is it related to fermi energy? what is the exact equation form?
What electron? Do you mean electrons in metals? Electrons in vacuum, in atoms, in accelerators, etc.
You questions is way too vague.
sorry. I miss the word. It is electrons in metals at room temperature. Thank you very much.
The electrons in a metal have a distribution of energies. Not just a single value.
The Fermi energy is a good estimate of the order of magnitude of the energy of the electrons.
At zero K the highest energy is the Fermi energy.
At room temperature some electrons will have energies slightly higher than Fermi energy.
Try starting with 1/40 eV, and see what you get.
This will be an estimate of how "high" they will go over the Fermi level at room temperature.
Typical values of Fermi energies are of a few eV.
Thank you very much. But how to derive the fermi energy of electrons in metal? (to obtain the number of a few eV) Is the only way to do this by density of states equation and the number n in metal? Is there any other equation?
Can you describe in more detail what are you after?
From the OP it was not clear what you know about it. If you know the equations, what is your problem? You don't like them? You want more a more complex treatment than in introductory solid state books? You want to know how can one measure the Fermi energy?
It's not fair to expect people to try to guess what is your question about.
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