I'm working on a problem where I have to find the little co-group and star of two wave vectors for a diamond structure (space group 227). I know I have to act on the vector by the symmetry operations in the group (perhaps only the ones in the isogonal point group, O(adsbygoogle = window.adsbygoogle || []).push({}); _{h}?) and see if it remains the same or at a point in the reciprocal lattice. My problem is that i dont know how to do it explicitly. How do I find the matrix representations of the operations?

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# Finding the star of a wave vector using group theory

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