Meta Functionals*

Supplementing density functional Hamiltonians with Hubbard-U on-site interaction terms is the computationally most efficient approach to remedy self-interaction errors present in standard density functional theory (DFT) calculations of the electronic structure of e.g. transitional metal oxides. Reactants and products typically require different values of the interaction strength U, rendering total energy differences meaningless. While an empirical correction scheme has been developed for bulk transition metal oxide sites [Jain et al., Phys. Rev. B 84, 045115 (2011)] based on experimental reference enthalpies, the presence of a surface or bulk defects requiring adjusted values of U again limits the predictive power of DFT+U for reaction energies.
Here, an extended DFT+U method is presented, scaling the strength of on-site interactions with kinetic energy terms. The method allows for calculation of total energy corrections directly from the computed electronic structure, which can be used to estimate reaction energies from a combination of DFT+U and standard semi-local DFT calculations.