Abstract
Earlier observations on the magnitudes of chemical shifts of photoelectron and core-type Auger lines, and the concept of the role of polarizability, have been combined to produce a unified concept of the role of polarization in determining line position. With core-type Auger lines, polarization effects are more important in determining chemical shifts than are changes in electron density on the atom in the ground state. A parameter, termed the Auger parameter, is proposed as a specific property of a chemical and physical state. It is accurately determinable to ±0.1 eV, and with most elements to which it is applicable the range among compounds is several eV. Differences in the Auger parameter are attributable solely to changes in the polarizability of the solid compounds.