Electronic properties of gases

Depending on its nature, a gas element interacting with a solid can act as an electron acceptor or donor. If its orbitals are full, then the gas is necessarily an electron donor, and this property will be characterized by the energy the system needs to extract an electron from the molecules or atoms of gas. 

This energy is the ionization potential, denoted by h. The same gas element can successively free many electrons, and each extraction will be characterized respectively by its ionization potential h, h, I3, etc. 

If the orbitals of the gas molecule or the gas atom are empty, then they will be able to accept electrons, and the corresponding energy then identifies with an electron affinity Ai. 

In such a case, there are multiple possible energy corrligurations. Oxygen is the perfect example, with 02,0, o . 

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