Emission/Absorption and electron orbits

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    Electron Orbits
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Discussion Overview

The discussion revolves around the concepts of emission and absorption in relation to electron orbits, particularly focusing on the potential effects of relativistic Doppler shifting on spectral lines. Participants explore the implications of electron velocities, atomic transitions, and the nature of light interactions with atoms, touching on both theoretical and experimental aspects.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants propose that if electrons orbit the nucleus, relativistic Doppler shifting should be observable, potentially leading to broader spectral lines for certain elements like gold.
  • Others argue that the Doppler effect is more relevant in specific contexts, such as light reflecting off surfaces, and question the applicability of this effect to atomic transitions.
  • One participant mentions Compton scattering as a related phenomenon but distinguishes it from the relativistic Doppler effect being discussed.
  • There is a contention regarding whether electrons emit radiation while in orbit or only during transitions between orbitals, with some asserting that emission occurs only during transitions.
  • Several participants express uncertainty about the relationship between the properties of individual atoms and the observed color of solids, suggesting that bulk properties may not directly reflect atomic behavior.
  • Discussions also touch on relativistic corrections to energy levels in higher orbitals and their potential impact on spectral lines.
  • Some participants challenge each other's interpretations and reasoning, leading to a mix of clarifications and disagreements about the underlying physics.

Areas of Agreement / Disagreement

Participants do not reach consensus on the implications of relativistic effects on spectral lines or the nature of electron emission. Multiple competing views remain regarding the interaction of light with electrons and the relevance of atomic versus solid-state physics.

Contextual Notes

Limitations include unresolved assumptions about the nature of electron orbits, the definitions of emission versus transition, and the applicability of relativistic effects in different contexts. The discussion also reflects a mix of classical and quantum mechanical perspectives, which may lead to confusion.

fourdoughnut
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Just a thought; if indeed electrons transit around the nucleus, shouldn't we see relativistic doppler shifting as their orbits will have them either receding away or moving towards us?
Thus, shouldn't elemental spectral lines really exist as 'spectral bars' of measurable bandwidth using high resolution detectors?

Finally, with some atoms this affect should be blatantly obvious - i.e Gold atoms possesses electrons that move @ around half the speed of light + ... therefore some of its Ab'/Emission lines should be particularly broad.

What do you think?
 
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Yes, I believe the doppler shift is apparent when light reflects off shiny metallic surfaces. It makes mirrors look silvery. Unfortunately, I can't find any confirmation of this, so it could be inaccurate.
 
fourdoughnut said:
Just a thought; if indeed electrons transit around the nucleus, shouldn't we see relativistic doppler shifting as their orbits will have them either receding away or moving towards us?
It has another name: Compton Scattering. It's apparent only for high frequency em radiation, that is at least X-rays. In the more "common" interaction with atoms, instead, light doesn't interact with electrons as if they were "particle-like", but with the "wavelike" electronic cloud (or the "electronic gas" in a metal), so the mechanism is different, don't know how much Doppler effect (due to "moving electrons") there could be.
There is a Doppler effect when light interacts with single atoms of a gas, due to the atoms' velocities (and this does indeed broaden the atomic spectrum lines).
 
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lightarrow said:
It has another name: Compton Scattering. It's apparent only for high frequency em radiation, that is at least X-rays. In the more "common" interaction with atoms, instead, light doesn't interact with electrons as if they were "particle-like", but with the "wavelike" electronic cloud (or the "electronic gas" in a metal), so the mechanism is different, don't know how much Doppler effect (due to "moving electrons") there could be.
There is a Doppler effect when light interacts with single atoms of a gas, due to the atoms' velocities (and this does indeed broaden the atomic spectrum lines).

I disagree, the Compton Effect is based on conservation of energy in a 'recoil' type scenario and has nothing to do with the relativistic doppler mechanism I've postulated, however thanks for your input.


Cheers.
 
fourdoughnut said:
Just a thought; if indeed electrons transit around the nucleus, shouldn't we see relativistic doppler shifting as their orbits will have them either receding away or moving towards us?
...

