Cherry Emerson Seminar Series
Prof. Nick Turro, Columbia University

Supramolecular Chemistry to Superdupermolecular Chemistry

During the last half of the 20th century, great advances were made in molecular chemistry, for which the key intellectual unit is the strong, intramolecular covalent bond. The last two decades of the 20th century saw the emergence of the field of supramolecular chemistry, for which the key intellectual unit is the weak, intermolecular non-covalent bond. A signature of supramolecular chemistry is the inability to understand chemical processes based only on molecular structure and covalent bonds, i.e., on needs to consider the intermolecular environment and its effect on molecular processes. A number of examples of organic photochemistry resulting from the supramolecular control of radical pair reactions will be presented. What is the next step beyond supramolecular chemistry, i.e., what sort of chemistry will be termed "superdupermolecular chemistry?" It is proposed that this term can be applied to chemistry that depends not only on electrostatics that determine the strength of covalent and non-covalent bonds, but those that can be dominated by magnetic effects. These magnetic effects are associated with the influence of electron spins and nuclear spins on chemical processes. Examples of magnetic effects on the geminate radical pairs, on the oH2 to pH2 conversion and on electonic energy transfer will be described.

For more information contact Becky Shaner.