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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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Prof. C. David Sherrill, Georgia Tech
The Fundamental Nature of Pi Interactions
Weak interactions, such as the noncovalent interactions governing drug binding and the structures of organic crystals, are very challenging to understand. Experimentally, these interactions are often seen in complex environments, where it can be difficult to pick out only the interaction of interest. Theoretically, they require very accurate quantum-mechanical modeling for reliable results. Definitive theoretical investigations of π-π, alkyl-π, and sulfur-π interactions which elucidate the strength, geometrical preferences, and fundamental nature of these prototype biomolecular interactions will be presented. In particular, it is shown that the current paradigm for understanding π- π interactions, which emphasizes electrostatic interactions, fails qualitatively in light of high-level quantum-mechanical results. Applications to SH/π interactions in proteins and the first ``chemical accuracy'' computation of the lattice energy of an organic crystal (benzene) will be presented. Advances in theoretical methods for non-bonded interactions in larger molecules will also be discussed.
