C-60(+) defect centers: effect of rubidium intercalation into C-60 studied by EPR

The vanishing of C-60(+) EPR centers during the intercalation of polycrystalline C-60 With rubidium is described as a two-stage process with inter- and intragrain penetration of rubidium into the C-60 sample. This process leads to quenching of C-60(+) hole states through a recombination process. Two aspects of the results are discussed: 1. EPR assignment of the spectrum usually observed in pristine polycrystalline C-60 samples. 2, Similarity of the kinetics of alkali inter- and intragrain penetration into powdered C60 to the kinetics of oxygen penetration through C-60 film, accompanied by the generation of C-60(+) centers. (C) 2000 Elsevier Science Ltd. All rights reserved.