Concerning the origin of 19F-19F NMR COSY and NOESY connections in the spectra of perfluorooctanoic acid, R(F)-palmitic acid-F13 and diethyl perfluorosuberate.

A combination of 19F nuclear Overhauser effects (NOE) and molecular mechanics calculations are presented for delineating the spatial origin of the well-known four-bond 19F-19F COSY connections which are generally observed in the 19F NMR spectra of compounds containing perfluorinated chains. Perfluorooctanoic acid (PFOA), R(F)-palmitic acid-F13 and diethyl perfluorosuberate were used as test cases. Spin-lattice relaxation times (T1) are included and NOESY correlations through three and four bonds occur.