Screened hybrid functionals applied to ceria: Effect of Fock exchange

Authors: Dou Du, Matthew J. Wolf, Kersti Hermansson, and Peter Broqvist

We investigate how the redox properties of ceria are affected by the fraction of Fock exchange in screened HSE06-based hybrid density functionals, and we compare with PBE+U results, and with experiments when available. We find that using 15% Fock exchange yields a good compromise with respect to structure, electronic structure, and calculated reduction energies, and represents a significant improvement over the PBE+U results. We also investigate the possibility to use a computationally cheaper HSE06//PBE+U protocol consisting of structure optimization with PBE+U, a subsequent lattice parameter rescaling step, and, finally, a single-point full hybrid calculation. We find that such a composite computational protocol works very well and yields results in close agreement with those where HSE06 was used also for the structure optimization.

Phys. Rev. B, Volume 97, Page 235203.
https://doi.org/10.1103/PhysRevB.97.235203

 

 

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