Static dielectric permittivity of ice from first principles
Nicéphore Bonnet1, Nicola Marzari2
1Department of Materials Science and Engineering, MIT, Cambridge, Massachusetts 02139, USA.
Physical Review Letters
|December 27, 2014
Summary
This study computes the static permittivity of ice from first principles, revealing how electric fields affect its dielectric properties. Findings highlight the impact of approximations on dielectric calculations and compare favorably with experimental data.
Area of Science:
- Computational Physics
- Materials Science
- Quantum Chemistry
Background:
- Understanding the dielectric properties of ice is crucial for various scientific disciplines.
- Previous calculations often relied on approximations that could affect accuracy.
Purpose of the Study:
- To compute the static permittivity of ice from first principles.
- To investigate the influence of electric fields on ice's dielectric behavior.
- To determine the generalized Kirkwood factor and molecular dipole moment.
Main Methods:
- Utilized a novel method combining slab approach and Berry phase calculations to determine the molecular dipole.
- Employed Monte Carlo simulations with first-principles model Hamiltonians for polarization fluctuation sampling.
- Calculated static permittivity and generalized Kirkwood factor as a function of electric field.
Main Results:
- Accurately determined the molecular dipole moment in ice.
- Demonstrated that common exchange-correlation functional approximations overestimate permittivity and enhance ferroelectric configurations.
- Observed that dielectric saturation effects align well with experimental results.
Conclusions:
- The first-principles computation provides a robust method for calculating ice's static permittivity.
- Approximation effects in functionals are significant and need careful consideration.
- The study validates the computational approach by comparing dielectric saturation with experimental data.
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