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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.
Gas phase ion chemistry is a field of science encompassed within both chemistry and physics. It is the science that studies ions and molecules in the gas phase, most often enabled by some form of mass spectrometry. By far the most important applications for this science is in studying the thermodynamics and kinetics of reactions.
The other gas, called a quenching gas, has to have a lower ionization energy than the first excited state of the noble gas. The energy of the excited, but neutral, noble gas atoms then can ionize the quench gas particles by energy transfer via collisions; known as the Penning effect.
Chemi-ionization is the formation of an ion through the reaction of a gas phase atom or molecule with another atom or molecule when the collision energy is below the energy required to ionize the reagents. [1] [2] The reaction may involve a reagent in an excited state [3] or may result in the formation of a new chemical bond.
The DART ion source is a kind of gas-phase ionization, and it requires some sort of volatility of the analyte to support thermally assisted desorption of analyte ions. [14] This limits the size range of the molecules that can be analyzed by DART i.e. m/z 50 to 1200. [1] [15] DART-MS is capable of semi-quantitative and quantitative analysis. To ...
A cylindrical version of a Penning trap, with open endcaps to permit axial access. B indicates the magnetic field, and E indicates the electric field used for storage of the particles in the trap centre. A Penning trap is a device for the storage of charged particles using a homogeneous magnetic field and a quadrupole electric field.
Chemical ionization in an atmospheric pressure electric discharge is called atmospheric pressure chemical ionization (APCI), which usually uses water as the reagent gas. An APCI source is composed of a liquid chromatography outlet, nebulizing the eluent, a heated vaporizer tube, a corona discharge needle and a pinhole entrance to 10 −3 torr ...
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. The resultant swirling ions are accelerated to strike a chemically active cathode (usually titanium ...