ON THE BONDING AND STRUCTURE OF ETHYLENE-BRCL ADDUCTS

Geometric structures, limited sections of the potential surface and di pole moments of the ethylene-BrCl complex have been computed using the MP2 method and a double zeta + polarization basis set. The theoretica l results confirm the experimental observation of a pi adduct of neutr al monomers. The complex is bound by 0.23 eV with respect to dissociat ion to ethylene + BrCl and 5.75 eV with respect to dissociation to eth ylene-Br+ + Cl-. The evolution of the outer, pi complex of neutral eth ylene and BrCl into the inner, ionic one is rationalized in terms of i nteractions of the covalent and ionic potential surfaces.