First-principles many-body force fields from the gas phase to liquid: a "universal" approach
Jesse G McDaniel1, J R Schmidt
1Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States.
The Journal of Physical Chemistry. B
|March 25, 2014
Summary
We developed physically-motivated force fields including three-body interactions for accurate simulations. These force fields are transferable across phases and conditions, improving condensed-phase simulations.
Area of Science:
- Computational chemistry
- Physical chemistry
- Materials science
Background:
- Accurate molecular simulations require robust force fields.
- Existing methods often lack transferability between gas and condensed phases.
- Nonadditive interactions are crucial for condensed-phase accuracy.
Purpose of the Study:
- To develop physically-motivated force fields with explicit three-body terms.
- To achieve transferability from gas-phase to condensed-phase simulations.
- To validate the force fields' accuracy for organic liquids.
Main Methods:
- Extended symmetry-adapted perturbation theory for force field generation.
- Incorporated Axilrod-Teller-Muto-type three-body exchange and dispersion terms.
- Applied the method to six diverse organic liquids/fluids.
Main Results:
- Three-body interactions significantly impact condensed-phase internal pressure.
- The developed force fields show high accuracy for structural, thermodynamic, and dynamic properties.
- No additional parametrization was needed for the three-body terms.
Conclusions:
- Explicit three-body terms are essential for ab initio force field development.
- The new force fields demonstrate excellent transferability across temperatures, pressures, and chemical systems.
- These force fields are widely applicable for condensed-phase simulations.
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