I've been struggling with what is probably a basic question about Bragg peaks, diffraction, and I guess geometric structure factors.
Basically, as I understand it, Bragg peaks depend on the symmetry of the system. We get them from constructive interference due to different planes of unit cells in the crystal. What I don't understand is why planes of atoms contained in those unit cells, which may have different (greater?) symmetry than the unit cells, cannot also give rise to Bragg peaks. In other words, why can't a sublattice be responsible for its own Bragg peaks?
I hope that makes sense, thanks.