Solid state NMR studies of covalent graphite fluorides (CF)n and (C2F)n

Various covalent graphite fluorides were studied using solid state nuclear magnetic resonance (NMR). 19F magic angle spinning (MAS) NMR, 13C MAS NMR and 13C MAS NMR with 19F to 13C Cross Polarization (CP) allow both the presence of CF and CF2 groups and the carbon atoms hybridization, sp2 or sp3, to be determined. 19F spin–lattice relaxation time T1 of the 19F line is presented. The effects of paramagnetic centers on the relaxation were evaluated. Paramagnetic oxygen is shown to be an important source of relaxation. The presence of a molecular motion with an activation energy of 1.685 kJ mol−1 is also evidenced for one of the (CF)n sample.