When writing the basis of a molecule, and there are (for example in a square) 4 points which are all 1/4 covered, does it then matter which one of the four points you take to denote the basis? In more complex structures it is less obvious for me which one to take so I would like to be sure that it does not matter which one I choose.
I usually imagine shifting the unit cell slightly, so that none of the borders overlap with the atoms. Another way is to check that you don’t have basis coordinates that differ by 1 (so a lattice vector) along any direction. For example, (1/2, 0, 0) and (1/2, 1, 0).