H-1-F-19-C-13 double cross polarization (DCP)/magic angle spinning (MA
S) C-13 n.m.r. and C-13-F-19 rotational echo double resonance (REDOR)
CP/MAS C-13 n.m.r. experiments performed on two low-molecular-weight m
onofluorinated organic compounds are reported. DCP n.m.r. permits the
selective identification of resonances of carbons one- and two-bonds r
emoved from a fluorine atom in these substances. Under our experimenta
l conditions the F-19 T2 is on the order of 1 ms or less. This relaxat
ion process is beneficial in the DCP experiment. It defeats proper ech
o formation in C-13-F-19 REDOR CP/MAS C-13 n.m.r. experiments in which
MAS speed and F-19(T2)-1 are comparable. Potential remains for REDOR
in coal structure analysis under experimental conditions that result i
n lengthened F-19 T2.