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Hund's rule

  1. Nov 4, 2003 #1
    Does Hund's rule also apply when combining the angular momenta of electrons from shells with DIFFERENT quantum number n?
  2. jcsd
  3. Nov 14, 2003 #2

    Tom Mattson

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    I'm not sure of what you mean. Hund's rule does not have to do with "combining angular momenta", but rather with filling subshells.
  4. Nov 14, 2003 #3
    Suppose there are n electrons with angular momentum quantum numbers L1, L2, L3, ..., Ln. The total angular momentum L of the atom can be any number between the minimum and the maximum of all non-negative combinations +/- L1 +/- L2 +/- L3 ... +/- Ln (in steps of 1). Same about combinations of the spin (the spin quantum numbers of the single electrons are always 1/2) to the total spin S of the atom.

    Hund's rule says that the lowest-energy state among all the possible states is the state which has the greatest S and the greatest L (for that S).
  5. Nov 15, 2003 #4
    If it's true in two cases, it's true in all (in this case)

    Best wishes
  6. Nov 15, 2003 #5
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