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In this paper, we study the structural and electrical properties of the perovskite manganite La 0.7 Ba 0.2 Ca 0.1 Mn 1−x Cr x O 3 , synthesized by the solid-state reaction method. The Rietveld refinement of X-ray diffraction data indicates that there is no structural change owing to Cr substitution in La 0.7 Ba 0.The conductivity of all samples was measured as a function of frequency in the range between 40 and 10 6 Hz and a temperature ranging from 160 to 300 K. The ac conductance spectrum is found to obey the Jonscher universal power law: G ac = G dc +Aω n . The variation of the conductivity exponent (n) with temperature confirms the presence of hopping in the conduction process. According to dc conductance study, electronic conduction is found to be dominated by thermally activated hopping. The Cr content affects the activation energy (E a ). Its values decrease from E a = 72 meV for x = 0 to E a = 34 meV for x = 0.15.

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