This sounds classical. The electron doesn't emit while orbiting, but rather when it changes orbitals. How does this affect your idea?
 
Well it has be proved that relativistic electron velocities account for certain observable properties i.e the colour of Gold, therefore these quantum jumps do not raise any issues here.

Cheers.
 
fourdoughnut said:
I disagree, the Compton Effect is based on conservation of energy in a 'recoil' type scenario and has nothing to do with the relativistic doppler mechanism I've postulated, however thanks for your input.
Cheers.
If you didn't mean to refer to light interacting with the electrons, then, of which (possible) Doppler effect are you talking about?
 
fourdoughnut said:
Well it has be proved that relativistic electron velocities account for certain observable properties i.e the colour of Gold, therefore these quantum jumps do not raise any issues here.

Cheers.

I don't know about gold, but the color of a solid typically has very little to do with the property of the individual atoms that make up the solid. If not, then diamond would look very much like graphite. But they don't!

Electrons in its atomic orbital emits no EM radiation. That's a given fact. Only when it makes a transition will there be an emission of a photon. There are relativistic corrections to various energy levels as one goes up to higher orbital states, such as d and f orbitals. This certainly would affect the nature of the energy spectra that one would obtain. However, I don't think this is what you're asking for.

If you start confusing how "atoms" behave with what you notice from the bulk solid, then you'll get into trouble very quickly. Solid state physics is not identical to atomic/molecular physics. That's why they are two separate areas of study.

Zz.
 
lightarrow said:
If you didn't mean to refer to light interacting with the electrons, then, of which (possible) Doppler effect are you talking about?

I though I'd explained this ... as electrons orbit the nucleus, photon emission will occur when they're either moving towards a detector or away (following so far) therefore, the wavelength of those moving towards a detector will shorten and lengthen correspondingly for those moving away, though my gedanken affect would only be obvious when said electrons are moving @ relativistic velocities, thus producing very short wavelengths i.e x-rays. This leads me to think the Compton Effect to be a mis-understood phenomenon and one which can more sensibly be explained with relativistic doppler shifting.

Nobel prize on stand-by :smile:
 
  • #10
ZapperZ said:
I don't know about gold, but the color of a solid typically has very little to do with the property of the individual atoms that make up the solid. If not, then diamond would look very much like graphite. But they don't!

Electrons in its atomic orbital emits no EM radiation. That's a given fact. Only when it makes a transition will there be an emission of a photon. There are relativistic corrections to various energy levels as one goes up to higher orbital states, such as d and f orbitals. This certainly would affect the nature of the energy spectra that one would obtain. However, I don't think this is what you're asking for.

If you start confusing how "atoms" behave with what you notice from the bulk solid, then you'll get into trouble very quickly. Solid state physics is not identical to atomic/molecular physics. That's why they are two separate areas of study.

Zz.
http://www.fourmilab.ch/documents/golden_glow/"

<unfortunate commented deleted by pervect>
 
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  • #13
fourdoughnut said:
http://www.fourmilab.ch/documents/golden_glow/"

<unfortunate commented deleted by pervect>

But that article points to an atomic transition, no? The 4d to 5s, and the 5d to 6s are all transitions that in turn emits light. So it has nothing to do with the "orbit" itself that emits such light.

Zz.
 
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  • #14
ZapperZ said:
But that article points to an atomic transition, no? The 4d to 5s, and the 5d to 6s are all transitions that in turn emits light. So it has nothing to do with the "orbit" itself that emits such light.

Zz.

Really!, I'm so, so totally impressed by your outstandingly rich comprehension of things ... and I'm not just saying that.


:smile:
 
  • #15
fourdoughnut said:
Really!, I'm so, so totally impressed by your outstandingly rich comprehension of things ... and I'm not just saying that.


:smile:

If you're trying to be cute, then cut it out, because it isn't working.

You will note that I was not the only one who read your original post and deduced that you were implying an electron in an orbital ("transiting" around the nucleus) was radiating. Now I'm not sure why you decided to suddenly turn this into this tone when I was trying to get a clarification out of that issue, but if you don't cut it out, this thread is done.

Zz.
 

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