Molecular structure and energetics of sym-ClO3

The equilibrium structure, vibrational spectra and heat of formation for sym-ClO3 have been investigated using high levels of ab initio theory. Methods include second-order Møller-Plesset perturbation theory (MP2) and singles and doubles coupled-cluster theory which incorporates a perturbational estimate of effects of connected triples excitation [CCSD(T)]. Two density functional methods were also investigated. At the highest level of theory, CCSD(T)/6-311 + G(3df)//CCSD(T)/6-311G(2df), the heat of formation for sym-ClO3 is predicted to be 46.0 ± 3 kcal mol−1 at 0 K.