Systematic XPS studies of metal oxides, hydroxides and peroxides

The results of a systematic XPS study, under high controlled conditions, of different basic oxides of transition metals, alkali and alkaline-earth met als are presented; the XPS data of some hydroxides and peroxides are also r eported. Variations of the O 1s binding energies are analysed and one point of interest is the large binding energy scale obtained for O 1s peaks all associated with a "2-" formal charge. Through extended Huckel theory-tight binding (EHT-TB) calculations, attempts are made to rationalize the observe d variations. The results illustrate the significant differences between re al charges on oxygen atoms in transition metal and alkaline-earth oxides.