Parametrization and Validation of Intramolecular Force Fields Derived from DFT Calculations

Area of Science:

• Computational Chemistry
• Molecular Modeling
• Materials Science

Background:

• Accurate molecular simulations require reliable force fields.
• Parametrizing force fields from quantum mechanical calculations is computationally intensive.
• Existing methods may not adequately capture the behavior of flexible molecules.

Purpose of the Study:

• To develop a systematic procedure for parametrizing intramolecular force fields.
• To enable accurate computer simulations using density functional theory (DFT) data.
• To validate the method for various molecular models, including united atom and coarse-grained approaches.

Main Methods:

• Utilizing energy and its first and second geometrical derivatives from DFT calculations.
• Applying the method to multiple molecular conformations.
• Performing molecular dynamics simulations for validation.

Main Results:

• Successfully parametrized intramolecular force fields for diverse molecules.
• Demonstrated the method's applicability to atomistic, united atom, and coarse-grained models.
• Validated simulation results against literature force fields and experimental data.

Conclusions:

• The proposed DFT-based parametrization method provides accurate intramolecular force fields.
• The approach is versatile, applicable to different levels of molecular representation.
• It shows particular promise for simulating flexible molecules with soft torsional potentials, preserving chemical specificity.