Topic Insight

Teflon and fluorocarbon studies; 19F, 19F-13C and 1H-13C ssNMR analysis

Much like proton, fluorine is present in a wide variety of organic chemicals, biomolecules, polymers, APIs as well as other functional materials and it can exist in a range of environments that are often involved in key structural or functional motifs. The 19F nucleus (spin quantum number I = 1/2) possesses a very high magnetic moment (81% of1H) and 100% natural abundance, leading to exquisite NMR sensitivity and strong dipolar couplings. Furthermore, owing to the lone pairs of electrons on a 19F substituent, its isotropic chemical shift has a much broader range than 1H (∼800 ppm, compared with the ∼25 ppm typically found for 1H), and are particularly sensitive to the small changes in local environment. Therefore, 19F become a favorable nucleus for ssNMR spectroscopic analysis involving multinuclear multidimensional correlation experiments.