Fixed-Charge Atomistic Force Fields for Molecular Dynamics Simulations in the Condensed Phase: An Overview.

Area of Science:

• Computational chemistry and molecular modeling.
• Biophysics and structural biology.

Background:

• Molecular simulations rely on force fields to model particle interactions.
• Classical fixed-charge force fields, established in 1969, simplify calculations by omitting explicit polarization.
• This simplification significantly reduces computational cost compared to polarizable models and quantum chemistry.

Purpose of the Study:

• To provide an overview of major fixed-charge force field families for (bio)molecular simulations.
• To highlight the historical development and continuous improvements of these force fields.
• To serve as an introductory resource for new researchers in the field.

Main Methods:

• Review and comparison of four major fixed-charge force field families: AMBER, CHARMM, GROMOS, and OPLS.
• Analysis of the classical functional form underlying these force fields.
• Discussion of the implications of fixed-charge approximations in simulations.

Main Results:

• Fixed-charge force fields, despite not modeling polarization, have proven effective for biological and chemical simulations.
• These force fields are continuously refined and remain relevant for modern research.
• The four major families share a common classical functional form but have distinct parameterizations and applications.

Conclusions:

• Fixed-charge force fields represent a computationally efficient approach for molecular simulations.
• Careful parameterization enables these models to yield significant insights into complex systems.
• Understanding the evolution and characteristics of AMBER, CHARMM, GROMOS, and OPLS is crucial for effective (bio)molecular modeling.