Polarizable coarse-grained models for molecular dynamics simulation of liquid cyclohexane
Oliwia M Szklarczyk1, Eirini Arvaniti1, Wilfred F van Gunsteren1
1Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology ETH, 8093, Zürich, Switzerland.
Abstract:
Force field parameters for polarizable coarse-grained (CG) supra-atomic models of liquid cyclohexane are proposed. Two different bead sizes were investigated, one representing two fine-grained (FG) CH(2)r united atoms of the cyclohexane ring, and one representing three FG CH(2)r united atoms. Electronic polarizability is represented by a massless charge-on-spring particle connected to each CG bead. The model parameters were calibrated against the experimental density and heat of vaporization of liquid cyclohexane, and the free energy of cyclohexane hydration. Both models show good agreement with thermodynamic properties of cyclohexane, yet overestimate the self-diffusion. The dielectric properties of the polarizable models agree very well with experiment.
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