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Electronic Configuration Question

  1. Dec 19, 2004 #1
    How come the valance electrons of MO is [KR]5s^1 4d^5 and not

    [KR]5s^2 4d^4
  2. jcsd
  3. Dec 19, 2004 #2
    Because of the extra stability associated with a half-filled d-orbital. See http://itl.chem.ufl.edu/2045/lectures/lec_11.html [Broken].

    Scroll down to about half way where you see 'exchange' in blue; the configuration charts below that should be helpful as well.

    PS: Be careful with your notation; the elements MO and KR do not exist, and should be written as Mo and Kr to denote the elements you speak of.
    Last edited by a moderator: May 1, 2017
  4. Dec 20, 2004 #3
    Thank you, Sirus.

    That makes sense, but how would I predict such a thing?
  5. Dec 20, 2004 #4
    All half filled and full filled orbitals have extra stability.So much that the electron from s orbital may go to the inner orbital.check out e config of Cr,Cu etc.
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