Abstract
The energy of a large number of oxidation reactions of transition metal oxides is computed using the generalized gradient approach (GGA) and methods. Two substantial contributions to the error in GGA oxidation energies are identified. The first contribution originates from the overbinding of GGA in the molecule and only occurs when the oxidant is . The second error occurs in all oxidation reactions and is related to the correlation error in orbitals in GGA. Strong self-interaction in GGA systematically penalizes a reduced state (with more electrons) over an oxidized state, resulting in an overestimation of oxidation energies. The constant error in the oxidation energy from the binding error can be corrected by fitting the formation enthalpy of simple nontransition metal oxides. Removal of the binding error makes it possible to address the correlation effects in transition metal oxides with the method. Calculated oxidation energies agree well with experimental data for reasonable and consistent values of U.
- Received 23 November 2005
DOI:https://doi.org/10.1103/PhysRevB.73.195107
©2006 American Physical Society