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Homework Help: Possible Values for Total Angular Momentum

  1. Mar 15, 2010 #1
    1. List all the possible values of total angular momentum for the following

    1. 3P
    2. 2D




    2. Relevant equations
    j = s + l


    3. The attempt at a solution
    is this problem as simple as, for 1.
    for 3p, n = 3, l = 0,1,2
    since it's a p orbital, l = 1
    thus j = l + s, all possible values are 3/2, and 1/2
    but for 2d, i just dont know... is this theoretical? there are no d orbitals at the n = 2 level right? or am i misinterpretting the symbols?
     
    Last edited: Mar 15, 2010
  2. jcsd
  3. Mar 15, 2010 #2
    The 3 in the superscript notation for problem (1) I believe stands for 3 = 2S+1, so the spin 'S' is equal to 1.
     
  4. Mar 16, 2010 #3
    ahh! then for (1)
    does that mean S = 1, and since it is a P orbital it is L = 1
    Hence J = 2.

    Is this all the values that J can attain?"
     
  5. Mar 16, 2010 #4
    J can equal |L-S|, |L-S|+1, ... L+S-1, L+S

    So find the min and max J, and all values between them.
     
  6. Mar 16, 2010 #5
    ah!
    so for (1)
    does that mean J can equal 0 or 1
    and for (2) J = 5/2 or 3/2?
    is that all the values for J?
    Thanks for the help by the way!
     
  7. Mar 16, 2010 #6
    For (1), you said S=1 and L=1, so you have for the bounds of J... J = |1-1| = 0 and J = 1+1 = 2.

    So all possible values for J are 0, 1, and 2.
     
  8. Mar 16, 2010 #7
    oh ya, duh, my mistake, how about the 2nd one. the 2nd one is right though?
    5/2 and 3/2?
     
  9. Mar 16, 2010 #8
    Yes, that looks right.
     
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