Due to their versatile structural diversity and potential applications in different areas from catalysis to nonlinear optics self-assembled metal complexes have attracted considerable attention in crystal engineering andsupramolecular chemistry,controlling the architecture of self-assembled species influenced by the structure of ligands, coordination geometry of metal ions, counter-anions, and supramolecular interactions of the coordination compound with its surroundings.The spherical d10 configuration of Hg(II) is associated with a flexible coordination environment, thus the geometries of these complexes can vary from linear to octahedral or even distorted hexagonal bipyramidal, and severe distortions from ideal coordinationpolyhedra occur easily. Furthermore, due to the lability of d10 metal complexes, the formation of coordination bonds is reversible, which enables metal ions and ligands to rearrange during the supramolecular assembly to allow the formation of the thermodynamically most stable structure, by varying the coordination polyhedron and coordination number of the mercury atom. Consequently, mercury(II) can readily accommodate different kinds of coordination frameworks, using a variety of organic ligands along with different inorganic-organic bridging units. In order to further explore the structural chemistry of mercury(II) compounds with N-donor ligands, we undertook the systematic synthesis and structural characterization of Hg(II) complexes of a series of unsymmetrical Schiff base ligands. The goal of this study is to analyze the competition between anion and ligand HL (Scheme 1) for the coordination sites at the mercury(II) centre and to probe how the nature of the anion affects the crystal packing. Herein, we report the self-assembly and resulting structures of ninemercury(II) complexes containing three different Schiff base ligands (1–9). They have been characterized by different physicochemical measurements including single-crystal X-ray crystall
