Thermal Electron Attachment to Nitrous Oxide

Thermal electron attachment to nitrous oxide was investigated in the range −66 to 215°C. The attachment was found to be dissociative in nature with an activation energy of 10.4±0.4 kcal/mole. The activation energy is thought to arise from electron attachment to molecules thermally excited primarily in the bending mode. In an attempt to explain the activation energy a simple Morse function was employed. Potential energy as a function of internuclear distance for both N2O and N2O− was generated at different N2O bond angles. In this manner a three-dimensional surface for the reaction, N2O (linear)→N2O (bent)→ lim +e−N2+O−, was obtained. The potential surface has a minimum at a bond angle ∼160°. The electron affinity of N2O is estimated at 6.2±4 kcal from the calculated N2O− potential-energy surface. This is in general agreement with other reported values.