science-softCon uv/vis+ photochemistry database; www.photochemistry.org; (C) science-softCon 2019 Substance: ozone Other Names: Formula: O3 CAS-No.: 10028-15-6 Study: photolysis, quantum yields Authors: C. Cobos, E. Castellano, H.J. Schumacher Title: The kinetics and the mechanism of ozone photolysis at 253.7 nm Journal/Source: J. Photochem., 21 (4), 291-312, (1983); doi:10.1016/0047-2670(83)87116-0 Data: Energy/Wavelength range: 253.7 nm Resolution: Temperature: 298 K Temperature dependence: no Pressure/Concentration: 1 - 2 Torr and 50 Torr (ozone) Phase: gas pH: Comments: The photolysis of ozone by steady illumination at 253.7 nm and 25 °C was studied. The experiments were performed in pure ozone and in ozone containing oxygen, helium, sulphur hexafluoride and nitrogen. The quantum yield Phi of the decomposition of pure ozone was 5.68 ± 0.15 molecules quantum-1 and was pressure independent. The quantum yields Phi(He) and Phi(SF6) of the decomposition of ozone in He-O3 (pHe/pO3 ~ 600) and SF6-O3 (pSF6/pO3 ~ 300) were 5.62 ± 0.41 molecules quantum-1 and 5.44 ± 0.32 molecules quantum-1 respectively. In N2-O3 mixtures with high values of pN2/pO3 the quantum yield decreases to 4 molecules quantum-1. The quantum yield Phi for O(1D) production is 0.92 ± 0.04 atoms quantum-1. Author to whom correspondence should be addressed: (e-mail address):