Dissipative particle dynamics: Systematic parametrization using water-octanol partition coefficients.

Area of Science:

• Computational chemistry
• Molecular dynamics
• Thermodynamics

Background:

• Dissipative particle dynamics (DPD) is a coarse-grained simulation method.
• Accurate parametrization of DPD is crucial for reliable predictions.
• Thermodynamic data, like partition coefficients, are key inputs for DPD models.

Purpose of the Study:

• To develop a systematic, top-down thermodynamic parametrization scheme for DPD.
• To utilize water-octanol partition coefficients, phase equilibria, and density data.
• To demonstrate the feasibility of computing partition coefficients within DPD.

Main Methods:

• A staged optimization scheme was employed for parameter fitting.
• Brute-force simulations were used to compute partition coefficients.
• The methodology was validated against experimental data for 21 small molecules across five chemical classes.

Main Results:

• The parametrization scheme was successfully fitted to experimental partition coefficient data.
• The method demonstrated accuracy for various small molecules including alcohols, amines, ethers, aromatics, and alkanes.
• Transferability of parameters was shown by predicting surfactant properties.

Conclusions:

• The developed DPD parametrization scheme is effective and robust.
• The approach enables accurate prediction of molecular partitioning and thermodynamic behavior.
• This method advances the application of DPD in chemical and materials science.