A computational study of the ozone dimer

The dimer of ozone is treated ab initio by the second-order Møller-Plesset perturbation approach with the 6-31G* and 6-1+G* basis sets (with an evaluation of the basis set superposition error and the fourth-order corrections). It is found that the minimum-energy structure exhibits C_s symmetry (with some patterns resembling the structure of the water dimer). The calculated dimerization energy varies between -13 and -1 kJ/mol. Monomer-dimer shifts in the vibrational frequencies are rather small (about 10 cm^-1 or less) while the inter-molecular frequencies vary between 30 and 120 cm^-1. The ozone dimer could influence some spectral observations under atmospheric conditions.