Density functional calculation of effective Coulomb interaction in La1−xCaxMnO3

The electronic structures of perovskite oxides La2/3Sr1/3MnO3 are studied with density functional methods. Our calculations indicated that the strong electron correlation, which has evident influence on the split of Mn 3d-orbitals and the forming of double exchange, is very important to get the correct densities of states (DOS) of La2/3Sr1/3MnO3. In addition, results show that 4.1 eV is a good choice for the on-site Coulomb parameter U.