ORGN 189 |
| William C. Herndon, Department of Chemistry, Department of Chemistry, University of Texas at El Paso, El Paso, TX 79968 |
| Electronic energies and enthalpic properties of large aromatic hydrocarbons are of interest in chemistry, physics, and materials science. However, computational resource requirements for large molecular systems grow exponentially with size, and larger systems are often difficult to converge. The most successful enthalpy (heat of formation) schemes for organic compounds are empirical atom, bond, or group additivity methods, parameterized with experimental enthalpy data. These procedures are usually applied to sets of similar, structurally related compounds. Using this approach, this presentation will demonstrate how calculated ab initio electronic energies for small polycyclic benzenoid aromatic hydrocarbons (PAHs) can be used to predict the electronic energies of much larger PAHs. Then we show that it is possible to extend additivity methodology to accurately correlate electronic energies and thermodynamic data for the existing large variety of aromatic structural types with known experimental values of standard heats of formation (polyphenyls, polycyclic benzenoids, Buckyballs and bowls, nonbenzenoid aromatics, helicenes) . |
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Functional pi-Electronic Systems
8:00 PM-10:00 PM, Sunday, March 23, 2003 Convention Center -- Hall G, Poster
Division of Organic Chemistry |