Ionization

The generation of one or more ions. It may occur, e.g. by loss of an electron from a neutral molecular entity, by the unimolecular heterolysis of such an entity into two or more ions, or by a heterolytic substitution reaction involving neutral molecules, such as:

http://www.nicmila.org/Gold/Output/SVG/I03183-1.png

http://www.nicmila.org/Gold/Output/SVG/I03183-2.png

http://www.nicmila.org/Gold/Output/SVG/I03183-3.png

The loss of an electron from a singly, doubly, etc. charged cation is called second, third, etc. ionization. This terminology is used especially in mass spectroscopy.