Dense Bi(Fe 1/2 Cr 1/2 )O 3 ceramics with R 3c crystal structure were synthesized by solidstate reaction under high pressure. Transmission electron microscope observations revealed an incommensurable superstructure along 110 direction. Magnetization measurements indicated a transition to a cooperative magnetic state below ∼ 130 K. Dielectric properties of Bi(Fe 1/2 Cr 1/2 )O 3 showed a dielectric constant anomaly located at ∼ 140 K indicating the giant dielectric relaxation in multiferroic

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... 1/2 Cr 1/2 )O 3 compound, which can be explained by the enhanced conductivity and possible Maxwell-Wagner contribution. Large dielectric frequency dispersion was observed at 140-185 K, and was supposed to be a thermal activated intrinsic process.