Low reactivity of dry electron with matrix isolated N2O, observed by pulse radiolysis of solid crystalline hydrate

Conditions for the observation of dry electron reactions are outlined. A new system for the investigation of dry electron reactions is proposed. It is the aqueous clathrate of tetrabutylammonium hydroxide or fluoride in which N2O also is matrix isolated, with negligible interaction with water molecules. The system, both liquid and solid may be investigated at room temperature. In the former, the hydrated electron disappears very rapidly as usual, but in the crystalline version the electron trapped in crystalline defects survives by three orders of magnitude longer. That is the result of competition for thermalised electrons between N2O and the trap, which act more efficiently. As the concentration of N2O is similar to the concentration of electron traps, one can estimate the cross-section of the reaction with N20 to be by four orders of magnitude lower than for the reaction of trapping of electron. The situation is reversed in comparison to liquid aqueous solutions, where the reaction of hydrated electrons with N2O belongs to the fastest reactions known, occurring with every collision. Possible consequences of low reactivity of dry electrons with N2O in non-aqueous systems are discussed. (author)