Chlorine and bromine oxides: synthesis, structure, role in heterogeneous processes of stratospheric ozone decomposition

摘要

Heterogeneous chemical reaction of ozone with HBr and HCl adsorbed on the ice surface have been investigated under the temperatures 77 - 223 K. The processes occurs immediately with formation of dark brown, gold-yellow and yellow -orange coloured condensates in the case of HBr and red condensate with HC1. Accordingly to low temperature IR-spectroscopy in the case of hydrogen chloride the most thermodynamically stable ClO_2 is the dominant product of the reaction. In the case of HBr Br_2O forms initially. Then it suffers further sequential oxidation to Br_2O_3, BrO_2 (Br_2O_4) and Br_2O_5. The optimization of the geometry of chlorine and bromine oxides mentioned above, has been performed using ab initio quantum mechanical calculations.