X-ray diffraction for 2-D crystal

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Is it possible to perform x-ray diffraction for 2-D crystal like Graphene? If poossible how does the bragg interference criteria look like here?

 

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Yes it is possible. In the reciprocal space you will have rods perpendicular to the 2D-plain. Your Bragg peaks will a appear at the intersection of the Ewald sphere with the rods. For instance if you direct the incident beam perpendicular to the surface and detect the backward scattering you will detect (hk) reflections at some 2theta angles < 180. The angle will depend on vertical detector position in this case.