K. Sankaran et al., Matrix isolation infrared studies of the reactions of laser-ablated uranium with N-2: Reactions beyond insertion into N-2, J PHYS CH A, 105(16), 2001, pp. 3995-4001
Uranium was laser-ablated in the presence of N-2/Ar mixtures, and the react
ion products were studied using matrix isolation infrared spectroscopy. The
se reactions were studied over a wide range of N-2 concentrations in Ar (0.
1% to 50%) and also with pure N-2. We observed that at low N-2 concentratio
ns in Ar (<1%), the reaction product was the insertion product UN2 and its
complexes with molecular N-2, a result that agreed xwith an earlier report
of Andrews and group. Interestingly, however, as the N-2 concentration was
increased, we observed the formation of the mononitride, UN. We believe tha
t as the N-2 concentration is increased, new reaction channels open up, res
ulting in the formation of nitrogen atoms and N-3 species which then react
with laser-ablated uranium atoms to produce UN. The assignment of the infra
red feature due to UN in a N-2 matrix is also discussed.