Ion Sources

Electron Ionization or Electron Impact (EI)

Atmospheric Pressure Chemical Ionization (APCI)

Atmospheric Pressure Photoionization (APPI)

Electrospray Ionization (ESI)

 

 

Electron Ionization

In electron ionization or electron impact ion source ions are produced due to wave transfer of energy from accelerated electrons to analyzed molecules which subsequently ionize and fall apart.

In electron ionization source electrons are emmited from the heated fillament and move towards anode. Typical kinetic energy of the electrons is 70eV. Since typical energy of ionization for most of organic molecules is 5-10eV, the energy of electrons is enough to ionize molecules and break several chemical bonds causing extensive fragmentation.

Atmospheric Pressure Chemical Ionization (APCI)

Atmospheric Pressure Photoionization (APPI)

Electrospray Ionization (ESI)