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.
Journal of Computational Chemistry
|May 28, 2015
Summary
New coarse-grained models for liquid cyclohexane capture thermodynamic and dielectric properties accurately. These polarizable models show good agreement with experimental data, though self-diffusion is overestimated.
Area of Science:
- Computational chemistry
- Molecular modeling
- Physical chemistry
Background:
- Developing accurate coarse-grained (CG) models is crucial for simulating large molecular systems.
- Polarizable force fields are needed to capture electrostatic interactions accurately in condensed phases.
Purpose of the Study:
- To develop and validate polarizable coarse-grained (CG) supra-atomic models for liquid cyclohexane.
- To investigate the effect of bead size on model performance.
Main Methods:
- Proposed force field parameters for CG supra-atomic models of liquid cyclohexane.
- Investigated two bead sizes: representing two or three fine-grained (FG) united atoms.
- Incorporated electronic polarizability using charge-on-spring particles.
- Calibrated model parameters against experimental density, heat of vaporization, and hydration free energy.
Main Results:
- Both CG models demonstrated good agreement with experimental thermodynamic properties of cyclohexane.
- The dielectric properties of the polarizable models closely matched experimental values.
- Self-diffusion coefficients were overestimated by both models.
Conclusions:
- The proposed polarizable CG models offer a good balance between accuracy and computational efficiency for liquid cyclohexane.
- These models are suitable for studying thermodynamic and dielectric properties, but further refinement may be needed for dynamic properties like diffusion.
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