What part of the atom creates light?

[azzkika]

What part of the atom creates light??

what part of the atom is responsible for making light, and what particular action must it undergo in order to make light.

i have a basic understanding of electromagnetic wavelengths, and am curious as to how they are produced, and what occurs at the atomic level in order to produce and vary the wavelength/frequency

 

[cesiumfrog]

Do you have any understanding of the shapes of electron orbitals? Do you know what produces EM waves on the classical level?

 

[azzkika]

Do you have any understanding of the shapes of electron orbitals? Do you know what produces EM waves on the classical level?

i have no understanding of orbital shapes, i would guess EM waves are produced by the charge between electron and photon, but this is only a guess, and have no idea why hydrogen produces light when super heated in the sun, yet none when a cool gas on earth, or what variances at atomic level vary EM wavelength.

 

[cesiumfrog]

Look, I could try to simplify an explanation in layperson terms, but how would that help?

I ask certain questions and get certain answers, but then i get other answers that suggest the first answer was incomplete or plain wrong.

I suggest you pick up a textbook (on Electrodynamics, or on first year undergraduate physics, if you're not experienced with calculus yet). That is the path that will lead you to understanding the complete answers.

 

[Meir Achuz]

what part of the atom is responsible for making light, and what particular action must it undergo in order to make light.

i have a basic understanding of electromagnetic wavelengths, and am curious as to how they are produced, and what occurs at the atomic level in order to produce and vary the wavelength/frequency

Light is produced when a electron in the atom goes from an excited state of energy E_i to a state of lower energy E_f, emitting a photon of frequency f=(E_i-E_f)/h.

 

[ronjanec]

Clem just said what I have read to be true also. Could I just add that this is more than one photon emitted or a stream of photons that then travel in a wavelike up and down pattern away from the electron like I just mentioned in the what is light thread?

 

[granpa]

you shouldn't start with atoms. you should start with antennas.

 

[vanesch]

you shouldn't start with atoms. you should start with antennas.

Indeed, probably a classical picture is the easiest. You can picture an atom that makes a transition as an oscillating charge cloud, so as a tiny "antenna" that emits radiation with the frequency equal to the oscillation frequency of the charge.
Quantum-mechanically, there's less of a picture: you get an interaction between the atom (state jump) and the em field (photon count +1).

 

[Marty]

Indeed, probably a classical picture is the easiest. You can picture an atom that makes a transition as an oscillating charge cloud, so as a tiny "antenna" that emits radiation with the frequency equal to the oscillation frequency of the charge.

I wonder why you call this the classical picture. Is this not the quantum mechanical picture as given by the Schroedinger equation?

 

[vanesch]

I wonder why you call this the classical picture. Is this not the quantum mechanical picture as given by the Schroedinger equation?

Eh, probably too. I guess you can indeed take the superposition of say, a p_x and an s orbital, and that wavefunction, which is not a stationary state, will show an associated expectation value of current which will indeed oscillate and so on, and which will radiate classical EM radiation of *more or less* the right properties. However, I don't think you'd get out the correct "photon properties".
But that's usually not how things are seen on the QM level: one usually considers the interaction of the "atom system" with the "free QED field" through a coupling term. And that's harder to visualise.