Kinetics of CO Formation Studied by Far-uv Flash Photolysis of CO2

Abstract

A simple, low-energy (100–200 J), short-duration (3-μsec) flash-photolysis apparatus for the vacuum ultraviolet down to the transparency limit of lithium fluoride (1100 Å) is described. The photolysis of CO2 has been studied. Recombination rate of CO+O(1D) is 2×109 liters mole−1·sec−1 in the presence of a large excess of nonphotolyzed CO2 which may act as a third body. From kinetic considerations, the average lifetime of O(1D) was estimated to be of the order of 50 μsec under these experimental conditions. The fact that O(1D) plays a role is supported by the observation at 1152±0.5 Å of an absorption which could be attributed to the (2p41D−3s11D°) transition known in emission.