Reactive Scattering of OxygenAtoms With Bromine Molecules

Reactive scattering of O atoms with Br 2 molecules has been studied at an initialtranslational energy E~35 kJ mol −1 using cross-correlation time-of-flight analysis withresolution improved over previous measurements. The centre-of-mass differential crosssection peaks in the forward and backward directions with a higher product translationalenergy for backward Scattering. The angular distribution traced at the peak of theproduct velocity distribution peaks more sharply in the forward than the backwarddirection but the angular distribution of product flux shows a distribution which is morenearly symmetrical about θ = 90 ° . The observed scattering is attributed to a tripletOBrBr complex intermediate with a lifetime which is shorter than the period of overallrotation of the axis of the heavy BrBr diatomic but which is long compared with theperiod of vibrational and rotational motion of the light O atom.