Abstract: XPS inner shell. satellite peaks and its valence band spectra of the pyridoxygen complexes of rare earth decahydrodecaborate nave been investigated. The binding energies of the ligand atoms show variation with increasing atomic number of rare earth elements and a specific "tetrad effect" is observed in the plot of binding energies of ligand atoms versus rare earth atomic numbers. The XPS valence band spectra of different rare earth complexes are characteristic for the rare earth elements.

Key words: XPS, Rare earth complexes, Decahydrodecaborate