Reaction of O(3P) atoms with benzene

The gas-phase reaction of O(P-3) atoms with benzene was investigated in a flow system in the pressure range of 50-100mbar and a temperature of 295 +/- 2K with a focus on the product formation. O-2 concentrations in the carrier gas were in the range of (7.7-84) x 10(14) molecule cm(-3). The primary stable products detected were phenol, benzene oxide/oxepin and a not identified compound with the probable composition C5H6O. The yields of phenol and benzene oxide/oxepin were 0.12 +/- 0.02 and 0.26 +/- 0.06, respectively, being not affected by the experimental conditions. For benzene oxide/oxepin, a rapid consecutive reaction with O(P-3) atoms was observed with a rate coefficient of k((295 K)) = (1.1 +/- 0.1) x 10(-10) cm(3) molecule(-1) s(-1) measured at a pressure of 100 mbar. A substance with the formula C6H6O2 (likely oxepin 4,5-epoxide or oxepin 2,3-epoxide), the isomers of muconaldehyde, as well as formic acid, acrolein and trans-butenedial were identified as products of the reaction of O(P-3) atoms with benzene oxide/oxepin.