Wavefunction of ionized hydrogen electron

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Discussion Overview

The discussion revolves around the ionization of the electron in a hydrogen atom, specifically focusing on the wavefunction characteristics as the quantum number increases. Participants explore the nature of bound and unbound states, the behavior of wavefunctions, and the mathematical representation of these states.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants argue that there is no specific point at which the electron becomes ionized, as there are an infinite number of bound states.
  • It is suggested that even as the quantum number ##n \rightarrow \infty##, the energy remains finite, allowing for the possibility of the electron being unbound, with its wavefunction resembling a scattering state.
  • Questions are raised about the behavior of the angular component of the wavefunction during ionization, with responses indicating that the nature of ionization affects this component.
  • Participants inquire about how to demonstrate that the radial wavefunction becomes a sine wave as ##n## approaches infinity, leading to discussions about the conditions for bound and unbound states.
  • Some assert that for energies below 13.6 eV, the wavefunction is a product of a Laguerre polynomial and a decaying exponential, while for energies above 13.6 eV, the solutions are sines as ##r \rightarrow \infty##.
  • There is contention regarding the form of the unbound radial wavefunctions, with some stating they are not sine waves and questioning what their actual form is.
  • One participant expresses frustration over the lack of effort in understanding the topic, emphasizing the need for careful reading and research.

Areas of Agreement / Disagreement

Participants exhibit disagreement on the nature of the wavefunctions for unbound states and the conditions under which they transition from bound to unbound states. The discussion remains unresolved regarding the exact mathematical representation of these wavefunctions.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about the energy levels and the mathematical proofs for the wavefunctions, which remain unresolved.

Physicsman88
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TL;DR
When you solve the schrodinger equation and get the wavefunctions for hydrogen is there a point where the quantum number becomes so high the electron gets ejected and breaks free. If so what would the wave function look like
At what point does the electron become ionized in the hydrogen atom solution
 
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There is an infinite number of bound states, so no, there is no "point where the quantum number becomes so high the electron gets ejected and breaks free."

That said, even as ##n \rightarrow \infty## the energy remains finite, so it is possible to have an electron no longer bound to the nucleus. Its wave function then looks like a scattering state, which is basically an oscillating sine wave, except close to the nucleus.
 
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DrClaude said:
There is an infinite number of bound states, so no, there is no "point where the quantum number becomes so high the electron gets ejected and breaks free."

That said, even as ##n \rightarrow \infty## the energy remains finite, so it is possible to have an electron no longer bound to the nucleus. Its wave function then looks like a scattering state, which is basically an oscillating sine wave, except close to the nucleus.
What happens to the angular component of the wavefunction when the electron gets ionized.
 
DrClaude said:
There is an infinite number of bound states, so no, there is no "point where the quantum number becomes so high the electron gets ejected and breaks free."

That said, even as ##n \rightarrow \infty## the energy remains finite, so it is possible to have an electron no longer bound to the nucleus. Its wave function then looks like a scattering state, which is basically an oscillating sine wave, except close to the nucleus.
How do you show that as n goes to infinity The radial wavefunction becomes a sine wave
 
Physicsman88 said:
What happens to the angular component of the wavefunction when the electron gets ionized.
That depends on how ionization takes place.

Physicsman88 said:
How do you show that as n goes to infinity The radial wavefunction becomes a sine wave
That's not what happens. For E < 13.6 eV, you have an infinite number of bound states with the wave function a product of a Laguerre polynomial and a decaying exponential. For E > 13.6 eV, the solutions are sines as ##r \rightarrow \infty##, like what is obtained for a (finite) square potential, as found in most QM textbooks.
 
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How do you mathematically show that the solutions are sines for the radial wavefunction when E>13.6 eV like is there a proof for it
 
Physicsman88 said:
How do you mathematically show that the solutions are sines for the radial wavefunction when E>13.6 eV like is there a proof for it
Since they aren't, you don't. They are sines for unbound particles in Cartesian coordinates.
 
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Vanadium 50 said:
Since they aren't, you don't. They are sines for unbound particles in Cartesian coordinates.
So if the unbounded radial wavefunctions arent sine waves what are they then
 
Physicsman88 said:
So if the unbounded radial wavefunctions arent sine waves what are they then
My slaves! Solve this equation for me!

Are you going to put in any effort at all? Seriously - if careful reading of replies is too much effort, and Googlinmg "wave equation in spherical coordinates" is too much effort, how do you expect to make any progress? We can't simply pour information into your head.

For an l=0 case, the wavefunction is of the form sin(kr-wt)/r.
 
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The unbound hydrogen states are briefly mentioned on page 231 of these notes.
 
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