Figure 4
Section κ = 180° for the self-rotation function of a DAOCS crystal with twin fraction 0.30 (data from 7 to 5 Å) using the program POLARRFN (Collaborative Computational Project, Number 4, 1994) show a twofold axis in addition to the R3 symmetry. The twofold axis is perpendicular to the crystallographic threefold axis and is equivalent to the twofold axis in the higher symmetry space group R32. Since the size of the unit cell did not allow 18 molecules, non-crystallographic symmetry or the higher symmetry space group could be ruled out, identifying the axis as the twin operator. |