Electron changing energy state

[Johnahh]

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.

 

[ZapperZ]

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.

 

[Popper]

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,

 

[Johnahh]

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.

 

[sardar]

In quantum mechanics, the behavior of particles, such as electrons, is described by wave functions and probabilities rather than classical trajectories. Therefore, the concept of work function, which is based on classical mechanics, does not apply in this scenario.

When an electron absorbs a photon and moves to a higher energy state, it does not require any external work or energy transfer. This is because the energy of the photon is directly transferred to the electron, causing it to jump to a higher energy level.

Moreover, in quantum mechanics, the concept of energy levels is discrete, meaning that the electron can only occupy certain energy states and cannot exist in between them. So, when the electron drops back down to a lower energy state, it releases a photon with the same energy as the one it absorbed, as this is the only possible energy state for the electron to occupy.

In the photoelectric effect, the work function refers to the minimum energy required to remove an electron from a metal surface. This is a different concept than the energy levels of an electron within an atom, and it does not apply in the scenario of an electron moving to a higher energy state within an atom.

In conclusion, the behavior of electrons in atoms is best described using quantum mechanics, and classical concepts such as work function do not apply in this context. The movement of electrons between energy states is a fundamental aspect of quantum mechanics and does not require any external work or energy transfer.