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The effect of simultaneous substitution of a fluctuating cation and a divalent cation in LaMnO 3 perovskite modifies the properties of the material to exhibit large valence colossal magnetoresistance (CMR) effect. A good example of these properties is (La 1−2x Pr x Ca x )MnO 3 (LPCMO) type CMR material. In this communication it is reported that, with the increase in x (for x = 0.1, 0.15, 0.2), the T c varies between 100 and 120 K with improvisation in metal-insulator transition. Interestingly, resistance increases with x from few hundred ohms to few kilo ohms with corresponding decrease in the unit cell volume. The results of the studies using X-ray diffraction (XRD), electrical resistivity, magnetoresistance and ac susceptibility measurements on LPCMO samples for understanding the structural, transport and magnetic properties are discussed in detail.

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