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Electron excitation + photon emission and the colours we see

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ovin8k:
When an electron absorbs a photon and is excited (not sure if thats the right phrase) so it enters a higher energy level; then when its relaxed returning back to ground level, is the colour we see corresponding to the wavelength caused by the photons energy = the energy it took for the electron to go from one energy level to the other.

Hence why some objects are one colour and other objects other colours, as theyre made from different atoms so the distance between energy levels is different requiring different energies to be absorbed? If yes what's a better way of explaining it, and if not what affects the wavelength caused by the photon energy emitted?

I'm not really sure how to phrase it, so i'm hoping someone will be able to get at what I mean.

Corribus:
Most of the colors you see are not caused by the kind of photon emission you are describing (what you might term fluorescence). Rather most colors you see are due to absorption and scatter events. A good example is a leaf. Sun light is (approximately) white, meaning in the visible range (about 400-700 nm), there are roughly equivalent* amounts of photons spanning wavelengths from 400 nm (blue, say) all the way to 700 nm (red). Leaves have a lot of chlorophyll, which is a molecular pigment that  pretty strongly absorbs photons ranging from 350-450 nm and from about 600-700 nm. So when white light falls on a leaf, most of the photons in those ranges are absorbed (where their energy contributes to photosynthesis) and the rest of them - from 450 nm to 600 nm - are scattered and reflected. Guess what color most photons in that range look like to your eye? Yeah, green. So, the color of MOST objects is due to what wavelengths are left over and scattered to your eye after molecules in the surface of the object absorb a selrct fraction of the white ambient light around you.

Keep in mind, though, that the perception of color depends not only on what energy photons reach your eye (which depends on how many of each wavelength started from the various light sources around and the number of photons that are absorbed/scattered by various surfaces) but also on how efficient your eye is as picking up the photons that make it through your lenses.

*let us pretend, anyway

Borek:
+1 to what Corribus wrote, although your thinking is not completely wrong - yes, color of the emitted light is a function of the energy level difference between orbitals occupied by the electron when excited/relaxed. What I would change in your post though is that these orbitals are not function of just "atoms" - when you deal with a molecule electrons occupy molecular orbitals. On some level they are conceptually not different from atomic orbitals, they are just characteristic for the molecule composed of many atoms.

ovin8k:

--- Quote from: Corribus on May 03, 2022, 11:47:02 PM ---Most of the colors you see are not caused by the kind of photon emission you are describing (what you might term fluorescence). Rather most colors you see are due to absorption and scatter events.

--- End quote ---

Are there any articles that I could read that you'd recommend?

Also when you burn metals, the flame appears as different colours. This is due to different wavelengths of light (from what I gathered). What causes the different wavelengths to be emitted during combustion for the different metals? What causes the different wavelengths so that aluminium is silver white, and boron is bright green?

ovin8k:

--- Quote from: Borek on May 04, 2022, 02:53:02 AM ---What I would change in your post though is that these orbitals are not function of just "atoms" - when you deal with a molecule electrons occupy molecular orbitals. On some level they are conceptually not different from atomic orbitals, they are just characteristic for the molecule composed of many atoms.

--- End quote ---

What's another way of thinking about this, I don't understand what you mean by orbitals not being functions of just "atoms". What do you mean by a function an an atom?

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