First-principles prediction of structural and electronic properties of RTAsO (R=La, Gd and T=Co, Ni) compounds by LSDA+U calculations

RTAsO (R=rare-earth and T=transition metals) compounds have been studied using density functional theory with the local spin-density approximation (LSDA). In order to take into account the strong on-site Coulomb interaction U present in RTAsO, we have also performed the LSDA+U calculations. We investigated the electronic structure with on-site Coulomb potential for the R-derived 4f and T-derived 3d orbitals to obtain the correct ground state of RTAsO. The structural parameters, band structures and density of states have been given in detail. Overall, the technique developed and tested in this work holds promise in enabling accurate and fully predictive calculations of strongly correlated electron materials. A detailed analysis shows that the LSDA+U method provides the better description of our systems. We note that there is no ab-initio study related to these materials.