Flash Photolytic Production, Reactive Lifetime, and Collisional Quenching of O2(b 1Σg+, υ′ = 0)

Kinetics and Products of the Reaction O2(1Σg +) with N2O

Previous studies have suggested that the reaction of O2(1Σg +) + N2O → NO + NO2 may be a significant source of NOx in the atmosphere if the branching ratio of this channel is greater than ~1%. We have measured the overall rate coefficient (k1) for the reaction of O2(1Σg +) with N2O to be k1(295 K) = (1.06±0.14)×10−13 cm3 molecule−1 s−1 at 295 K and k1(T) = (7.48±1.66)×10−14 exp[(87±40)/T] cm3 molecule−1 s−1 as a function of temperature over the range 210–370 K. The yields of NO, NO2 or O3 that are possible reaction products from the title reaction were undetectably small. Also, the net loss of N2O from the title reaction was negligibly small. We report upper limits for the yields for the production of NOx, the production of O3 and the loss of N2O (all at 298 K) to be < 2×10−4, < 1×10−3, and < 3×10−3, respectively. We conclude that the reaction of O2(1Σg +) + N2O is neither a significant source of NOx in the atmosphere nor a significant sink for N2O.

Possible high energy laser at 1.27 microm

Preliminary theoretical and experimental evidence is presented that suggests the potential of lasing from the strongly forbidden O(2)((1)Delta(g)) ? C(2)((3)Sigma (-)(g)) transition of molecular oxygen. A rate equation model is developed which predicts pulse energies up to several hundred joules/liter atmosphere for typical mixtures of 10(3):2N(2) activated by uv photolysis in less than 10 microsec. Preliminary results from a flash photolysis laser apparatus demonstrating 1.27-microm lasing are presented. Results from a computer analysis assessing the possibility of using this system as a multipass amplifier are also given.