Coulombic model of the anomalous conformations of chlorinated acetates

CHED 1384

Taylor Arnold Barnes, tab3n@mtsu.edu and Preston J. MacDougall, pmacdougall@mtsu.edu. Department of Chemistry, Middle Tennessee State University, Murfreesboro, TN 37132
Quantum chemical calculations indicate that the chlorinated acetates favor several counterintuitive conformations in which a chlorine atom is eclipsed with a carboxyl oxygen. Calculations are presented for the chloroacetate ions, as well as their protonated forms and several of their ionic salts. The anomalous conformational energies are modeled in terms of a novel perspective on intramolecular Coulombic forces. The Coulombic force of attraction between complementary atomic dipoles, calculated utilizing the Quantum Theory of Atoms in Molecules (QTAIM), appears to dominate the energy of several conformations. This results in the intriguing conclusion that atoms of like charges may experience an attractive Coulombic interaction.