Resonance energy transfer from solid to adsorbed molecules under radiolysis of the N2O–MgO system

Abstract

The radiolysis mechanism of nitrous oxide adsorbed on magnesia has been studied at 77 K using e.s.r. spectroscopy and chromatography. The radiative decomposition of nitrous oxide is shown to take place not only during the dissociative capture of electrons, but also during the interaction of its molecules with magnesia exitons. At a monolayer coverage θ < 0.75 the interaction of nitrous oxide with exitons of a solid involves both an ionic and a molecular mechanism, whereas at a monolayer coverage only a molecular mechanism is observed. In this case five magnesia exitons cause decomposition of seven nitrous oxide molecules. The transition from an ionic interaction between N₂O molecules and exitons to a molecular one as a result of raising the irradiation temperature of nitrous oxide adsorbed on magnesia (θ= 0.5) has been revealed.