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Penning ionization is a form of chemi-ionization, an ionization process involving reactions between neutral atoms or molecules. [1] [2] The Penning effect is put to practical use in applications such as gas-discharge neon lamps and fluorescent lamps, where the lamp is filled with a Penning mixture to improve the electrical characteristics of the lamps.
Penning ionization is a form of chemi-ionization, an ionization process involving reactions between neutral atoms or molecules. [7] The Penning effect, as it is often called, describes an ionization chain reaction caused by high energy collision between excited inert gas (i.g. argon) metastable atoms and trace gas impurities whose ionization ...
Penning ionization refers to the interaction between a gas-phase excited-state atom or molecule G * and a target molecule M resulting in the formation of a radical molecular cation M +., an electron e −, and a neutral gas molecule G: [7]
[1] [4] Chemi-ionization can proceed through the Penning, associative, dissociative or rearrangement ionization reactions. Includes reactions that produce a free electron or a pair of ions (positive and negative). [5] [6] This process is helpful in mass spectrometry because it creates unique bands that can be used to identify molecules. [7]
Penning ionization is a form of chemi-ionization involving reactions between neutral atoms or molecules. [ 14 ] [ 15 ] The process is named after the Dutch physicist Frans Michel Penning who first reported it in 1927. [ 16 ]
The Penning mixture used in plasma displays is usually helium or neon with small percentage of xenon, at several hundred torr. Penning mixtures with the formulas of argon–xenon, neon–argon, argon–acetylene, and xenon–TMA are used as filler gases in gaseous ionization detectors. Other kinds of Penning mixture include helium–xenon.
The DART ionization process can produce positive or negative ions depending on the potential applied to the exit electrode. This ionization can occur for species desorbed directly from surfaces such as bank notes, tablets, bodily fluids (blood, saliva and urine), polymers, glass, plant leaves, fruits & vegetables, clothing, and living organisms.
The basic element of the common ion pump is a Penning trap. [6] A swirling cloud of electrons produced by an electric discharge is temporarily stored in the anode region of a Penning trap. These electrons ionize incoming gas atoms and molecules.