Photochemistry of CCl3F and CCl2F2 in the 106–200 nm region

Publisher Website
Google Scholar
Abstract
The photoabsorption cross sections and fluorescence excitation spectra of CCl3 F and CCl2 F2 were measured using synchrotron radiation at 106–200 nm. The observed absorption bands were accounted for as Rydberg transitions. The emitters produced from the CCl3 F and CC12F2 photodissociative excitations were attributed to CClF(Ã 1A‘←X̃1  A’) and CF2 (Ã 1B1 →X̃ 1A1 ) transitions, respectively, and their radiative lifetimes were determined to be 626 ± 28 and 58 ± 2 ns. The emission from the CClF(A) starts at 140 nm and increases to 9.1 Mb at 106 nm, and that for CF2 (A) was deduced to be 0.9 Mb at 104.8 nm. The onsets of the fluorescence suggest that the electronically excited CClF and CF2 radicals are formed by the atomic Cl elimination but not by molecular Cl2 releasing process.