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WE theorem to evaluate matrix elements

  1. Dec 3, 2008 #1

    In my work I use the WE theorem to evaluate matrix elements. F being the total spin and m the projection onto the z-axis, I am using:

    <JIFm|r_(-q)|J'IF'm'>=(-1)^(F'+m'-m)<Fm1q|F'm'>sqrt(2F+1)sixj(F, F', 1:J',J,I)<J'||r||J>

    I have a problem with the (-1)^ part which I suspect to be wrong, but have not been able to find a formula to compare a check. Am quite sure the rest is right. Could somebody help and tell what should be in the exponent?
  2. jcsd
  3. Dec 4, 2008 #2
    Re: Wigner-Eckart

    I have the theorem as:

    [tex]<\tau J M|T_q^{(k)}|\tau' J' M'> = {1 \over {\sqrt{2J+1}}}<\tau J ||T^{(k)}||\tau' J'><J' k M' q| J M>[/tex]

    where [tex]<\tau J ||T^{(k)}||\tau' J'>[/tex] is the reduced matrix element.

    Unfortunately I couldn't make head nor tail of the function you're trying to use. Maybe I'll've been of some help. Either way, this has been here for a couple of days with no reply, so maybe this will help the discussion.
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