The ground-state rotational spectra of four isotopomers of the complex OC3. C1F have been observed by using a fast-mixing nozzle in a pulsed-nozzle, Fourier-transform microwave spectrometer. The spectrum of the reaction product carbonyl chloride fluoride was detected by its intensity indicated that the extent of the reaction was small. The observed spectroscopic constants B0, DJ, χaa (Cl) and Mbb (Cl) were interpreted to show that the ...