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Analysis of the Heyd-Scuseria-Ernzerhof density functional parameter space
Jonathan E Moussa1, Peter A Schultz, James R Chelikowsky
1Sandia National Laboratories, Albuquerque, New Mexico 87185, USA. godotalgorithm@gmail.com
The Journal of Chemical Physics
|June 7, 2012
Summary
The Heyd-Scuseria-Ernzerhof (HSE) screened exchange density functionals offer improved accuracy for semiconductor band gaps. This study optimizes HSE parameters, balancing accuracy and computational cost for better density functional development.
Area of Science:
- Computational chemistry
- Materials science
- Quantum mechanics
Background:
- Heyd-Scuseria-Ernzerhof (HSE) functionals enhance standard semilocal functionals like Perdew-Burke-Ernzerhof (PBE).
- HSE functionals reduce computational cost by limiting Fock exchange to short inter-electron distances.
- These functionals depend on Fock exchange fraction and screening length parameters.
Purpose of the Study:
- Systematically investigate the two-parameter space of HSE functionals.
- Assess the performance of hybrid screened exchange (sX) functionals.
- Identify optimal parameters balancing accuracy and computational efficiency.
Main Methods:
- Exploration of the parameter space defined by Fock exchange fraction and screening length.
- Evaluation of functional performance across various tests.
- Comparison with existing parameterizations like HSE06.
Main Results:
- Identified three useful parameterizations: sX-PBE, HSE12, and HSE12s.
- HSE12 minimizes overall error across tested metrics.
- HSE12s matches HSE06 accuracy while halving the screening length, reducing computational cost.
- Analysis revealed error trends guiding future functional development.
Conclusions:
- Optimized HSE parameters provide a balance between accuracy and computational efficiency.
- The HSE12s functional offers a promising route for reduced computational expense.
- Systematic parameter space analysis is crucial for advancing density functional theory.
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