DFT calculation and matrix isolation FTIR studies on the formation of CF3OBr from

The 266 nm laser photolysis of argon matrices containing dilute O3 and CF3Br gives rise to three main infrared (IR) bands at 1249.4, 1204.2 and 1201.9 cm−1. The primary possible intermediates CF3BrO and CF3OBr, which might generate from reactions between mobile O(1D) atoms and isolated CF3Br, are characterized by DFT calculations for the first time. Geometries, energies, vibrational frequencies and the IR intensities of these two intermediates are obtained. Theoretical studies support the assignments of the observed IR bands to C–F stretching modes of the hyperbromite compound CF3OBr. Mechanism is proposed as reaction between O(1D) and CF3Br to generate excited CF3BrO initially, which readily undergoes fragmentation to CF3 and BrO due to the weak bonding of C–Br in CF3BrO, and fast recombination of CF3 and BrO in the matrix cage produces the final product CF3OBr.