The temperature dependence of the resistivity (ρ) and magneto-resistance (MR) effect of La1−xLixMnOy (x=0.05, 0.1, 0.15, 0.2 & 0.25 at.%) fixed valence doped compounds were studied between 80 and 320 K. X-ray powder diffraction (XRD) at room temperature shows that the samples are single phase. The resistivity of all samples with and without magnetic field shows a metal–semiconductor (M–S) transition ... إقراء المزيد