Permittivity of an Inhomogeneous Dipolar Lattice Fluid
Bachelor Thesis - Max Planck Institute for Intelligent Systems
Project Overview
Developed and validated a computational model of confined dipolar fluids to investigate how dielectric properties change near charged surfaces. The project combined Monte Carlo simulations with density functional theory (mean-field and modified mean-field approaches) to study local and global permittivity, dipole orientation, and polarization effects. Results successfully reproduced the experimentally observed reduction in permittivity near walls and highlighted the influence of system size and intermolecular interactions on dielectric behavior. A key contribution was the comparison of simulation and analytical methods, revealing limitations and thermodynamic inconsistencies in common mean-field approximations while demonstrating that a simplified lattice model can capture the essential physics of confined polar fluids.
Methodology
Monte-Carlo Simulation
Implemented in C++ to model the statistical mechanics of dipolar particles in lattice structures. The simulations provided insights into the collective behavior of particles under various confinement conditions.
Density Functional Theory
Applied theoretical framework (mean-field and modified mean-field approaches) to analyze the density distributions and thermodynamic properties of the fluid systems, complementing the simulation results with analytical predictions.
Key Contributions
- Computational Model Development: Developed and validated a computational model of confined dipolar fluids to investigate dielectric property changes near charged surfaces.
- Theoretical & Simulation Integration: Combined Monte Carlo simulations with density functional theory (mean-field and modified mean-field approaches) to study local and global permittivity, dipole orientation, and polarization effects.
- Experimental Validation: Results successfully reproduced the experimentally observed reduction in permittivity near walls.
- System Analysis: Highlighted the influence of system size and intermolecular interactions on dielectric behavior.
- Method Comparison: Key contribution was the comparison of simulation and analytical methods, revealing limitations and thermodynamic inconsistencies in common mean-field approximations.
- Model Simplification: Demonstrated that a simplified lattice model can capture the essential physics of confined polar fluids.
Technical Stack
Key Findings
Permittivity Reduction
Successfully reproduced experimentally observed reduction in permittivity near charged walls
System Size Effects
Identified influence of system size on dielectric behavior in confined fluids
Intermolecular Interactions
Demonstrated impact of intermolecular interactions on dielectric properties
Method Comparison
Revealed limitations and thermodynamic inconsistencies in mean-field approximations