Electron capture ionization is the ionization of a gas phase atom or molecule by attachment of an electron to create an ion of the form . The reaction is
![{\displaystyle {\ce {A + e^- ->[M]A^-}}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/f68ddaa7eab7c0763171ab895b1429bc6b398a61)
where the M over the arrow denotes that to conserve energy and momentum a third body is required (the molecularity of the reaction is three).
Electron capture can be used in conjunction with chemical ionization.[1]
- ^ Donald F. Hunt; Frank W. Crow (1978), "Electron capture negative ion chemical ionization mass spectrometry", Analytical Chemistry, 50 (13): 1781, doi:10.1021/ac50035a017