Electron capture ionization

Electron capture ionization is the ionization of a gas phase <a href="/facts/Atom/FoQ4kGN5">atom</a> or <a href="/facts/Molecule/N9ljSfFq">molecule</a> by attachment of an <a href="/facts/Electron/L0KBo5cW">electron</a> to create an ion of the form 
 
 
 
 
 
 A
 
 −
 
 
 
 
 
 {\displaystyle {\ce {A^-}}}
 
. The reaction is

A
          +
          
            e
            
              −
            
          
          
            
              →
              
                M
              
            
          
          
            A
            
              −
            
          
        
      
    
    {\displaystyle {\ce {A + e^- ->[M]A^-}}}

where the M over the arrow denotes that to conserve <a href="/facts/Energy/wd8PrQM7">energy</a> and <a href="/facts/Momentum/TTkGv5eY">momentum</a> a third body is required (the <a href="/facts/Molecularity/KSUIR0Kp">molecularity</a> of the reaction is three).
Electron capture can be used in conjunction with <a href="/facts/Chemical_ionization/m0hVaA3p">chemical ionization</a>.

Electron capture ionization open-in-new

Electron capture ionization