Calcul semi empirique des energies empiriques. Mise en evidence d'interactions entre groupes non lies

Abstract

The energies of bicyclo[2.2.1]heptane alcohols and ketols have been calculated by the PCILO method in the CNDO approximation. These calculated energies are consistent with additive empirical laws for bond energies and interaction energies. Interactions between non bonded atoms and groups are calculated by comparison between homologous molecules differing by one substituant. Examples are given for repulsion between hydroxyl and methyl hydrogens, and attraction between hydroxyl hydrogen and carbonyl oxygen. The interaction between two hydroxyl groups is discussed on the basis of hydrogen bonding, dipolar interaction and Van der Waals repulsion.