Figure 2
Hydrogen bonding in (I). The two crystallographically distinct hydrogen bonds produce groups of four hydrogen-bonded molecules around the inversion centers located at the corners of the unit cell. Atoms or molecules marked with an asterisk (*), hash (#), or caret () are at the symmetry positions (x, y − 1, z), (−x, 1 − y, 2 − z), and (−x, −y, 2 − z), respectively; the plus (+) represents an inversion center. |