Transport properties in Gd doped La2/3Ca1/3MnO3

The electronic transport in the paramagnetic range of mixed valence manganites is studied here through resistivity and thermopower of Gd3+ doped La2/3Ca1/3MnO3. The analysis of the experimental results of the high temperature limiting value for the thermopower reveals a discrepancy with theory, which could be interpreted as a consequence of an increasing entropy term with lattice distortion. The polaron binding energy is found to be independent of the lattice distortion. © 2002 Elsevier Science B.V. All rights reserved.