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Since the energy levels of atoms are quantized, I was wondering what happens if an electron is hit by a photon whose energy is higher than electron's first excited state but lower than second excited state. Does it excite to the first excited state? If yes, what happens to the remaining energy?

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marked as duplicate by Qmechanic Feb 13 '13 at 1:09

This question was marked as an exact duplicate of an existing question.

1 – Mew Feb 13 '13 at 0:36
up vote 0 down vote accepted

Let the electron ground state have energy $E_g$, let the first excited state have energy $E_1$, and let the second excited state have energy $E_2$.

Let the energy of the photon be given by $E_p = hf$.

Now it isn't the energy of the exited states that is important in transitions, but the energy differences between states.

So instead I'll assume you mean the following condition: $(E_1 - E_g) < hf < (E_2 - E_g)$.

Now as the atom absorbs $hf$, it causes the electron to transition to the first excited state. There is therefore excess energy of $hf - (E_1 - E_g)$. This excess energy is either converted to kinetic energy in the atom, or is reflected as a new photon with lower frequency and energy $E' = hf'$.

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Any reference for this @Chris? I don't doubt, just want to have dipper idea. – Samir Chauhan Feb 13 '13 at 3:59
Unless I'm missing something this isn't correct. If the photon energy doesn't match an allowed transition energy it won't be absorbed and won't excite any transition. In solids it's possible to get the behaviour you describe (e.g. Raman scattering) because the lattice can participate. However this won't happen for an isolated atom. – John Rennie Feb 13 '13 at 10:02

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