Eigen values for a state and spherical harmonics

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Homework Statement



The complete wavefunction for a particular state an atom, is Si(r,theta,phi)=Ne^(-Zr/a_0)(Z/a_0)^3/2sqrt(1/4pi). What is the eigenvalue Lz for this state?

Homework Equations



see above

The Attempt at a Solution



This is the last one that I'm having trouble with. I have no idea how to start it. Just some pointers on how to begin would be awesome...
 
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The hydrogenic wavefunctions are of the form [itex]\psi(r,\phi,\theta)=R_{nl}Y_l^m[/itex]. You've been given the wavefunction
[tex]\psi = N r^2 e^{-\frac{Zr}{3a_0}}\sin^2 \theta e^{2i\phi}[/tex].

Identify the pieces and see if you can identify what n, l, and m are for this state.
 
Okay, so since Rn,l=2(Z/a0)3/2 e-Zr/a0, it means that the first part of the wavefunction is R and the second part is Y?

I know that Y0,0=Sqrt(1/4pi)
which fits the equation except for the constant out front.

This means that l=0. The first R for which l=0 is R1,0=2* e^(-Zr/a0)(Z/a0)3/2

So, if N=1/162sqrt(pi) *(Z/a0)7, then this wavefunction is R1,0Y0,0

This means that it is in the state |1,0,0>
 
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Good work. Now learn how the quantum numbers n, l, and m relate to Lz. (You should also know how they relate to other observables, like the energy and total angular momentum, though you don't need to know that for this particular problem.)