Rotational transitions 101→000, 2 12→111, 211→212, and 321→322 of 1,1 difluoroethylene were studied using a molecular beam maser spectrometer. Emission transitions were observed with 6 kHz linewidth (FWHM) and hyperfine structure due to fluorine and hydrogen interactions was resolved. The diagonal elements of the fluorine spin-rotation tensor are Maa=-13.4±3.6 kHz, Mbb=-10.94±0. 68 kHz and Mcc=-6.06 ±0.68 kHz. This data is used to determine paramagnetic contributions to the fluorine chemical shift tensor. Analysis of the data yielded line centers for the rotational transitions of 15774348 ±3 kHz for 101→-000, 26465055±5 for 212→111, and 14419906±3 kHz for 3 21→322, and 15250615±3 kHz for 2 11→212. Results of semiempirical calculations of diamagnetic contributions to the shielding tenors are presented for CH 2CF2 and other molecules. Comparisons of total shielding tensors are made for related molecules.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry