Isostructurality Based on Interchangeability of Supramolecular Synthons

The development of the supramolecular synthon concept from pattern recognition considerably simplifies the analysis and design of complicated crystal structures [9], as topological features and useful empirical rules can be derived by critical examination of the wealth of crystallographic information documented in structural databases [10], 

The building blocks (H20-C404 -H20) and (H20-Br )2 in the host structures of 1 and 2, respectively, can be regarded as equivalent synthons of compatible geometry and 

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