Electron changing energy state

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When a photon is absorbed by an electron, it transitions from a ground state to a higher energy level, such as n=3, and can later emit a photon of the same energy. This process differs from the photoelectric effect, which involves the liberation of electrons from metals rather than isolated atoms. The energy required for this transition can be viewed as analogous to a work function, as it represents the energy needed to promote the electron to a higher state. Additionally, the energy from the photon contributes to changes in both the potential and kinetic energy of the electron, as described by quantum mechanics. Understanding these distinctions is crucial for accurately interpreting electron behavior in atomic systems.
Johnahh
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When a photon is absorbed by an electron the electron moves from ground state to a higher energy let's say n=3. this electron can then drop back down and emit a photon of the exact energy as the photon that was absorbed.
My question is why is there no work function or energy transfer as it where, when the electron moves up from ground to n=3? what made me think about this was the photo electric effect. the Kmax of an electron is hf-∅. I think i may be trying to think about it using classical physics instead of quantum.
 
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Johnahh said:
When a photon is absorbed by an electron the electron moves from ground state to a higher energy let's say n=3. this electron can then drop back down and emit a photon of the exact energy as the photon that was absorbed.
My question is why is there no work function or energy transfer as it where, when the electron moves up from ground to n=3? what made me think about this was the photo electric effect. the Kmax of an electron is hf-∅. I think i may be trying to think about it using classical physics instead of quantum.

This is not really the photoelectric effect, because there is no "electric" part, i.e. no liberation of electron. The electron is still in a bound state.

Secondly, the typical photoelectric effect is done on metals, not isolated atoms.

Thirdly, the energy level, in some way, IS the "work function" in a loose sense, because this is the energy needed to promote the electron from ground state to your n=3 level. Without that energy, such a transition can't occur.

BTW, you can't simply equate the KE of the electron as being such a difference. The photon energy went into the change in the electrons potential and kinetic energy, as dictated by the solution of the Schrodinger equation for that particular state.

Zz.
 
Johnahh said:
When a photon is absorbed by an electron the electron moves from ground state to a higher energy let's say n=3.
A nit pick for clarificaton: An electron cannot absorb a photon (at least not a real one). Think of it as the atom that is absorbing the energy,
 
Secondly, the typical photoelectric effect is done on metals, not isolated atoms.

So when thinking about the photoelectric effect we have to consider the properties of the material rather than a single atom that makes sense.

BTW, you can't simply equate the KE of the electron as being such a difference. The photon energy went into the change in the electrons potential and kinetic energy, as dictated by the solution of the Schrodinger equation for that particular state.

I am not advanced enough for the Shrodinger equation I'm afraid. but I get what your saying I think. lol

Thanks for the clarification Popper I was unaware of this.
 
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