Knowledge Bank

Two band systems of the FeF radical have been recorded at Doppler-limited linewidths by Laser Induced Fluorescence. The (0,0) band of the $\mathrm{<mrow\; data-mjx-texclass="ORD">6</mrow>}\Pi -X6\Delta$ was recorded at 323 nm. The system at 330 nm consisted of and overlap of the (1,0) band of the $\mathrm{<mrow\; data-mjx-texclass="ORD">6</mrow>}\Pi -X6\Delta$ system and the (0,0) band of the $\mathrm{<mrow\; data-mjx-texclass="ORD">6</mrow>}\Phi -X6\Delta$ system. FeF was producedd in a continuous flow by the reaction of fluorine atoms, produced by a microwave discharge of fluorine in helium, with iron pentacarbonyl. This reaction provides date for the lowest four sub-bands of each system, considerably extending our knowledge of these two electronic transitions compared with previous work by $Pouillyetal.a$ The temperature of the temperature of the sample in our experiments is slightly above ambient, about 450 K, The results have been analysed and combined with the millimeter-wave $spectrab$ for the ground state, $\mathrm{<mrow\; data-mjx-texclass="ORD">6</mrow>}\Delta$, to produce better parameters for the excited states.