Spin-polarized DFT calculations are performed utilizing the Vienna ab initio simulation package (VASP 6.3.1) code. Exchange-correlation interaction in Kohnshame equation was described by Perdew-Burke-Ernzerhof (PBE) with the framework of the generalized-gradient approximation (GGA). Projector augmented wave (PAW) potential, featuring the computational efficiency of the ultrasoft pseudopotential and the accuracy of plane wave method, was adopted in this treatment of ion-electron interaction. Because of self-interaction error of pure DFT method, which is failed to describe the strong-correlated electrons, the GGA + U strategy was utilized to correct the result of exchange interaction energy. The U value of 3.65 eV for Cr and 5.64 eV for Ni were evaluated by the linear response method (see Figure ). In all calculations, the energy cutoff of 500 eV was used to expand the plane wave basis set.