The correlation of the auger parameter with refractive index: An XPS study of silicates using Zr Lα radiation

This is the authors' abstract. We don't add key points for this paper.

The value of using Zr Lα x‐rays as a source for the XPS study of AlSi compounds is proved by their ability to generate strong Al and Si is and KLL Auger peaks and with sufficient resolution for peak energies to be determined accurately. A study of the resultant Al and Si Auger parameters has been made for some 30 silicates and comparison with refractive index data allows the Auger parameters to be scaled directly with the polarization energy of the surrounding O ions. The O polarizability dominates the bulk polarizability in silicates and its magnitude is controlled by its site co‐ordination number and the electronegativity of charge‐balancing cations in the structure. Oxygen ions surrounding Si and tetrahedral Al sites have highly variable, but strongly interdependent, polarizabilities; however, the O polarizability is almost invariant around octahedral Al sites. The correlation of relaxation energy in a silicate lattice with polarizability is finally compared with the London force interaction between molecules.