X-ray absorption and Mössbauer study of the CeSb-CeTe system

CeSb is a cubic trivalent Ce compound. Its very abnormal magnetic diagram contains 16 different phases depending on magnetic field and temperature. These complex physical properties could be interpreted in the framework of the p-f mixing model based on a strong mixing interaction between 4f electrons and p-band holes. The substitution of Sb by the less electronegative element Te, filling the p-valence band, modifies the hole concentration and yields very important effects. Thus, the study of the Ce(Te)Sb system is a good tool to check the validity of the model. In this paper we present a study of the CeSb 1 − x Te x solid solution by X-ray absorption experiments at the Ce and Sb L 111 edge and by Mössbauer spectroscopy ( 121Sb, 125Te). From these results, the evolution of the nature of the chemical bonding under substitution is discussed, in correlation with the x-dependence of the electronic and magnetic properties.