SEEBECK COEFFICIENTS OF FE3-YTIYO4 AND FE3-XZNXO4 SINGLE-CRYSTALS ANDTHEIR INTERPRETATION

Seebeck coefficient data have been measured for Fe3-yTiyO4 and for Fe3 -xZnxO4 single crystals in the range 75-300 K and for 0 less-than-or-e qual-to y less-than-or-equal-to 0.9 and 0 less-than-or-equal-to x less -than-or-equal-to 0.29. The data have been rationalized in terms of a small polaron model, on the basis of an adaptation of the standard ord er-disorder theory. Very good agreement is obtained between the two-pa rameter theory and experiment. In this model the Ti sites do not parti cipate in electronic conduction.