Infrared spectrum of elusive C2F radical: A matrix-isolation and computational study

We study theoretically and experimentally the infrared absorption spectrum of C2F radical. The calculated spectrum of C2F shows characteristic bands at ca. 1600 cm−1 and rich absorption patterns above 4500 cm−1 with very high intensities (up to ∼104 km mol−1). In experiment, C2F radicals were obtained by ultraviolet photolysis of HCCF in Ar and Kr matrices at 9 K. The experimental evidence and good agreement with the theoretical results allow us to report for the first time the experimental spectrum of C2F radical. In agreement with theory, the C2F absorption bands are very strong in the experimental spectra compared to the bands of C2H and HCCF.