Knowledge Bank

It is believed that producing and trapping high concentrations of reactive species in solid molecular hydrogen will ultimately lead to the development of new high performance rocket fuels.\textbf{189}, 351-365 (1994).} We think the NH radical could be a viable candidate and try to produce it by photolyzing ammonia (NH$3$) at low temperature in solid parahydrogen. Upon 193.3 nm photolysis of NH$3$, we observe both NH$2$ and NH radical photoproducts. No significant changes in the NH radical concentration have been detected during a period of 3 hours at 1.8 K, even though the reaction NH + H$2$ \rightarrow NH$3$ is highly exothermic and can occur by quantum mechanical tunneling even at these low temperatures. In contrast, the NH$2$ radical is only observed in FTIR scans recorded during photolysis and rapidly decays once the 193.3 nm laser is turned off. We will discuss the possible fates of NH$2$ and how conditions can be optimized to produce high concentrations of NH radicals.