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Fermi-Dirac distribution

  1. Apr 18, 2015 #1
    Hi all,

    The probability that a state is occupied means :

    1) Fully Occupied by 2 electrons Spin up and Spin down
    2) Occupied by 1 electron only .

  2. jcsd
  3. Apr 18, 2015 #2


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    Staff: Mentor

    It depends how state is defined :-p

    Sometimes, state is taken to be "energy level," meaning that it has a degeneracy of 2, as the first case you mentioned. Sometimes, state refers to the actual quantum state, in which case the Pauli exclusion principle makes it a one-electron state.

    You basically have to pay attention to what the author is saying (or worse, is implying).
  4. Apr 18, 2015 #3


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    Science Advisor
    Homework Helper

    Probably the term orbital or (spatial) energy eigenfunction better replaces the "state" in the first point.
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