Synchrotron infrared measurements were conducted over the range 100 to 8000 cm -1 on a self-doped La x MnO 3-δ (x~0.8) film. From these measurements we determined the conductivity, the effective number of free carriers, and the specific phonon modes as a function of frequency. While the metal-insulator transition temperature (T MI ) and the magnetic ordering temperature (T C ) approximately coincide, the free carrier density onset occurs at a significantly lower temperature (~45 K below). This suggests that local distortions exist below T MI and T C which trap the e g conduction electrons. These regions with local distortions constitute an insulating phase which persists for temperatures significantly below T MI and T C .The initial large drop in resistivity is due to the enhanced magnetic ordering while further drops correspond to reductions in the insulating phase which increase the number of free carriers. : 78.20.-e, 72.80.-r, 75.47.Lx, 64.75.St
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