A reinvestigation of the hyperfine structure in fluoroform

The hyperfine structure of the J = 1 - 0 rotational transition of the CF₃H and CF₃D molecules has been reinvestigated with a high resolution beam maser spectrometer equipped with a nozzle source. Considerable gain in S/N ratio compared with previous measurements performed with a normal effuser source is obtained. The experimental result eliminate discrepancies between the results of previous investigations.