A molecular modeling of iodinated organic compounds.

Abstract Thermodynamic quantities of some iodinated compounds have been studied by means of ab initio and density functional theory calculations. Since there are some limitations for heavy elements in the fifth row of periodic table such as the iodine atom, a high level of ab initio theory is developed to calculate the energy of iodinated compounds. The standard enthalpies of formation for alkyl iodides and other iodinated organic compounds have been computed and compared with available experimental data. The impact of iodine atoms on the change of enthalpies for deprotonation of iodobenzenes has been studied and a mathematical model is proposed for the effect of iodine on the change of deprotonation. The acidity of diiodophenols as a model for thyroxin hormone has been successfully calculated. The barriers for nucleophilic reactions of substituted methyl iodides are investigated and the energy profiles are characterized by double-well potentials which correspond to pre-reaction and post-reaction complexes, separated by a transition state.