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Electron ionization. Electron ionization (EI, formerly known as electron impact ionization [1] and electron bombardment ionization [2]) is an ionization method in which energetic electrons interact with solid or gas phase atoms or molecules to produce ions. [3] EI was one of the first ionization techniques developed for mass spectrometry. [4]
Ion Gun, used to direct a beam of ions at a target sample. An electron ionization ion source is typically used to ionize noble gas atoms such as He, Ne or Ar, while heating of wafers containing alkali atoms is used to create an alkali ion beam. The ions thus created hold a positive charge, typically +1, due to the ejection of electrons from the ...
The electron binding energy derives from the electromagnetic interaction of the electron with the nucleus and the other electrons of the atom, molecule or solid and is mediated by photons. Among the chemical elements, the range of ionization energies is from 3.8939 eV for the outermost electron in an atom of caesium to 11.567617 keV for the ...
Electron capture ionization (ECI) is the ionization of a gas phase atom or molecule by attachment of an electron to create an ion of the form A −•.The reaction is + 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).
Adiabatic ionization is a form of ionization in which an electron is removed from or added to an atom or molecule in its lowest energy state to form an ion in its lowest energy state. [ 16 ] The Townsend discharge is a good example of the creation of positive ions and free electrons due to ion impact.
A certain amount of energy, which may be large enough, is required to remove an electron from an atom or a molecule in its ground state. [12] [13] In chemi-ionization processes, the energy consumed by the ionization must be stored in atoms or molecules in a form of potencial energy or can be obtained from an accompanying exothermic chemical change (for example, from a formation of a new ...
The hot cathode can be a metal filament, a coated metal filament, or a separate structure of metal or carbides or borides of transition metals. Vacuum emission from metals tends to become significant only for temperatures over 1,000 K (730 °C; 1,340 °F). Charge flow increases dramatically with temperature.
Resonance electron capture [3] is also known as nondissociative EC. The compound captures an electron to form a radical anion. [4] The energy of the electrons are about 0 eV. The electrons can be created in the Electron Ionization source with moderating gas such as H 2, CH 4, i-C 4 H 10, NH 3, N 2, and Ar. [5] After the ion captures the electron, the complex formed can stabilize during ...