Electronic transport properties of compounds with temperature unstable intermediate valence of Ce

The results of thermoelectric power (Sf) and electrical resistivity (ρf) measurements connected with the temperature unstable valence of Ce are presented for the compounds CeNi, CeNi2 and CeNi2Si2 in the temperature range of 4-800 K. It is shown that Sf(T) and ρf(T) are well described in the narrow peak model for the density of the Lorentzian shape f states situated near the Fermi level. The width and position of the peak depend on the temperature and are defined by the characteristic Kondo temperature.