Etude Experimentale De Linteraction Pi Pi Et Du Courant Hadronique Dans La Desintegration K Pi Pi E Nu

Author : Mutasem Omar Sinnokrot
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (565 download)

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Download or read book Theoretical Investigations of Pi-pi Interactions and Their Role in Molecular Recognition written by Mutasem Omar Sinnokrot and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Noncovalent interactions are of pivotal importance in many areas of chemistry, biology, and materials science, and the intermolecular interactions involving aromatic rings in particular, are fundamental to molecular organization and recognition processes. The work detailed in this thesis involves the application of state-of-the-art ab initio electronic structure theory methods to elucidate the nature of pi-pi interactions. The binding energies, and geometrical and orientational preferences of the simplest prototype of aromatic pi-pi interactions, the benzene dimer, are explored. We obtain the first converged values of the binding energies using highly accurate methods and large basis sets. Results from this study predict the T-shaped and parallel-displaced configurations of benzene dimer to be nearly isoenergetic. The role of substituents in tuning pi-pi interaction is investigated. By studying dimers of benzene with various monosubstituted benzenes (in the sandwich and two T-shaped configurations), we surprisingly find that all of the substituted sandwich dimers considered bind more strongly than benzene dimer. We also find that these interactions can be tuned by a modest degree of substitution. Energy decomposition analysis using symmetry-adapted perturbation theory (SAPT) reveals that models based solely on electrostatic effects will have difficulty in reliably predicting substituent effects in pi-pi interactions.