with interaction sites located at the positions of atoms in a molecule and the electrostatic part found by ab initio calculations) for its predictive power has been performed. We have calculated (i) the second virial coefficient by using a non-product algorithm, (ii) a series of liquid-phase state points in the temperature and pressure ranges of 200 to 400 K and 0 to 6.2 MPa, respectively, by the constant pressure–constant temperature molecular dynamics simulations, (iii) vapor–liquid equilibrium and heat of vaporization from the triple point (172 K) to 300 K by the Gibbs–Duhem integration method combined with simultaneous (but independent) constant pressure–constant temperature molecular dynamics simulations of the vapor and liquid phases, and (iv) the properties of the zero-pressure crystal structures by molecular dynamics technique due to Parinello and Rahman [M. Parrinello, A. Rahman, Phys. Rev. Lett. 45 (1980) 1196–1199]. Generally, good to excellent agreement of the calculated properties with the corresponding values for real chlorine was observed. The results obtained from the investigated interaction potential are equivalent to (or even better than) those reported for a more complicated potential by Wheatley and Price [R.J. Wheatley, S.L. Price, Mol. Phys. 71 (1990) 1381–1404].