First principles investigation on the band gap of the ground state of LaCoO3

The band gap of LaCoO3 in ground state is obtained from the generalized gradient approximation (GGA) with on-site Coulomb correction (GGA + U) calculations (U = 3.4 eV,J = 0.49 eV), which agrees with the experimental result very well. A series of local spin density approximation (LSDA) with on-site Coulomb corrections (LSDA+U) and GGA+U calculations are performed with various U and J parameters to understand the recently published band gaps of 1.43 eV from LSDA + U (U = 8.33 eV) and 1.0 eV from GGA + U (U = 2.7) calculations. The partial density of states (PDOSs) are presented to investigate the origin of the band gap. (c) 2010 Elsevier Ltd. All rights reserved.