A coupled-cluster study of the HOBr→HBrO transition state

The structural and energetic properties of the HOBr→HBrO transition state are examined using the single and doubles coupled-cluster method that includes a perturbational estimate of the effect of connected triple excitations [CCSD(T)]. The energy change for the isomerization reaction is best estimated to be 56.5 kcal mol−1 endothermic, and the activation energy for the process is 75.0 kcal mol−1.