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What are Jacobi coordinates, and why are they useful?

  1. Jun 10, 2009 #1
    What are "Jacobi coordinates," and why are they useful?

    I am working on a quantum chemistry problem involving triatomic molecules. My advisor keeps talking about "Jacobi coordinates" and how they're a calculational convenience when it comes time to write out the Hamiltonian. Can someone describe them to me, and why they make life easier? I can't seem to find a good resource for this on the Web...
  2. jcsd
  3. Jun 11, 2009 #2


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    Re: What are "Jacobi coordinates," and why are they useful?

    Jacobi coordinates are coordinates for three bodies of equal mass, using the cm of two of them. The coordinates I like to use are
    The more common Jacobi coordinates divide by square roots to make equations more symmetric, but they get more complicated in practice.
    If one of the bodies has a different mass, then masses have to enter.
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