Electrons do not reflect photons; instead, they absorb them, transitioning to a higher energy state before re-emitting a photon. This process occurs within the context of an atom, where an electron in an orbital absorbs a photon, not the electron alone. The discussion clarifies that neither electrons nor atoms reflect light; rather, surfaces composed of numerous molecules reflect light due to their smoothness on the scale of visible wavelengths. The distinction between a "beam of light" and a "photon" is emphasized, highlighting that photons do not possess a physical size.
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This is an important point that applies for potential energy in general. We sometimes speak as though it is localized to one part of a system, but generally such comments are misleading.Mister T said:The potential energy is a property of the atom, not a property of anyone single component of the atom.
Yes, I sat down and did what you recommended so many times. I even explained (cited from Wikipedia) how the momentum is transferred to the rest of the atom ...Dale said:... Did you ever sit down and work out the conservation of momentum and energy as I recommended?
If so, then you should have seen that scattering can conserve both energy and momentum with just the electron, but absorption cannot. That is why a single electron can scatter a photon but cannot absorb it. It is all about conservation principles. The same conservation principles lead to both behaviors.
Any charged particle can participate in elastic scattering. So as long as the atom is ionized it can participate. Inelastic scattering can involve even an unionized atom.DanMP said:the whole atom can?
Whether or not the electron is bound or free. If the electron is free then the electron scatters, if the electron is bound then the atom scatters. A bound electron cannot be treated independently of the rest of the atom.DanMP said:If yes, what decides if the atom as a whole or one of its electrons would scatter an incident photon?
So, in scattering it is always about the electron ... We say that the atom scatters, just because the electron is part of an atom. This is very close to how I interpreted the absorption: the electron "receives" the photon but, because it is a part of an atom and momentum & energy are transferred to the rest of the atom, we say that the atom scatters/absorbs ...Dale said:... Whether or not the electron is bound or free. If the electron is free then the electron scatters, if the electron is bound then the atom scatters. A bound electron cannot be treated independently of the rest of the atom. ...
No, it is not always about the electron. It is only about the electron if the electron is unbound. I was pretty clear about that.DanMP said:So, in scattering it is always about the electron .
As far as I can tell the word “receives” has no meaning in this context.DanMP said:the electron "receives" the photon
Ok, thanks for your replies.Dale said:No, it is not always about the electron ...