What Quantum Numbers Define a Hydrogen Atom's State with No Angular Dependence?

AI Thread Summary
The quantum numbers defining the state of a hydrogen atom with no angular dependence are n, l, and m. The energy level is represented by n, while l and m correspond to the total orbital angular momentum and its z component, respectively. For a wavefunction with no angular dependence, the only spherical harmonic is Y_0^0, leading to the conclusion that n can be any integer, while both l and m must equal zero. The discussion also touches on the distinction between the spatial and spin parts of the wavefunction, suggesting that the exercise likely focuses solely on the spatial aspect. Overall, the answers provided are correct, with the key quantum numbers being l = 0 and m = 0.
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Homework Statement



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What quantum numbers are used to define state of hydrogen? The wavefunction has no angular dependence. Find the values of all the angular momentum quantum numbers for the electron.

Homework Equations


The Attempt at a Solution



The numbers are n, l and m.

n: Energy level
l(l+1): Eigenvalues of total orbital angular momentum
m: z component of orbital angular momentum

The complete wavefunction is given by: ##\psi = u_n^l Y_l^m##.

Thus the only spherical harmonic that doesn't have angular dependence is ##Y_0^0 = \sqrt{\frac{1}{4\pi}}##.

Thus the wavefunctions are ##\sqrt{\frac{1}{4\pi}}u_n^0##.

Thus n = any integer, l = 0, m = 0.

I'm slightly bothered by the term 'spatial part' of the wavefunction.
 
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"Spatial part" as opposed to "spin part". The exercise probably doesn't want you to worry about spin (my guess -- change that if you just finished a chapter on spin...)
 
BvU said:
"Spatial part" as opposed to "spin part". The exercise probably doesn't want you to worry about spin (my guess -- change that if you just finished a chapter on spin...)

We learn about the gross structure of Hydrogen, which ignores spin as the Hamiltonian is the KE of the nucleus and electron, and the potential energy.

Are my answers right then?
 
I would say yes. A nitpicker would argue n isn't a quantum number for angular momentum. In that case the answer is: l = 0 and m = 0
 
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