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Electron binding energies

	Label	Orbital	eV [literature reference]
	K	1s	4038.5 [2]
	L I	2s	438.4 [3]
	L II	2p1/2	349.7 [3]
	L III	2p3/2	346.2 [3]
	M I	3s	44.3 [3]
	M II	3p1/2	25.4 [3]
	M III	3p3/2	25.4 [3]

Notes

All values of electron binding energies are given in eV. The binding energies are quoted relative to the vacuum level for rare gases and H₂, N₂, O₂, F₂, and Cl₂ molecules; relative to the Fermi level for metals; and relative to the top of the valence band for semiconductors.

I am grateful to Gwyn Williams (Jefferson Laboratory, Virginia, USA) who provided the electron binding energy data. The data are adapted from references 1-3. They are tabulated elsewhere on the WWW (reference 4) and in paper form (reference 5).

References

1. J. A. Bearden and A. F. Burr, "Reevaluation of X-Ray Atomic Energy Levels," Rev. Mod. Phys., 1967, 39, 125.
2. M. Cardona and L. Ley, Eds., Photoemission in Solids I: General Principles (Springer-Verlag, Berlin) with additional corrections, 1978.
3. J. C. Fuggle and N. Mårtensson, "Core-Level Binding Energies in Metals," J. Electron Spectrosc. Relat. Phenom., 1980, 21, 275.
4. Gwyn Williams WWW table of values
5. D.R. Lide, (Ed.) in Chemical Rubber Company handbook of chemistry and physics, CRC Press, Boca Raton, Florida, USA, 81st edition, 2000.

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