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Double Counting

  1. Jun 13, 2014 #1
    Hi there,

    I'm not sure if someone here can help me because the topic is quite specific.
    In LDA+U Calculation one have to substract the Double Counting from the DFT functional. There are two main possibilities to do this:
    1.) Around Mean Field (AMF)
    2.) Fully Localized Limit (FLL)

    I found out, that theres a correction term to FLL due to non-collinearity and I ask myself if theres a correction term to AMF aswell. I searched in books, papers and the internet but didn't find anything about this topic.

    Maybe someone can help me.

    Thanks for your help!
  2. jcsd
  3. Jun 14, 2014 #2
    When you say subtract double counting, do you mean correcting the one electron self-interaction?
  4. Jun 15, 2014 #3

    yes i mean the correction of the one electron self-interaction. Sorry for that mad formulation!
    I found a paper (Physical Review B 67, 153106 (2003)) where the author wrote down the correction in terms of density matrices. But if I try to evaluate these formula for FLL DC (where I know the exact result, i.e. given in http://ftp.abinit.org/ws11/bousquet.pdf), I do not get the right double-counting correction.

    I will go on working on this problem today.
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