Generation of CF(X 2Π) by 248 nm multi-photon dissociation of CF2Br2 Absorption cross section of nascent CF2Br

✍ Scribed by J. Van Hoeymissen; W. Uten; J. Peeters

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 353 KB
• Volume: 226
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(94)00687-3

✦ Synopsis

The CF (X) radical was generated by 248 nm excimer laser (Tp ~ 20 ns) photodissociation of gas-phase CF2Br2. The production of CF as a function of the photodissociation laser fluence • was monitored by laser-induced fluorescence (A 2y.+,._X 2I-1 ( 1, .

. . . /lip 0) transition). The observed O dependence shows that CF is formed by a sequentml two-photon process: CF2Br2 -* CF2Br + Br, followed by CF2Br ~ (CF + FBr) or (CF2 + Br ). The absorption cross section of the nascent photodissociating CFeBr was derived, via a novel approach, from the lcr versus • behaviour: o= (4.4 + 0.6) × 10-n cm-2 at 248 nm. Combination with absorbances measured in a recent short-pulse experiment shows that 30% + 10% of the primary CF2Br dissociates spontaneously into CF2 + Br.