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What are the quantum numbers (n, L, J)?

  1. May 30, 2015 #1
    1. The problem statement, all variables and given/known data

    I'm supposed to find the quantum numbers (n, L, J) for the first 3 energy levels in Iridium (Z=77), given that the first 4 ionization energies are ##76.1, 13.4, 12.8, 11.2 keV##.



    2. Relevant equations


    3. The attempt at a solution
    I know that the electronic configuration is ##[Xe] 4f^{14} 5d^7 6s^2##.
    I suppose lowest level is ##n=6, l=0, S=0,J=0##.
    Is the next level ##6s^1 6p^1##?
     
  2. jcsd
  3. May 31, 2015 #2
    I want to help you but I didnt understand your question.Example you said "first 3 energy levels" you know first energy level is n=1 l=0 and J=0 so can you be more spesific.I might be understand your question false too.
     
  4. May 31, 2015 #3
    How can lowest energy level be 1 when the outermost orbital is at ##6s^2##?
     
  5. May 31, 2015 #4
    First three energy means n=1 n=2 and n=3 but lowest energy is ##6s^2##
     
  6. May 31, 2015 #5
    Ok, so n = 1,2,3,4. What are the L and J for each?
     
  7. May 31, 2015 #6
    Here you can find everything
     

    Attached Files:

  8. May 31, 2015 #7
    Thanks for your input, but you just said first 3 levels are n=1,2,3 and that directly contradicts what's in the picture.
     
  9. May 31, 2015 #8
    Yes I didnt understand your question and I assumed this
     
  10. May 31, 2015 #9

    blue_leaf77

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    I think you should check again the problem, you said first 4 ionization energies but the values you gave stands in keV range which doesn't make sense for large atom like Ir, plus they are in the order of lowering values, which should be the other way around. There is a good discussion about many electron atoms in Physics of Atoms and Molecules by Bransden and Joachain, you might want to check this out.
     
  11. May 31, 2015 #10
    The question is here:

    Untitled.png
     
  12. Jun 1, 2015 #11
  13. Jun 2, 2015 #12
    I want to help.Is there any equation between energy level and n I found this 02e69956dddad4d7391957cb04495e37.png but I am not sure
     
  14. Jun 2, 2015 #13

    blue_leaf77

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    I have found the answer to your question in Google.com.
     
  15. Jun 2, 2015 #14
    then post the url
     
  16. Jun 2, 2015 #15

    blue_leaf77

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    The forum rule forbids helpers to give directly the final answer. Very unfortunate that I can't help with physical arguments.
     
  17. Jun 2, 2015 #16
    Send me a message I can help him maybe
     
  18. Jun 2, 2015 #17
    Electron binding energy means electron ionization energy.Now there wrote most tightly,it means we have to give a lot of energy to ionize electron.Think this way If Ir has one electron then we should use this formula 02e69956dddad4d7391957cb04495e37.png to find binding energy of electron.Put the values and you will find n there.Find it and tell me the answer then I will explain the other energies and you will understand the question.
     
  19. Jun 17, 2015 #18
    We can't assume that, as each level has a shielding effect such that ##E_n = -hcR_{\infty}\frac{(Z-\sigma_n)^2}{n^2}##.
     
  20. Jun 17, 2015 #19
    Ok, I think I got it. Are the first 4 energy levels ##1s^2, 2s^2, 3s^2, 4s^2##?
     
    Last edited: Jun 17, 2015
  21. Jun 17, 2015 #20

    blue_leaf77

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    For such heavy atom, I suspect the relativistic effect which manifests itself in the coupling between orbital and spin angular momenta will be too big to be neglected, due to which the J quantum number may have to appear in certain form in the notation of the states.
     
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