Infrared diode laser spectroscopy of the CF radical

The fundamental bands of the CF radical in the X ²Π_{1}/{2} and X ²Π_{3}/{2} electronic states were observed by using an infrared tunable diode laser as a source. Zeeman modulation could be used in detecting lines not only in the ²Π_{3}/{2} state, but also in ²Π_{1}/{2}, because the CF radical deviates considerably from Hund's case ( a). From the least-squares analysis of the observed spectra, the following molecular constants were obtained: B_e = 1.416 704 (37) cm ^-1, α_e = 0.018 419 (50) cm ^-1, r _e = 1.271 977 (17) Å, D_e = 6.68 (15) × 10 ^-6cm ^-1, p₀ = 0.008 580 (21) cm ^-1, p₁ = 0.008 52 (11) cm ^-1, and overlineν₀ = 1286.1281 (5) cm^-1, with three standard errors in parentheses.