PROTON AND LI+ CATION INTERACTIONS WITH H2O3 AND H2O O-2 - AB-INITIO MOLECULAR-ORBITAL STUDY/

Ab initio molecular orbital calculations at the QCISD(FULL)/DZ+P level of theory were carried out on the hydrogen trioxides H2O3 and H2O/O-2 (O-2 is (3) Sigma(g)(-)) and their Li+ ion and proton adducts to dete rmine the binding energies (Li+ affinity-and proton affinity) for H2O3 -Li+ and H2O-Li+-O-2. Calculations include the thermochemistry at 298K and enthalpy corrections for comparison with experimental values. Our prediction for the binding energy of Li+ to H2O3 is 33.0 kcal/mol, wh ich closely resembles that between Li+ and homologous molecules of wat er and H2O2. In the case of the H2O-Li+-O-2 system, the process may be that a primary product of H2OLi+ would then bind to oxygen (or O2Lito water). Binding energies of H2OLi+ or Li+ to O-2 are 8.6 or 5.2 kca l/mol, respectively, which are smaller than those required for adduct formation under conventional experimental conditions. The overall resu lts suggest the validity of our recent experimental detections of Liion attachment to hydrogen trioxide. But the detection of the H2O-Li+- O-2 complex may not be possible.