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Volume optimization was performed to obtain the theoretical lattice constants by using the generalized gradient approximation(GGA).The electronic and magnetic properties of Heusler alloys Co_2CrZ(Z = Ga,Ge, As) were investigated by using local spin density approximation(LSDA).Amongst the systems under investigation, Co_2CrGe and Co_2CrGa give 100%spin polarization at the Fermi level(E_f)- Co_2CrGe and Co_2CrGa are the most stable half-metallic ferromagnets(HMFs);their E_F lie exactly at the gap of 0.24 eV and 0.38 eV,respectively,in the spin-down channel.Even though Co_2CrAs gives a distinct and bigger gap as compared to Co_2CrGa and Co_2CrGe, its E_F is not located at the middle of the gap in the spin-down channel.We have also found that the total magnetic moments increase as the Z goes from Ga to As.The calculated density of states and band structures show the HMF character for Co_2CrGe and Co_2CrGa.
Volume optimization was performed to obtain the theoretical lattice constants by using the generalized gradient approximation (GGA). The electronic and magnetic properties of Heusler alloys Co_2CrZ (Z = Ga, Ge, As) were investigated by using local spin density approximation (LSDA). Amongst the systems under investigation, Co_2CrGe and Co_2CrGa give 100% spin polarization at the Fermi level (E_f) -Co_2CrGe and Co_2CrGa are the most stable half-metallic ferromagnets (HMFs); their E_F lie exactly at the gap of 0.24 eV and 0.38 eV , respectively, in the spin-down channel. Even though Co_2CrAs gives a distinct and bigger gap as compared to Co_2CrGa and Co_2CrGe, its E_F is not located at the middle of the gap in the spin-down channel. We have also found that the total magnetic moments increase as the Z goes from Ga to As. The calculated density of states and band structures show the HMF character for Co_2CrGe and Co_2CrGa.