Figure 1 (a) The asymmetric unit with H atoms omitted for clarity. C atoms in molecule A (including the associated acetonitrile ligand) are shown in light grey colour, as opposed to C atoms in molecule B which are dark grey. O atoms in perchlorate ion D, coordinating to molecule A, appear in orange, while O atoms in perchlorate ion E close to B are dark red. Perchlorate ions F and G are depicted here as light green and green spheres, respectively, to reduce overlap with A and B. (b) Complex A with perchlorate D. One pyridine ring has been shaded. (c) Complex B with perchlorate E. The indicated distances are Zn1B...O1E = 3.077 (3) Å and Zn1B...O2E = 3.827 (3) Å, which may be compared to 2.310 (3) Å for O1D-Zn1A. Displacement ellipsoids in (b) and (c) are shown at the 50% probability level with H atoms as spheres of arbitrary size.  [article HTML]