High quality sodium perchlorate has been analyzed as one in a series of chlorine-oxy anion sodium salts, Chloride to Perchlorate. The spectra include survey and high resolution scans over the major photopeaks, the sodium Auger transitions and the valence band of the compound. Several references have been listed as additional sources of information of the nature of these materials and previous XPS analyses [see R. Manne, J. Chem. Phys. 46, 4645 (1967); R. G. Copperthwaite, J. Chem. Soc. Dalton Trans. 1977, 1117; R. Prins and T. Navakov, Chem. Phys. Lett. 9, 593 (1971); R. Prins, J. Chem. Phys. 61, 2580 (1974); and F. Solymosi, Structure and Stability of Salts of Halogen Oxyacids in the Solid Phase (Wiley-Interscience, New York, 1977)]. © 1994 American Vacuum Society.