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of both the downward and upward electrons involved m the Auger process.

The spectra oi a Dumber of aowe-wbat heavier elements appear in the lower row. These line.- are due to LM transitions and also tend to correlate with X-ray energies, but some lines are beginning to appear which tlie selection rules for photon emission forbid. The selection rule- must be relaxed for the ra-diationless Auger proie-- Λ- the atomic number increases, the spec­tra become more complex and over­lapping occurs, for example, be­tween the copper and nickel spectra. The growing complexity in the spectra, winch reflect- the growing complexity of the atomic subsbell -tincture, is shown in Figure» 6-8. These spectra are for germanium, molybdenum, and tungsten with iron and carbon impuritii

Information on location of Auger peaks i- summarised in Figure 9. Virtually all the elements have readily identifiable features be­tween ">() and 1000 eV because the various possible transitions tend to overlap in this range. Although Auger analysis ι- most effective and easiest! for the light elements, it can al-o b< used for heavy clémente. Ill this ca-e . because of the ext ra lilies not t a b u l a t e d m X - r a y d a t a . empirical determinations mu-t be made from previously recorded

800 1000 1200 1400

Electron Energy, ev

Figure 6. Auger spectrum for germanium Ph

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