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

Homework Help: Fock operator for closed shell system

  1. Jan 9, 2007 #1

    The Fock operator for a closed system is given by

    f = H(core) + sum (2*f - k)

    where f is the Coulomb operator and k is the exchange operator. The summation goes from 1 to N/2. My questions is why is the summation to N/2 and why does one have to multiply the Coulomb operator by 2?

    Thanks in advance

    Best regards
  2. jcsd
  3. Jan 9, 2007 #2
    N/2 is due to each orbital has to electrons hence 2*Coulombic.
  4. Jan 9, 2007 #3


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Correct. The spatial part of the single-particle wavefunctions for the two electrons in the same orbital are identical.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook