Reflections with phase angle 0 or π in noncentrosymmetric space groups

The imaginary parts of structure factors in centrosymmetric space groups disappear so that the phase angle of every reflection is either 0 or ir. On the other hand, the phase angles of reflections in noncentrosymmetric space groups can have any value between 0 and 2 pi. However, some reflections in the noncentrosymmetric space groups under certain conditions behave just like those in the centrosymmetric space groups, which might help to solve the so-called crystallographic phase problem. Reflections with phase angle of either 0 or pi in 157 noncentrosymmetric space groups extracted from International Tables for X-ray Crystallography (1979), Vol. I (Birmingham: Kynoch Press) are tabulated.