NMR techniques have been used in graphite intercalation systems for chemical analysis and for determinations of structure, molecular dynamics, exchange kinetics, conductivity and electron concentration. Salient results will be presented. We have been most interested in understanding the reaction
3AsF5 + 2Cn ⇋ 2CnAsF6 + AsF3 (1)
for which a single, extremely narrow 19F NMR line is observed when AsF5 reacts with graphite. In contrast, when the reaction
NO2AsF6(in CH3NO2) + Cn→NO2 ↑ + CnAsF6 (2)
is carried out, followed by addition of the stoichicmetric amount of AsF3, separate spectra for the AsF6 (a broad doublet) and lor AsF3 (a sharp 1:2:1 triplet) are observed, indicating that these two species do not exchange fluorine atoms, and suggesting that eq. (1) is not reversible. The AsF3 triplet gives an order parameter for the molecular thrae fold axis with respect to the graphite c-axis. The carbon-13 spectrum for a fifth stage intercalate of HNO3 shows the 2:2:1 triplet expected if each kind of layer Is resolved.