A high resolution X-ray photoemission, XPS, study of PbMg1/3Nb2/3O3 is reported. The binding energy of the Pb core lines are consistent with a formal valence of 2+, while a valence of 5+ is found for Nb. In addition, on the basis of present data, the existence of different coordination sites for Pb, Nb and Mg is discarded. Finally, within the limit of the present experimental conditions, domains with non-homogeneous electrostatic charges, as proposed by some structural models, are not observed. Instead, the XPS results are consistent with a random distribution of Nb and Mg ions on the cationic site.
