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Accurate Surface Chemistry beyond the Generalized Gradient Approximation: Illustrations for Graphene Adatoms
Benjamin G Janesko1, Veronica Barone2, Edward N Brothers3
1Department of Chemistry, Texas Christian University , Fort Worth, Texas 76129, United States.
Journal of Chemical Theory and Computation
|November 20, 2015
Summary
Generalized gradient approximations (GGAs) underestimate surface reaction barriers, similar to gas-phase chemistry. Meta-GGAs and screened hybrids offer improved accuracy for surface simulations and are computationally feasible.
Area of Science:
- Computational chemistry
- Surface science
- Materials science
Background:
- Density functional theory (DFT) simulations are crucial for surface chemistry.
- Generalized gradient approximations (GGAs) are commonly used but have known limitations.
Purpose of the Study:
- To evaluate the performance of GGAs, meta-GGAs, and screened hybrids for surface chemistry simulations.
- To assess the computational feasibility of advanced functionals for surface science.
Main Methods:
- Simulations of oxygen (O) and lithium (Li) adatoms on graphene surfaces.
- Comparison of results obtained using GGAs, meta-GGAs, and screened hybrid functionals.
Main Results:
- GGAs exhibit limitations in simulating surface chemistry, including underestimated reaction barriers.
- Meta-GGAs and screened hybrids provide systematically improved accuracy for surface systems.
- These advanced functionals are computationally feasible for surface chemistry applications.
Conclusions:
- GGAs are inadequate for accurate surface chemistry simulations.
- Meta-GGAs and screened hybrids represent a more accurate and feasible approach for surface science.
- Continued exploration of advanced functionals is recommended for surface chemistry research.
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