What causes an electron to return to its ground state?

Click For Summary

Discussion Overview

The discussion revolves around the mechanisms that cause an electron to return to its ground state after being excited. It touches on concepts from quantum electrodynamics (QED) and the nature of atomic transitions, particularly in hydrogen and other elements.

Discussion Character

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

Main Points Raised

  • One participant expresses curiosity about the fundamental reasons behind an electron's return to its ground state after excitation, questioning the role of the positively charged nucleus and energy loss mechanisms.
  • Another participant introduces the concept of spontaneous emission, referencing QED and explaining how vacuum fluctuations contribute to the transition of electrons from excited states to ground states.
  • A participant acknowledges the complexity of the topic and suggests that further understanding may require advanced study, such as in graduate school.
  • Another participant raises a related question about the names of spectral transitions (Lyman, Balmer, Paschen) and whether they apply only to hydrogen or to other elements as well.
  • One participant clarifies that the named transitions are specific to hydrogen, noting that other elements do not have the same theoretical clarity due to the complexity of their atomic structures.

Areas of Agreement / Disagreement

Participants express varying levels of understanding and interest in the topic, with some focusing on hydrogen and others indicating uncertainty about the applicability of spectral transition names to other elements. The discussion remains unresolved regarding the broader implications for other atomic systems.

Contextual Notes

Limitations include the complexity of atomic systems beyond hydrogen, which affects the ability to theoretically determine emission spectra for other elements. The discussion also reflects varying levels of familiarity with quantum mechanics and related concepts.

Who May Find This Useful

Readers interested in quantum mechanics, atomic physics, and the specifics of atomic transitions, particularly in hydrogen and other elements, may find this discussion relevant.

Wheelwalker
Messages
42
Reaction score
1
I've recently realized I have completely taken for granted that electrons simply tend to be found in their ground state. I want to understand fundamentally what is causing the electron to drop back to its ground state. It feels a force from the positively charged nucleus, but if it was given exactly enough energy to hop up into an excited state, how does it lose that energy and consequently get forced back "down"?
 
Physics news on Phys.org
Its the process of spontaneous emission which requires QED to explain:
http://en.wikipedia.org/wiki/Spontaneous_emission
'In quantum electrodynamics (or QED), the electromagnetic field has a ground state, the QED vacuum, which can mix with the excited stationary states of the atom (for more information, see Ref. [2]). As a result of this interaction, the "stationary state" of the atom is no longer a true eigenstate of the combined system of the atom plus electromagnetic field. In particular, the electron transition from the excited state to the electronic ground state mixes with the transition of the electromagnetic field from the ground state to an excited state, a field state with one photon in it. Spontaneous emission in free space depends upon vacuum fluctuations to get started.'

Thanks
Bill
 
Thanks Bill. Looks like this will have to wait for grad school!
 
Bill, since you're so helpful, in a kind of related question.

I'm reading about all of those transitions, lymann, balmer, paschen, and more.
Everytime I look it up it always begins with: "in the hydrogen emmison spectrum..."

Are these names only for hydrogen? What about the other elements? Do they have different names?
 
This is more physical chemistry stuff - I am more of the mathematical physics bent.

But all the above are for Hydrogen atoms and are the only ones I know of - and even then I had to look up paschen. They certainly exist, but its not something I am into.

Sorry mate - must leave it up to someone else.

Thanks
Bill
 
Only the H-atom can be fully solved in QM, since it's a 2-particle system. For the other atoms, you can't fully solve the spectral problem of the Hamiltonian, hence you can't determine the emission spectrum theoretically => the name of the transitions are only for the H-atom.
 
  • Like
Likes   Reactions: 1 person

Similar threads

  • · Replies 26 ·
Replies
26
Views
5K
  • · Replies 3 ·
Replies
3
Views
7K
  • · Replies 12 ·
Replies
12
Views
1K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 16 ·
Replies
16
Views
4K
  • · Replies 7 ·
Replies
7
Views
4K
  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 15 ·
Replies
15
Views
4K