Nitrous oxide, N2O, was observed to react with F-2 under UV irradiation at -196 degrees C to form initially F2N2O which in accord with earlier reports from the literature decomposes above -140 degrees C to form N2F4 and NO. The apparently different reaction behavior of N2O toward H radicals (-->H2O + N-2) and F radicals (-->F2N2O --> N2F4 + NO) can be accounted for by thermodynamic considerations [average bond energies (kcal mol(-1)): O-H (114.2) > N-H (93.3); N-F (66.4) > O-F (44.7)]. A reaction mechanism for the formation and decomposition of F2N2O from N2O and F-2 (present study) and from N2F4 and NO has been suggested using valence bond considerations. The structure of F2N2O was fully optimized at the electron correlated MP2(FULL)/cc-pVTZ level of theory and was shown to possess C-1 symmetry. A frequency analysis clearly shows the C-1 structure to represent a true minimum (NIMAG = 0), whereas the earlier reported planar C-s structure was shown to represent a first-order transition state (NIMAG = 1).