NMR study of solid C-60 (gamma-cyclodextrin)(2)

A solid complex of C-60 with gamma-cyclodextrin (gamma-CyD) was examined with NMR spectroscopic methods in order to understand the dynamics of C-60, and the interaction between C-60 and gamma-CyD. A C-13 solid-state cross-polarization magic angle spinning (CP/MAS) NMR spectra shows C-60 resonance at 142.6 ppm. This provides the evidence of interaction between C-13 spins in C-60 and H-1 spins in the gamma-CyD host. Ambient temperature experiments on the C-13 CP/MAS NMR, with varying contact time, shows that the water associated with gamma-CyDs plays an important role in the nuclear relaxation processes. The dynamics of C-60 in gamma-CyD was investigated using temperature and field-dependent C-13 spin-lattice relaxation time measurements. The influence of water on the dynamics of C-60 was less significant below 250 K. (C) 1997 Elsevier Science B.V.