Book Description

Two aspects of molecular decomposition on MgO(100) surfaces were explored. Nitrogen dioxide entrained in a molecular beam was photoexcited and directed at a crystal surface. Following collision, it had enough internal plus translational energy to undergo dissociation. The NO products, which were detected with state and angular resolution, were scattered preferentially in the specular direction and their internal energies were analyzed The results showed that the collisional dissociation was rather efficient when the molecules possessed internal energies approaching dissociation energy The photochemistry of CINO was examined on MgO and compared with the analogous gaseous phase photodissociation; a large, qualitative difference was observed. Defect-laden and relatively defect-free MgO(100) surfaces were used. Gas phase 355 nm photolysis yielded NO with a rotational distribution peaked at high rotational levels, whereas adsorbed CINO always yielded cold NO. The results suggested that CINO aggregated on the surface in a way that affects photon-induced processes. The gas-phase photodissociation dynamics of FNO and methyl nitrite were examined as candidates for comparisons with surface photolysis. jg p1.