Molecular tectonics: geometry and energy based analysis of coordination networks

Abstract

The combination of the bis-monodentate tecton 1 based on the fluorene skeleton and bearing two pyridine units as coordinating sites with HgCl₂ acting as a metallatecton leads to a 1-D coordination network in the crystalline phase as demonstrated by single crystal X-ray diffraction. When considering only geometrical features of the organic and metallic tectons, the generation of the network may be described as resulting from interconnection through Cl–Hg interactions of consecutive metallamacrocycles formed between two tectons 1 and two HgCl₂ complexes. However, the analysis of the solid by energy criteria evaluated using the PACHA algorithm reveals that the bridging (Hg–Cl–Hg) process participates for only 19% of the overall energy whereas the π–π interaction between fluorene units contributes up to 60%. Thus, when taking into account both μ-bridging process and π–π interactions, the overall system may be described as a 2-D hybrid metallo-organic network.