O1D quantum yields from O3 photolysis in the near UV region between 305 and 375 nm

This is the authors' abstract. We don't add key points for this paper.

The formation of O 1D from the photolysis of ozone has been observed at photolysis wavelengths between 305 and 375 nm and relative quantum yields for O 1D production have been determined. Ozone was photolyzed using a frequency doubled, optical parametric oscillator. O 1D was monitored indirectly, using laser induced fluorescence (LIF) detection of vibrationally excited OH as a ‘‘spectroscopic marker’’. Relative O 1D yields were measured from 305 to 375 nm at 295 K and from 305 to 340 nm at 273 K. The quantum yield decreases between 305 and 325 nm with a temperature dependence in the range between 310 and 325 nm. This is consistent with O 1D production via both spin-allowed and spin-forbidden processes. Between 325 and 375 nm a constant quantum yield of 0.064±0.006 was obtained suggesting production via an exclusively spin-forbidden process and indicating that absorption takes place to a single excited state which either predissociates, yielding O3P and O23Σ−, or crosses to another surface before dissociating to produce O 1D and O23Σ−.