[Imrantarin]

Hi All

I am reading on this topic and arrived at the following equation

X(g)  + e  x⁺ + 2e

Am I correct in assuming that we lose electron to form positive ion because due to high energy electrons from electron gun, there is repulsion between electron and one electron gets knocked out to form positive ion.

I hope my question making sense.

[Enthalpy]

Hi, from what I read, an electron gun is only one possible way to make the ions in a TOF spectrometer, possibly not the most usual one.

The process you describe properly does exist, and is the most efficient one in a gas discharge too, which is one other possible ion source in a TOF spectrometer.

An electron arriving with a low energy might be absorbed by the molecule. And an ion can also knock an electron from a molecule, but is far less efficient than an electron for that, because the mass discrepancy makes the energy transfer less efficient than between electrons.