Host guest chemistry & Supramolecular Networks
The inclusion of small guest molecules in open framework of a host molecule constitutes a host guest compound. Cavitands, or molecular host compounds with intra-molecular cavities; Clathrands are hosts with extra-molecular cavities that result from the aggregation of more than one molecule are two major categories of host guest chemistry. The rational construction of novel open-framework of organic solids is of particular interest because of their diverse applications such as chemical separation, reactions and catalysis in a microcavity, and for electro-optic, nonlinear and magnetic materials. Metal-ligand coordination bonding is extensively used in the modular assembly of extended porous solids and low density frameworks. Tuning the pore size and shape and controlling the hydrophobic/hydrophilic nature of the host cavity are major endeavors in crystal engineering.