Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Spin orbit coupling/orbital degeneracy

  1. May 20, 2009 #1
    disregarding the hyperfine structure and the lamb shift for the moment, spin orbit coupling says that 2S1/2 and 2P1/2 have the same energy. do 2S0 and 2P0 have the same energy?

    if 2P splits into 3/2 and 1/2 does the 3D orbital split into 5/2, 3/2, and 1/2 and the 4F orbital into 7/2, 5/2, 3/2, and 1/2? google gets plenty of hits but they only talk about 2P.


    this is just my own personal interest but you can move it to homework if you are so inclined.
     
  2. jcsd
  3. May 20, 2009 #2

    clem

    User Avatar
    Science Advisor

    The subscript1/2 is the total J=L+S (QM addition). That limits J to L+1/2 and L-1/2.
    There is no 0 subscrlpt for one electron.
    A D orbital (L=2) can have only 3/2 or 5/2.
    An F orbital (L=3) can have only 5/2 or 7/2.
    The G...
     
  4. May 21, 2009 #3
    thank you for responding.

    the web says that those numbers only hold if the number of electrons is odd. I was wondering what happens if the number of electrons is even. that is why I asked about 2S0.
     
  5. May 21, 2009 #4

    malawi_glenn

    User Avatar
    Science Advisor
    Homework Helper

    "the web says" is a pretty non specific statement, why not state where you read it? Maybe you have misunderstood something?

    Which atoms are you considering?

    nLj referes to single electron-orbitals, a single electron orbital can not have j = half integer. 2So does not exists as single orbital, are you suggesting 2So to be notation for what??
     
  6. May 21, 2009 #5
    because I read it on many sites. they all say the same thing. that the formula only works of odd number of electrons. I'll try to find the exact source.
     
    Last edited: May 21, 2009
  7. May 21, 2009 #6
    I know that the zeeman effect is different for even and odd and all the sites talk about 2P1/2 and 2S1/2. maybe I assumed it was different. if the number of electrons was even then why would the S orbital have spin 1/2?
     
  8. May 21, 2009 #7
    from the web:
    The nlj quantum numbers are, then, again appropriate for a single electron outside closed subshells.

    so what do I use for closed shells or nonclosed shells with more than one electron? especially for calculating fine structure.
     
  9. May 21, 2009 #8
    https://www.physicsforums.com/showthread.php?t=114363

    unperturbed hydrogenic wavefunctions?
     
  10. May 24, 2009 #9
    http://www.pha.jhu.edu/~rt19/hydro/node9.html [Broken]

    http://www.pha.jhu.edu/~rt19/hydro/img194.gif [Broken]
     
    Last edited by a moderator: May 4, 2017
  11. May 24, 2009 #10

    malawi_glenn

    User Avatar
    Science Advisor
    Homework Helper

    yes what about them, and what about the picture? what do you want?
     
  12. May 24, 2009 #11
    I thought others might find it helpful.
     
  13. May 24, 2009 #12

    malawi_glenn

    User Avatar
    Science Advisor
    Homework Helper

    but you explicit ask "unperturbed hydrogenic wavefunctions?"
     
  14. May 24, 2009 #13
    that was 3 days ago. I figured you just werent going to answer.

    I guess that 'unperturbed hydrogenic wavefunction' just means the simplified hydrogen model without taking spin-orbit coupling into account? or does it mean something else completely?
     
  15. May 24, 2009 #14

    malawi_glenn

    User Avatar
    Science Advisor
    Homework Helper

    yes, that is correct.
     
  16. May 24, 2009 #15

    nrqed

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    ?? L is an integer and S= 1/2 so j must be a half integer for a single electron orbital
     
  17. May 25, 2009 #16

    malawi_glenn

    User Avatar
    Science Advisor
    Homework Helper

    LOL correct, i did too many "not" in one sentence ;-) Sorry
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Spin orbit coupling/orbital degeneracy
  1. Spin orbit coupling (Replies: 1)

  2. Spin orbit coupling (Replies: 1)

  3. Spin-Orbit Coupling (Replies: 2)

  4. Spin-Orbit Coupling (Replies: 10)

Loading...