X-Ray Photoelectron Spectra of Aluminum Oxides: Structural Effects on the “Chemical Shift”

The aluminum (2p) electron spectra of several anhydrous and “hydrous” aluminum oxides have been recorded, and the binding energies have been measured. A simple electrostatic model is employed to explain the observed shift in binding energy and relate it to differences in structure and hydrogen bonding. Two conclusions can be drawn: structural differences must be considered when interpreting photoelectron spectra for inorganic crystalline substances; and hydrogen bonding with anions may have a measurable effect on the binding energy of core electrons of the cations.