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Long-range corrected hybrid meta-generalized-gradient approximations with dispersion corrections.
You-Sheng Lin1, Chen-Wei Tsai, Guan-De Li
1Department of Physics, National Taiwan University, Taipei 10617, Taiwan.
The Journal of Chemical Physics
|April 24, 2012
Summary
We developed ωM05-D, a new long-range corrected hybrid meta-generalized gradient approximation (GGA) functional. This accurate computational chemistry tool excels in predicting thermochemistry, kinetics, and molecular interactions, aiding density functional approximation assessments.
Area of Science:
- Computational Chemistry
- Quantum Chemistry
- Materials Science
Background:
- Density functional approximations (DFAs) are crucial for predicting molecular properties.
- Existing functionals often struggle with long-range interactions and diverse chemical applications.
- Accurate assessment of DFAs requires reliable benchmark databases.
Purpose of the Study:
- To introduce a novel long-range corrected hybrid meta-generalized gradient approximation (GGA) functional, ωM05-D.
- To evaluate the performance of ωM05-D across a broad spectrum of chemical applications.
- To present new benchmark databases for assessing DFA accuracy.
Main Methods:
- Development of a long-range corrected hybrid meta-GGA functional (ωM05-D) by incorporating empirical dispersion corrections into the M05 functional.
- Testing the functional's accuracy for thermochemistry, kinetics, noncovalent interactions, geometries, and electronic properties.
- Creation of three new databases: IP131 (ionization potentials), EA115 (electron affinities), and FG115 (fundamental gaps).
Main Results:
- The ωM05-D functional demonstrates high accuracy for a wide range of chemical properties.
- The new databases provide reliable experimental data for evaluating DFA performance.
- ωM05-D shows significant improvements over previous functionals in various benchmarks.
Conclusions:
- The ωM05-D functional offers a robust and accurate tool for diverse chemical predictions.
- The developed databases are valuable resources for advancing the field of density functional theory.
- This work contributes to the development of more reliable computational chemistry methods.
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