Question

Describe the mechanism of the production of an LMM Auger electron.

Short answer

The sample is first evaporated before being ionized in gas phase sources. In desorption sources, a solid or liquid sample is instantaneously converted into gaseous ions.

Step-by-step solution

MNN Auger Electron 

The mechanism of the production of an MNN Auger electron is based on a two step processes. In the first step, the analyte is exposed to a beam of electrons or X-rays which results in the formation of an electronically excited ion as $A^{+*}$.

$\mathrm{A}+{\mathrm{e}}_{\mathrm{i}}^{-}⟶{\mathrm{A}}^{+*}+{\mathrm{e}}_{\mathrm{i}}^{\text{'}-}+{\mathrm{e}}_{\mathrm{A}}^{-}$

Where, ${\mathrm{e}}_{\mathrm{i}}^{-}$represents an incident electron from the source, ${\mathrm{e}}_{\mathrm{i}}^{\text{'}-}$represents the same electron after its interaction with $A$and hence has lost some of its energy, and $e_A^{-}$represents an electron which is ejected from one of the orbitals of$A.$

Advantage of Gaseous and Desorption sources 

The relaxation of the excited ion $A^{+*}$is followed by the ejection of an Auger electron role="math" localid="1645545316500" ${e^{-}}_A$with kinetic energy $E_K$in the second step.

An M electron is removed at the start of the MNN Auger transition. A transition of a $N$electron to the M orbital occurs next, followed by the ejection of a second N electron.