ion–molecule reaction

physics

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June 29, 2026

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Ion-molecule reactions are processes where electrically charged atoms or molecules (ions) interact with neutral molecules. These reactions are crucial for understanding the chemistry of various environments, including flames, electrical discharges, the upper atmosphere, and materials exposed to radiation.1

In physics, an ion pair is formed when a neutral atom or molecule gains enough energy to split into a positive and a negative ion. This ionization can occur through various means, such as when energetic particles or radiation interact with matter. In chemistry, ion pairs can also refer to oppositely charged ions temporarily held together by electrostatic attraction in concentrated solutions. Mass spectrometers are key instruments for investigating these ion-molecule reactions.231

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radiation
Purely physical effects
…in what is called an ion–molecule reaction. In either case new chemical species are created. These transformed ions and radicals, as well as the electrons, parent ions, and excited states, are capable of reacting with themselves and with molecules of the medium, as well as with a solute (a dissolved…
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…in what is called an ion–molecule reaction. In either case new chemical species are created. These transformed ions and radicals, as well as the electrons, parent ions, and excited states, are capable of reacting with themselves and with molecules of the medium, as well as with a solute (a dissolved…
Read More