Charge exchange and cluster formation in an rf Paul trap: interaction of alkali atoms with C +60

Abstract

A Paul ion trap was used to study the formation of clusters under controlled temperature and pressure conditions. Exposure of cold C + 60 ions to Li flux leads to the formation of Li n C + 60 clusters ( n = 1–18) occurring by the sequential association of Li atoms. Cluster formation dependence on He pressure displayed a competition between vibrational relaxation and unimolecular dissociation. Collisions with Na, K, Rb and Cs atoms resulted in dissociative charge exchange. Decay rates of C + 60 ions resulting from these low-energy charge exchange collisions were consistent with Langevin capture rates.