Physicochemical Effects on X-Ray Spectra

To a first approximation, inner-shell electron properties have atomic character. In fact, the environment of an atom influences its levels, as mentioned in Chapter 2.1.2.1, pp. 202, 208. 

The chemical and physical state of an X-ray emitting or absorbing atom may modify the energy, width, and relative intensity of diagram and nondiagram transitions connected to creation or annihilation of inner holes in the electronic shells. 

Some sources of general information of historical and fundamental interest are [1 to 4]. 

In absorption spectra, under the same conditions as for emission lines, changes of structure and shifts are observed for the main edges, white lines, XANES and EXAFS. They are widely exploited. Refer to [1 to 5, 9 to 20] and especially to several proceedings of EXAFS conferences (cited on p. 240). 

Shifts of K and L absorption edges on going from metal to metal compound  

---