A periodic charge-dipole electrostatic model: parametrization for silver slabs
I V Bodrenko1, M Sierka, E Fabiano
1National Nanotechnology Laboratory (NNL), Istituto Nanoscienze-CNR, Via per Arnesano 16, 73100 Lecce, Italy.
The Journal of Chemical Physics
|October 9, 2012
Summary
We developed a new periodic charge-dipole electrostatic model (PCDEM) for describing periodic systems. This model accurately predicts polarizability and induced charge density in silver slabs using a novel density measure.
Area of Science:
- Computational Chemistry
- Materials Science
- Condensed Matter Physics
Background:
- Accurate electrostatic modeling of periodic systems is crucial for understanding their properties.
- Existing models may struggle with describing the linear response and charge distribution in periodic structures.
Purpose of the Study:
- To introduce an extended charge-dipole model for periodic systems.
- To apply this model to calculate the polarizability of silver slabs.
- To develop a method for obtaining a unique and accurate parametrization.
Main Methods:
- Development of the periodic charge-dipole electrostatic model (PCDEM).
- Utilizing charge- and dipole-type Gaussian basis functions for linear response description.
- Employing the continuous fast multipole method for long-range electrostatic interactions.
- Introduction of the integral squared density measure for unique parametrization.
Main Results:
- The PCDEM accurately describes the polarizability of silver slabs when both charges and dipoles are considered.
- A unique parametrization was achieved using the integral squared density measure.
- This parametrization accurately describes both polarizability and induced charge density profile.
Conclusions:
- The PCDEM provides an accurate and efficient method for electrostatic modeling of periodic systems.
- The integral squared density measure is essential for obtaining physically meaningful results.
- The study highlights the importance of considering both charge and dipole contributions and the limitations of electrostatic approximations.
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