Evaluation and Optimization of Interface Force Fields for Water on Gold Surfaces.

Area of Science:

• Surface science
• Computational chemistry
• Materials science

Background:

• Water-gold interfaces are critical for applications like lab-on-a-chip and electrowetting.
• Classical molecular dynamics (MD) simulations are widely used for water-gold interface studies.
• The accuracy of MD simulations hinges on the suitability of the chosen force field.

Purpose of the Study:

• To benchmark the accuracy of different force fields for water-gold interactions.
• To evaluate the performance of Lennard-Jones, Morse, and Buckingham potentials.
• To guide the selection of appropriate force fields for future simulations.

Main Methods:

• Density functional theory (DFT) calculations were performed for a single water molecule on a gold surface.
• DFT results served as a benchmark to assess the accuracy of various force fields.
• Molecular dynamics (MD) simulations were conducted using different force fields to study water structure and dynamics.

Main Results:

• Lennard-Jones potentials failed to accurately reproduce the DFT-derived water-gold configurational energy landscape.
• Morse and Buckingham potentials provided a more accurate representation of the water-gold interaction energy.
• MD simulations using different force fields yielded significantly different structural and dynamic properties of water on gold.

Conclusions:

• The choice of force field significantly impacts the simulated structure and dynamics of water at gold surfaces.
• There is a critical need for experimental data to validate and refine force fields for water-gold interactions.
• Further development and validation of realistic force fields are essential for accurate modeling of these systems.