The structurally similar T, C-1 and C-3 isomers of C60F36 show significant differences in electrochemical behaviour, the reduction potentials (vs. SCE) being 0.04, 0.07, and 0.12 V, respectively. The relative addend positions influence both the energetics of the first one-electron reduction of C60F36 and the stability of electrochemically generated C60F36.-. Thus whereas full reversibility of the first reduction is observed at scan rates as low as 0.5 V/s for C-3-C60F36, reversible peaks were obtained for T- and C-1-C60F36 only at scan rates greater than or equal to 50 V/s. The subsequent multi-electron reductions Of C60F36 occur at more negative potentials, and are accompanied by irreversible loss of fluorides, analogous to the behaviour of other perfluorinated fullerenes. (C) 2004 Elsevier B.V. All rights reserved.