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Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics
Published on: April 12, 2019
Modelling charge transfer reactions with the frozen density embedding formalism
Michele Pavanello1, Johannes Neugebauer
1Gorlaeus Laboratories, Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands. m.pavanello@chem.leidenuniv.nl
The Journal of Chemical Physics
|December 24, 2011
Summary
Frozen density embedding (FDE) accurately calculates electronic couplings for DNA hole transfer reactions. Results depend on the chosen density-functional theory exchange-correlation functional, with exact exchange performing best.
Area of Science:
- Quantum chemistry
- Computational biology
- Biophysics
Background:
- Density-functional theory (DFT) is a powerful computational method.
- Frozen density embedding (FDE) is a DFT subsystem approach for modeling complex systems.
- Understanding charge transfer in DNA is crucial for biological processes.
Purpose of the Study:
- To assess the accuracy of FDE for calculating electronic couplings in DNA hole transfer.
- To investigate the impact of different exchange-correlation functionals on FDE calculations.
- To evaluate FDE for modeling diabatic states in nucleobase dimers.
Main Methods:
- Utilized the FDE subsystem formulation of DFT.
- Generated charge-localized, diabatic states for hole transfer reactions.
- Calculated electronic couplings for 5'-GG-3' and 5'-GT-3' B-DNA dimers.
- Employed the two-state model and assumed small differential overlap.
Main Results:
- FDE electronic couplings showed good agreement with benchmark values when using functionals with high exact exchange.
- Semilocal generalized gradient approximation (GGA) functionals significantly overestimated electronic couplings.
- The choice of exchange-correlation functional critically impacts the accuracy of FDE for hole transfer.
Conclusions:
- FDE is a viable method for studying DNA charge transfer reactions, provided appropriate functionals are used.
- Functionals with substantial exact exchange are recommended for accurate electronic coupling calculations with FDE.
- Further research may explore mitigating overestimation issues with semilocal functionals.
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