Home > Supramolecular chemistry

A supramolecular assembly is a multi-component system of atom, ion, and/or molecule which are held together by non-covalent interactions such as hydrogen bonds, van der Waals force , pi-pi interactions, and electrostatic effects. The latter mode of bonding is particularly important for assemblies involving metal ions. These various bonding interactions are far weaker than covalent bonding (which are the kind of bonds which hold molecules together) therefore supramolecular assemblies are usually far less stable than molecular compounds (for example, they can be more suceptible to breaking apart at high temperatures or if they are mixed with acid).

How are supramolecular assemblies formed? The most straightforward method is to use self-assembly techniques, which is to say that you mix your components under given set of conditions (solvent, temperature, pH etc.) then cross your fingers and hope for the best. Of course, most chemists try to approach things a little more rationally than this and attempt to design synthetic routes based on predicted interactions between the various components of the mixture. Happily, self-assembly processes often converge on a single product out of the coutless possible combinations of your starting materials. This product is formed because it is the thermodynamically most stable arrangement of the constituent entities. Chemists get very excited about self-assembly as they see it as being a very efficient and reliable method for the "bottom-up" synthesis of new materials (as opposed to current "top-down" methods for producing, for example, computer chips).

During the self-assembly process, inevitably some of your starting materials will go down the 'wrong track' towards other products. It therefore turns out to be very useful that the bonding interactions between the compenents of these assemblies are quite weak. This is because the 'wrong' products are easily dis-assembled and the components can quickly recombine in the 'right' way to form the most stable assembly. This 'reversibility' is one of the key features of supramolecular synthesis and it contrasts with the situation in conventional molecular synthesis involving covalent bonds. In molecular synthesis, a reaction which goes down the 'wrong pathway' often ends up at a dead end and the material which is formed must in the end be separated from the desired product.

One of the major goals of supramolecular chemists is the syntheis of supramolecular assemblies which have new functions that cannot appear from a single molecule or ion. These functions are based on the novle magneticIn physics, magnetism is a phenomenon by which materials exert an attractive or repulsive force on other materials. Some well known materials that exhibit easily detectable magnetic properties are iron, some steels, and the mineral lodestone; however, all properties, light responsiveness, catalytic activityIn chemistry and biology, catalysis is the acceleration of the rate of a chemical reaction by a substance, called a catalyst, that is itself unchanged by the overall reaction. A common misunderstanding is that catalysis "makes the reaction happen": that t, fluorescenceultraviolet light in vials containing various sized cadmium selenide (CdSe) quantum dots. Fluorescence is a luminescence, i. optical phenomenon in cold bodies, in which a molecule absorbs a high-energy photon, and re-emits it as a lower-energy (longer-wav, redoxThe most fundamental reactions in chemistry are the redox processes . The term redox process accounts to all processes in which atoms have their oxidation number changed. This can be a simple redox process, such as the combustion of carbon by oxygen to yi propeties etc of supramolecular systems. These useful properties may lead to the application of these assemblies as - and this is a list of random examples - high-tech sensors for pollutants in air or water, compact information storage devices for next-generation computers, as high-performance catalystsIn chemistry and biology, catalysis is the acceleration of the rate of a chemical reaction by a substance, called a catalyst, that is itself unchanged by the overall reaction. A common misunderstanding is that catalysis "makes the reaction happen": that t in industrial processes, or as contrast agents for CAT scansComputed axial tomography (CAT computer-assisted tomography computed tomography CT or body section roentgenography is the process of using digital processing to generate a three-dimensional image of the internals of an object from a large series of two-di. Supramolecular chemistry is intimately related to nanotechnologyNanotechnology as a collective term refers to technological developments on the nanometre scale, usually 0. One nanometre equals one thousandth of a micrometre or one millionth of a millimetre. The term sometimes applies to any microscopic technology. and many promising nanotech devices are based on the principles of supramolecular chemistry.