Calculation of polarization using a density functional method with localized charge
1Center for Computational Materials Science, Naval Research Laboratory, Washington, D.C. 20375-5345, USA.
Physical Review Letters
|October 4, 2000
Summary
A new density functional method simplifies interpreting material polarization. This approach uses localized charge densities, offering a simpler alternative to conventional band-structure calculations for properties like polarization.
Area of Science:
- Condensed matter physics
- Materials science
- Computational chemistry
Background:
- Accurate calculation of material properties is crucial for scientific advancement.
- Conventional band-structure methods provide high accuracy but can be complex.
- Interpreting properties like polarization requires robust theoretical frameworks.
Purpose of the Study:
- To introduce a novel density functional method for calculating material properties.
- To provide a simpler interpretation of polarization and related phenomena.
- To demonstrate the applicability of the method to various ionic and semiconductor materials.
Main Methods:
- A density functional approach is employed.
- The total charge density is represented as a sum of self-consistently determined localized densities.
- The method's accuracy is compared against conventional band-structure techniques.
Main Results:
- The described method offers a more straightforward interpretation of polarization compared to traditional approaches.
- While generally less accurate than band-structure methods, it provides valuable insights.
- Successful application of the method to NaCl, MgO, and AlP demonstrates its utility.
Conclusions:
- The localized density functional approach provides a computationally accessible route to understanding polarization.
- This method serves as a valuable tool for materials science research, complementing existing techniques.
- Further investigations can explore its application to a wider range of materials and properties.
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