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Lattice systems and group symmetries

  1. Apr 27, 2014 #1


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    Dear all,

    In Marder's Condensed matter physics, it uses matrix operations to explain how to justify two different lattice systems as listed in attachment.

    However, I cannot understand why the two groups are equivalent if there exists a single matrix S satisfying S-1RS-1+S-1a=R'+a'.

    Can someone help me to understand it? Thank you.
  2. jcsd
  3. May 6, 2014 #2
    I'm sorry you are not generating any responses at the moment. Is there any additional information you can share with us? Any new findings?
  4. May 7, 2014 #3


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    Marder is saying that if there is a linear map between the two lattice systems, then they are equivalent. The original system is defined by a Rotation (R) and a translation (a).

    The matrix S and its inverse are performing a similarity transformation (coordinate system change) on R, and also apply it to the translation.

    Marder then notes if there exists one such linear transform, then there exists a family of them.

    Personally I found Marder too abstract for my taste, though the group theoretical approach to crystallography is very powerful. But most of the math is not very difficult - it just appears dense because of the writing style.
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