Name: Martin
Status: student
Age: N/A
Location: N/A
Country: Australia
Date: N/A
Question:
Can a single electron in an excited state return
to its ground state in several jumps back to the ground state
emitting several photons of different energy? If so, is it
common ? Any good online references ?
Replies:
Yes indeed, a single electron (or X-ray photon) can excite bound
electrons to higher energy unoccupied orbitals, or even ionize the
atom. Then what happens is the target atom finds itself with an
unoccupied "hole" in the electron structure. Electrons of higher
energies then cascade by multiple pathways until the excited
electron is one in the outermost shell (valence electron). This
effect is known as the Auger effect ("Auger" is pronounced
somewhere between "Oh -Zshay" and "O. J."). As you might expect the
photons produced by the cascading effect to "fill" the lower energy
hole can get quite complicated. Only fairly recently have advances
in instrumental technology allowed routine use of Auger
spectroscopy as an analytical tool. A "Google" search on "Auger
spectroscopy" or "Auger effect" will give you many references. One
that is fairly concise and complete is:
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