Large-scale ab initio calculations have been performed on the complexes NH3·HCl, NH3·HBr, CH3NH2·HCl and CH3NH2·HBr. Two-dimensional energy surfaces as a function of RN---X and RHX have been scanned in order to explore the possibility for the formation of stable vapor-phase ion-pair complexes. While the complexes NH3·HCl, NH3·HBr and CH3NH2·HCl are still of the neutral type, the ionic form CH3NH3+·Br+ is energetically slightly more favourable than the neutral-type complex. Further increase in base strength of the amine will result in stable ionic amine HX complexes in the vapor phase.
|Number of pages||7|
|State||Published - Oct 1 1984|