PCMRESP: A Method for Polarizable Force Field Parameter Development and Transferability of the Polarizable Gaussian...

Area of Science:

• Computational Chemistry
• Molecular Modeling
• Physical Chemistry

Background:

• Transferability of force field parameters is essential for developing accurate molecular models.
• Previous studies confirmed electrostatic parameter transferability from polarizable Gaussian multipole models (pGMs) in various systems.
• Developing robust polarizable force fields requires reliable electrostatic parametrization methods.

Purpose of the Study:

• Introduce PCMRESP, a novel method for electrostatic parametrization in solution for polarizable force fields.
• Assess the transferability of fixed charge and two polarizable Gaussian multipole (pGM) models.
• Evaluate the performance of these models across diverse molecules and solvent environments.

Main Methods:

• Utilized the novel PCMRESP method for electrostatic parametrization.
• Tested three models: fixed charge, pGM with induced polarization, and pGM with permanent and induced polarization.
• Evaluated models on 377 small molecules and 100 tetra-peptides in five dielectric environments (gas, diethyl ether, dichloroethane, acetone, water).
• Assessed transferability using dual-solvent strategies and compared with the traditional HF/6-31G* method.

Main Results:

• Atomic polarization significantly enhances electrostatic parameter transferability.
• Incorporating permanent atomic dipoles (covalent bond dipoles) further improves transferability.
• Dual-solvent strategies demonstrate consistent transferability across all tested models.
• The traditional HF/6-31G* method showed poor transferability for pGM models.

Conclusions:

• PCMRESP facilitates the development of highly transferable polarizable force fields.
• Polarization and permanent atomic dipoles are critical for robust electrostatic modeling.
• The dual-solvent approach offers a reliable strategy for assessing parameter transferability.
• Conventional methods like HF/6-31G* may be limited for developing transferable electrostatic models.