Simple liquid models with corrected dielectric constants.

Area of Science:

• Computational chemistry
• Materials science
• Physical chemistry

Background:

• Explicit-solvent models in molecular simulations can yield inaccurate liquid properties.
• Inaccuracies include density, heat capacity, permittivity, and transfer free energies.
• These limitations have driven the development of complex polarizable solvent models.

Purpose of the Study:

• To develop new fixed-charge solvent models for molecular simulations.
• To improve the accuracy of simulating water, carbon tetrachloride, chloroform, and dichloromethane.
• To offer a more efficient alternative to existing solvent models.

Main Methods:

• Parametrization of fixed-charge solvent models.
• Inclusion of experimental dielectric constants in the parametrization process.
• Evaluation of model performance against experimental liquid properties.

Main Results:

• New fixed-charge models for water, CCl4, CHCl3, and CH2Cl2 were developed.
• Models were parametrized to match experimental dielectric constants, in addition to density and enthalpy of vaporization.
• Improved accuracy was observed for properties like self-diffusion coefficients.

Conclusions:

• Parametrizing fixed-charge solvent models to fit experimental dielectric constants is a promising approach.
• This method offers a potentially more accurate and efficient way to model solvents in computer simulations.
• The developed models show improved predictive power for various liquid properties.