F-19 SPIN ROTATION AND SPIN SPIN INTERACTIONS OF SILICON DIFLUORIDE AND GERMANIUM DIFLUORIDE PREPARED IN AN ELECTRIC-DISCHARGE, OBSERVED WITH A CAVITY MICROWAVE FOURIER-TRANSFORM SPECTROMETER

Rotational transitions of 28SiF2 and four isotopomers of GeF2 have been investigated using a cavity pulsed microwave Fourier transform spectrometer. Both molecules were prepared in electric discharges, in SiF4 and GeF4, respectively. The high resolution of the spectrometer has permitted the first measurements to be made of the 19F hyperfine structure, which has been analyzed in terms of spin-spin and spin-rotation coupling constants. For both molecules the spin-spin coupling constants have been used to evaluate the F-F internuclear distances: good values have been obtained which are in agreement with, but slightly smaller than, the re values. © 1993 Academic Press, Inc.