Transferable Gaussian Attractive Potentials for Organic/Oxide Interfaces

Area of Science:

• Surface chemistry
• Computational materials science
• Physical chemistry

Background:

• Organic/oxide interfaces are crucial for lubrication and corrosion.
• Molecular dynamics (MD) simulations offer experimental insights.
• Current force fields inadequately represent Lewis acid/base interactions at these interfaces.

Purpose of the Study:

• To develop an improved force field for simulating organic molecule interactions with oxide surfaces.
• To incorporate stabilizing Lewis acid/base interactions into MD simulations.
• To enhance the accuracy of simulations for lubrication and corrosion phenomena.

Main Methods:

• Introduction of an attractive Gaussian potential to standard Lennard-Jones and electrostatic models, creating the Gaussian Lennard-Jones (GLJ) potential.
• Simulation of interactions between oxygenated/amine molecules and hematite/γ-alumina surfaces.
• Validation of the GLJ potential by comparing simulation results with experimental data and first-principles calculations.

Main Results:

• The GLJ potential shows improved accuracy with low root mean square deviation (RMSD) for various molecules on hematite and γ-alumina surfaces.
• Simulations using GLJ reveal strong structuration and reduced mobility of organic films on oxide surfaces.
• GLJ simulations provide more realistic dynamics compared to standard Lennard-Jones potentials, aligning with theoretical adsorption energies.

Conclusions:

• The GLJ potential offers a significant advancement in accurately simulating organic/oxide interfaces.
• This improved modeling capability is vital for understanding and designing materials for lubrication and corrosion resistance.
• The GLJ potential provides a more physically realistic representation of surface interactions, crucial for various chemical applications.