The collisional stabilization of excited β-naphthylamine molecules by the paraffin hydrocarbons in the gas phase

Abstract

The transfer of vibrational energy from molecules of β-naphthylamine excited by the mercury lines at 2804 A and 2652 A to the homologous series of paraffin hydrocarbons up to n-hexane has been investigated in the gas phase at 180°C. Although the average amount of energy transferred collisionally increases with the complexity of the added gas by a factor of 5, the transfer efficiency expressed as an accommodation coefficient remains virtually unchanged. A transfer mechanism based on the internal redistribution of vibrational energy within the collision complex is examined, in terms of which it is unnecessary to invoke vibration-vibration transfer except for pentane and hexane. The collision duration estimated on the basis of this model is well within an order of magnitude of that expected from collision diameters and relative velocities of the molecules concerned.