Ab initio studies on complexes of ozone with triatomic and larger molecules.

Abstract

Abstract Using coupled cluster methods with quadruple-zeta basis sets stable structures were found for complexes of ozone with common triatomic molecules as well as with ammonia and methane. The largest dissociation energy of 917 cm− 1 was obtained for the hydrogen bonded O3-NH3 complex, exceeding the value for O3-H2O (787 cm− 1). The high dissociation energy of the O3-NH3 complex is seen as an exception to the expected sequence of stabilities. Large dissociation energies were obtained also for O3-SO2 (717 cm− 1), O3-N2O (688 cm− 1), O3-HCN (659 cm− 1) and O3-CO2 (652 cm− 1). Dissociation energies for the C1 structure (559 cm− 1) and Ci structure (556 cm− 1) of the ozone dimer are nearly identical despite pronounced differences in geometries. Hydrogen bonding of HF, H2O, NH3 and CH4 with ozone is contrasted to hydrogen bonding with the oxygen molecule. Large shifts in vibrational frequencies were found for the ozone dimer, with a red shift of 51 cm− 1 and a blue shift of 25 cm− 1 for the antisymmetric stretching band of ozone. Larger frequency shifts are also seen for complexes of ozone with NH3, HCN, H2O and N2O.