Electronic structure study of NaCo2O4 by LAPW method

The electronic structure of NaCo2O4 is calculated by linearized augmented plane wave (LAPW) method. Virtual crystal approximation and supercell calculations are used to investigate it. The theoretical values of electric field gradient (EFG) are calculated. We find that the theoretical EFG with GGA approximation are consistent with the experimental results. The electronic structures of other ACo2O4 (A=Na, K, Rb, Cs) compounds are also calculated to study the peculiar properties of NaCo2O4.