Knowledge Bank

When O$2$ trapped in solid neon at 4.3 K in sites adjacent to an NO molecule is excited by 240 to 420 nm radiation, NO$3$ is stabilized. Photoexcitation of NO$3$ to its 663-nm state, which has $2$E symmetry, leads to the re-formation of weakly interacting (O$2$)(NO) pairs trapped in solid neon. In addition to infrared absorptions near the gas-phase band centers of NO and O$2$, the weakly bound complex shows several absorptions at lower frequencies. Experiments in which either the O$2$ or the NO moiety of the initial sample deposit is enriched in O-18 show O-isotopic randomization of the complex which results from photodestruction of the NO$3$ product.