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Appearance energy

Appearance energy is the minimum energy that must be supplied to a gas phase atom or molecule in order to produce an ion. In mass spectrometry, it is accounted as the voltage to correspond for electron ionization. This is the minimum electron energy that produces an ion. In photoionization, it is the minimum photon energy of a photon that produces some ion signal. For example, the indene bromide ion (IndBr+) only loses bromine at an incident photon energy of 10.2 eV, so the product, indenyl, has an appearance energy of 10.2 eV.

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Appearance energy (also known as appearance potential) is the minimum energy that must be supplied to a gas phase atom or molecule in order to produce an ion. In mass spectrometry, it is accounted as the voltage to correspond for electron ionization. 1 This is the minimum electron energy that produces an ion.2 In photoionization, it is the minimum photon energy of a photon that produces some ion signal. For example, the indene bromide ion (IndBr+) only loses bromine at an incident photon energy of 10.2 eV, so the product, indenyl, has an appearance energy of 10.2 eV.3

See also

See also

References

References

  1. IUPAC, Compendium of Chemical Terminology, 5th ed. (the "Gold Book") (2025). Online version: (2006–) "Appearance energy". doi:10.1351/goldbook.A00421
  2. Kerwin, Larkin; Marmet, Paul (1960), "Recent Appearance Potential Measurements Using an Electrostatic Electron Selector", Journal of Applied Physics, 31 (12): 2071, Bibcode:1960JAP....31.2071K, doi:10.1063/1.1735504
  3. Hemberger, Patrick; Steinbauer, Michael; Schneider, Michael; Fischer, Ingo; Johnson, Melanie; Bodi, Andras; Gerber, Thomas (2010-04-15). "Photoionization of Three Isomers of the C 9 H 7 Radical". The Journal of Physical Chemistry A. 114 (14): 4698–4703. doi:10.1021/jp9068569. ISSN 1089-5639.