The candidate multiferroic BiCrO 3 and its chemical neighbors BiMnO 3 and BiFeO 3 are known to be ferromagnetic and ferroelectric respectively. With structural distortions driven by the strongly polarizable Bi ions, we present results of the first-principles density functional calculations using the (FP-LMTO) method with the spin-orbit coupling for those materials in the pseudo-cubic perovskite phase. The results showed that the valence bands in these compounds are formed by the 6p orbitals of bismuth and 3d orbital's of the transition metals. Our results indicate that these materials have metallic behavior for spin-up polarization but being a clear tandance for semiconductor spin-down BiMnO 3 .

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