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Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Comparison of the performance of exact-exchange-based density functional methods
Fenglai Liu1, Emil Proynov, Jian-Guo Yu
1College of Chemistry, Beijing Normal University, Beijing 100875, People's Republic of China.
The Journal of Chemical Physics
|September 25, 2012
Summary
New density functional theory (DFT) methods, including Becke'05 (B05) and Perdew-Staroverov-Tao-Scuseria (PSTS), show promise for describing nondynamic electron correlation. These functionals accurately model challenging systems, outperforming others in specific cases.
Area of Science:
- Computational Chemistry
- Quantum Chemistry
- Materials Science
Background:
- Describing nondynamic electron correlation remains a significant challenge for Density Functional Theory (DFT).
- Existing models like Becke'05 (B05) and Perdew-Staroverov-Tao-Scuseria (PSTS) utilize exact-exchange density, posing computational challenges.
- Efficient self-consistent implementations are crucial for applying these advanced functionals.
Purpose of the Study:
- To report a self-consistent resolution-identity (RI) implementation of the PSTS functional, removing previous basis set limitations.
- To implement and evaluate the Mori-Sanchez-Cohen-Yang-2 (MCY2) functional, which includes full exact exchange.
- To assess the performance of PSTS, B05, and MCY2, alongside other established DFT functionals, for systems with nondynamic correlation.
Main Methods:
- Self-consistent RI implementation of the PSTS functional.
- Implementation of the MCY2 functional.
- Validation of PSTS, B05, and MCY2 on thermochemistry, reaction barriers, and dissociation energy curves, including comparisons with B3LYP, M06-HF, M06-2X, ωB97X, and TPSSh.
Main Results:
- PSTS, B05, and MCY2 generally perform well, with B05 and MCY2 showing slightly better average performance than PSTS.
- M06-2X and ωB97X excel in standard thermodynamic properties, while B05, MCY2, and PSTS are superior for hydrogen abstraction and dissociation processes.
- B05 uniquely provides qualitatively correct dissociation curves for symmetric radicals (e.g., He(2)(+)), and PSTS, B05, and MCY2 correctly describe the strongly correlated NO dimer.
Conclusions:
- The implemented PSTS, B05, and MCY2 functionals demonstrate significant promise for accurately modeling nondynamic electron correlation in DFT.
- These advanced functionals offer improved descriptions for challenging chemical phenomena like dissociation processes and strongly correlated systems.
- Further development and application of these functionals are warranted to overcome limitations of current DFT methods.
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