B The Mystery of Excited Electrons: Are They Moving Away from the Nucleus?

Mustafa Bayram
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when an electron is excited to the conduction band is it move further from the nucleus?
Are free electrons in the conduction band further from valence electrons?
I saw this picture that seems problematic to me. what do you think?

conduction band.png
 
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I am not sure what that picture represents, but (1) it looks like a very classical-minded picture and (2) the band structure is a feature in energy, not in space.

Generally speaking, higher-energy electrons are farther away from the nucleus, and therefore further away from core electrons. But the proper description is quantum mechanical, so you can't assign a precise position to an electron. Even high-energy electrons have a non-zero probability of being found near the nucleus.

In the conduction band, electrons are no longer tethered to a particular atom and are free to move over long distances.
 
DrClaude said:
I am not sure what that picture represents
Me neither, but for some reason I remember that I need to pick up some thing at Target.
DrClaude said:
In the conduction band, electrons are no longer tethered to a particular atom
This is key. Can you write it again?

If all the electrons were strongly localized to a nucleus, you wouldn't have conduction!
 
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