(Unfortunately, this experiment cannot be run on the 500 cryoprobe)

Comparing 19F spectra with and without 1H decoupling can probe the interaction between 19F and neighboring 1H.

Here is a comparison. Sample: (CF3)2COOH in 90/10 H2O/D2O. Note that the 19F-1H J coupling is ca. 8 Hz even though they are four bonds away. (run on the old DPX300. Now gone)