Structure and stability of two-dimensional systems of C20 fullerenes

Abstract

Two-dimensional systems of C20 fullerenes connected to each other by strong covalent bonds have been investigated. Several isomers differing in the type of intercluster bonds have been revealed. The lifetimes τ of the (C20) M × M complexes with M = 2 and 3 at T = 1800–3300 K have been directly calculated using the molecular dynamics method. It has been shown that these complexes lose their periodic cluster structure due usually to the coalescence of two or several neighboring C20 fullerenes. The activation energy of this process determined by analyzing the τ(T) dependence appears to be E a ≈ 2.5 eV in agreement with the calculations of the heights of the potential barriers preventing the coalescence. At high temperatures T > 2400 K, the decay of C20 fullerenes entering into the complex is possible.