Solid C-60 was stored in NO or O-2 under high pressure, and subsequently the molecules of either gas were found to have diffused into the octahedral interstitial sites in its fcc lattice. C-13 NMR MAS spectroscopy revealed a primary resonance at 143.7 ppm, accompanied by several minor peaks shifted downfield. Measurement at temperatures from 210 to 300 K indicated a linear dependence of the chemical shifts of these minor peaks on inverse temperature,with intercepts equal to integral multiples of 0.13 ppm. In view of these finite intercepts at the high-temperature limit, we propose that there are charge transfers to C-60 from NO and from O-2. The quantities of the charge transferred have been calculated, and in both cases are about 0.065 electron charge. (c) 2005 Elsevier B.V. All rights reserved.