Reactive Scattering of Oxygen Atoms With Bromine Molecules

Reactive scattering of O atoms with Br₂ molecules has been studied at an initial translational energy E~35 kJ mol⁻¹ using cross-correlation time-of-flight analysis with resolution improved over previous measurements. The centre-of-mass differential cross section peaks in the forward and backward directions with a higher product translational energy for backward Scattering. The angular distribution traced at the peak of the product velocity distribution peaks more sharply in the forward than the backward direction but the angular distribution of product flux shows a distribution which is more nearly symmetrical about θ = 90^°. The observed scattering is attributed to a triplet OBrBr complex intermediate with a lifetime which is shorter than the period of overall rotation of the axis of the heavy BrBr diatomic but which is long compared with the period of vibrational and rotational motion of the light O atom.