Figure 3 A packing diagram of (I) viewed down the c axis. Dashed lines represent hydrogen bonds. Atoms labelled with the suffixes i, ii, and iii are at symmetry equivalent positions (-x + 1, -y + 1, -z + 1), (x, -y + [{3\over 2}], z - [{1\over 2}]) and (-x + 2, y + [{1\over 2}], -z + [{3\over 2}]), respectively.  [article HTML]