Formation of fullerene clusters in carbon disulfide: Data on small-angle neutron scattering and molecular dynamics

Abstract

Fullerene solutions in carbon disulfide are studied by small-angle neutron scattering (SANS). In addition to earlier experiments on the given system, the range of measured transmitted impulses is extended and the influence of solution preparation methods on C60 cluster formation in these solutions is studied. It is shown that the formation of large C60 clusters (with a size of about 10 nm) is due to nonequilibrium methods of solution preparation. For nonequilibrium dissolution, there is a 10% excess of the observed fullerene size in the solution over the calculated value. It has been established by simulation of the C60/CS2 interface by molecular dymanics methods that inclusion of how solvent molecules are organized on the C60 surface leads to a decrease in the fullerene size in the solution, observed by using SANS. In this paper, the effect of excess Rg is explained by the presence of small clusters in the solution (approximately 10% of dissolved C60 molecules). It is discovered that there is a time variation in the concentration of the saturated solution. The explanation of this effect using a model of formation and sedimentation of large clusters (with a size of 100 nm or more) is proposed.