Molecular Electrostatics for Exploring Complexes of Carbonyl Compounds and Hydrogen Fluoride

Abstract

The negative-valued molecular electrostatic potential (MESP) minima (Vmin) observed in the substituted carbonyl molecules are found to be a sensitive measure for the analysis of the electronic charge perturbations due to the substituents. MESP topography of eight monosubstituted aliphatic carbonyl molecules (HCOR: R = H, F, Cl, CN, OH, SH, NH2, CH3, CF3, NO2) [following Bobadova-Parvanova, P.; Galabov, B. J. Phys. Chem. A 1998, 102, 1815] is carried out at the HF-SCF/6-31G** level for assessing this scheme. The Vmin values are seen to clearly reflect the changes due to the electron donating/withdrawing substituents. The electrostatic potential for intermolecular complexation (EPIC) model is used for predicting the possible hydrogen-bonded structures of the carbonyl molecules with the hydrogen fluoride. These complexes are further optimized at the HF-SCF/6-31G** level of theory. An excellent linear correlation is obtained with EPIC energy and the corresponding optimized interaction energy of the complex. ...