Will an electron release energy when it is added into an atom?

[Sameer Tahir]

According to my understanding, when an electron is added into an atom, it emits energy in the form of photons because it is a form of de-excitation or relaxation. This is when electron affinity will be positive (exothermic). But there is one case where energy must be provided to an electron for it to overcome the repulsive forces of the electrons of the atom in which it is going to be added. Now, in this case I think the electron will still release its energy in the form of photons when it is added. However, because net energy change (Energy released in the form of photons - Energy provided to the electron) is negative (endothermic) therefore in this case we say the electron affinity of such atoms is negative.

Is this understanding of Electron Affinity correct?

 

[Nugatory]

But there is one case where energy must be provided to an electron for it to overcome the repulsive forces of the electrons of the atom in which it is going to be added.

Is it even possible to add an electron if the process is not net exothermic?

 

[Sameer Tahir]

We can accelerate the electron using thermal energy or electric potential to provide that electron sufficient kinetic energy to "penetrate" its way into the repulsion of that atom's electrons.

 

[weirdoguy]

Ok, but will it create a bounded system?

 

[Sameer Tahir]

I think Electron will release the energy in the form of EM radiations. But I am not sure.

 

[Nugatory]

I think Electron will release the energy in the form of EM radiations. But I am not sure.

Yes, the released energy will appear in the form of EM radiation. But I think you're missing the point of @weirdoguy's (probably rhetorical) and my (definitely rhetorical) questions.

 

[Sameer Tahir]

Sorry but I am not a physics guy. I am just at college level. If you can simplify your point so I can understand it.