Chapter 9: How Laminar Zirconium Phosphates Can Make Organic Molecules Display New Behavior and Properties at the Supramolecular Level in the Solid State

Many years ago Feynman, the Nobel laureate, made the query “What would the properties of materials be if we could really arrange the atoms (molecules) the way we want them?” Since then Chemistry, Physics, Engineering, and even Biology, have broken boundaries in pursuing of Feynman's ambition. Yet, half a century has passed since his qualm and “fortunately” the once-and-for-all solution to this problem still looks out of immediate reach. Despite all the smart accomplishments in the fields of Supramolecular Chemistry (“chemistry beyond the molecule”) and Crystal Engineering, the finding of new materials is as yet, for the time being, quite open a field that, no doubt, will allow for many serendipity-driven discoveries. Therefore, the design of porous solids of controlled molecular geometry for various applications is a challenge of enormous technological and scientific importance. The placing of organic molecules between the layers of certain inorganic salts leads to sturdy, solid materials where the “act of confinement” makes the organic molecules change their properties or even display new ones at the supramolecular level. A representative coverage of the literature in this field will be reviewed. Past and ongoing results of our research group concerning the chemistry of metal phosphates/phosphonates will be detailed in relation with the following topics: molecular recognition, chemically driven porosity changes, chiral memory and supramolecular chirality, luminescence signaling, photoinduced electron-transfer processes, gas storage, and confinement of drugs.