The formation of an ion when an atom or molecule in a disctete state with an energy greater than the ionization threshold loses an electron spontaneously without further interaction with an energy source. Synonymous with pre-ionization.
|Considered between 2004 and 2006 but not included in the 2006 PAC submission|
|This is an unofficial draft definition presented for information and comment.|
Orange Book Entry
This occurs when an internally supra-excited atom or molecular moiety (in the preionization state) loses an electron spontaneously without further interaction with an energy source.