Comment on the article Symmetry and chirality in crystals

In a recently published paper, Nespolo & Benahsene [J. Appl. Cryst. (2021), 54, 1594–1599] state that `chiral crystal structures from achiral molecules can occur in 28 types of space group having screw axes np, with p ≠ n/2, not in any Sohncke type of space group'. It is argued that chiral crystal structures from achiral molecules, in fact, occur in all 65 Sohncke space groups.