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Fully nonlocal kinetic energy density functionals: a proposal and a general assessment for atomic systems
David García-Aldea1, J E Alvarellos
1Departamento de Fisica Fundamental, UNED, Apartado 60, 141, E-28080 Madrid, Spain. dgaldea@fisfun.uned.es
The Journal of Chemical Physics
|December 3, 2008
Summary
New nonlocal kinetic energy density functionals accurately describe atomic systems. These functionals show excellent local behavior and total energies, offering efficient computation via momentum space integrals.
Area of Science:
- Quantum Chemistry
- Computational Physics
- Materials Science
Background:
- Developing accurate kinetic energy density functionals is crucial for electronic structure calculations.
- Existing functionals often struggle with localized systems and accurately describing kinetic energy density behavior.
Purpose of the Study:
- To present and evaluate a family of fully nonlocal kinetic energy density functionals.
- To assess their performance in describing atomic systems, focusing on total kinetic energy and local kinetic energy density.
Main Methods:
- Construction of nonlocal functionals incorporating von Weizsacker and logarithmic density dependence.
- Application and testing of these functionals on atomic systems.
- Analysis of both total kinetic energy and the local behavior of kinetic energy density.
Main Results:
- The proposed fully nonlocal functionals provide a good description of the local kinetic energy density.
- These functionals maintain accurate results for the total kinetic energies of atomic systems.
- Most functionals allow for evaluation via a single momentum space integral, enabling quasilinear computational scaling.
Conclusions:
- The developed nonlocal kinetic energy density functionals show significant promise for accurate and efficient electronic structure calculations.
- Their ability to capture the local behavior of kinetic energy density is a key strength.
- The computational efficiency achieved through momentum space integration makes them suitable for larger systems.
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