A Transferable Polarizable Force Field for Urea Crystals and Aqueous Solutions
Kyeong-Jun Jeong1, Jesse G McDaniel2, Arun Yethiraj1
1Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States.
The Journal of Physical Chemistry. B
|August 14, 2020
Summary
This study introduces a new polarizable force field for urea, improving predictions of its behavior in water and crystals. This advanced model enhances understanding of urea
Area of Science:
- Computational Chemistry
- Chemical Physics
- Materials Science
Background:
- Urea is a vital chemical with diverse biological and industrial uses.
- Accurate modeling of urea's interactions is crucial for understanding its behavior in solutions and crystals.
Purpose of the Study:
- To develop a first-principles polarizable force field for urea crystals and aqueous solutions.
- To improve the accuracy of molecular simulations involving urea.
Main Methods:
- Utilized the symmetry-adapted perturbation theory (SAPT) protocol with the SWM4-NDP water model.
- Modified the SAPT force field by augmenting urea's carbonyl oxygen, reducing urea's polarizability, and refitting atomic parameters.
- Validated against experimental data and first-principles molecular dynamics simulations.
Main Results:
- The developed polarizable force field accurately predicts static and dynamic properties of aqueous urea solutions.
- The model successfully reproduces the urea crystal-solution phase diagram between 261 K and 310 K.
- The polarizable model demonstrates superior performance compared to non-polarizable models.
Conclusions:
- The new force field provides a reliable tool for simulating urea in various environments.
- This model is expected to advance studies on complex biomolecular systems and the phase behavior of fluids.
- Highlights the importance of polarizability in accurately modeling urea's solid-liquid phase behavior.
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