Cluster-cluster fusion

An experimental study of molecular fusion in fullerene-fullerene collisions is presented and the theoretical interpretation of the cross section is reconsidered in terms of phase space arguments and competition with direct collision induced dissociation. The form and absolute magnitude of the cross sections for C60+ + C-70 (or C-70(+) + C-60) and C-70(+) + C-70 can be understood, however, the much smaller cross section for C-60(+)+ C-60 remains a puzzle. The fragmentation behaviour of the hot fusion product is well described by a maximal entropy model indicating equipartition of the centre of mass collision energy followed by statistical fragmentation. (C) 2002 Academie des sciences/Editions scientifiques et medicales Elsevier SAS.