Absolute chlorine atom quantum yield measurements in the UV and VUV gas-phase laser photolysis of CCl4
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چکیده
Absolute quantum yields) Cl+Cl* for the formation of chlorine atoms were measured under collision-free conditions for the gas-phase dissociation of carbon tetrachloride (CCl 4) after pulsed laser photoexcitation at 193 and 135 nm. By means of a photolytic calibration method, where the gas-phase photolysis of HCl was utilized as a reference, values of) Cl+Cl* (193 nm) = 1.5 ± 0.1 and) Cl+Cl* (135 nm) = 1.9 ± 0.1 could be obtained which demonstrate the importance of the ultraviolet (UV) and vacuum-UV photolysis of CCl 4 as an efficient source of atomic chlorine formation.
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