Crystal lattice properties fully determine short-range interaction parameters for alkali and halide ions

Area of Science:

• Computational chemistry
• Materials science
• Physical chemistry

Background:

• Accurate ion models are crucial for molecular simulations.
• Existing ion force fields often depend on specific water models, limiting transferability.
• Developing transferable ion parameters is a persistent challenge.

Purpose of the Study:

• To present a solvent-independent approach for calibrating ion force field parameters.
• To enable accurate ion modeling across diverse simulation systems.
• To overcome limitations of water-model-dependent parameterization.

Main Methods:

• Calibrating ion parameters using only crystal lattice properties.
• Minimizing lattice sums to calculate lattice energies and interionic distances.
• Simultaneously optimizing parameters for multiple alkali and halide ions under periodic table constraints.

Main Results:

• Developed lattice-derived parameters for primitive and Lennard-Jones models.
• Parameters accurately reproduce crystal lattice properties.
• Lennard-Jones parameters show quantitative agreement with experimental hydration free energies, demonstrating transferability.

Conclusions:

• The proposed method provides transferable ion parameters independent of solvent models.
• This approach is computationally efficient and suitable for various crystallizable ions.
• The derived parameters enhance the reliability of ion simulations in diverse chemical systems.