Structures of Binary C₆₀−C₈₄Fullerene Clusters

Abstract

A systematic study of the potential energy global minimum (GM) structures of model binary fullerene clusters of compositions (C(60))(n)(C(84))(N-n), N </= 24 has been carried out using the basin-hopping method. The stiff Girifalco pair potential is used. We report a novel GM geometry for (C(84))(13) with D(5) geometry. To the best of our knowledge, this is the first reported homogeneous 13-particle cluster whose potential is pairwise additive that has this structure. For homogeneous fullerene clusters larger than N = 13, the dominant packing motif is decahedral. By contrast, for the binary clusters studied, polyicosahedral structures are observed for a broad range of cluster sizes and compositions. It is pointed out how the favorable size ratio reduces strain to produce these packing motifs. For N = 23 and N = 24, we observe a reduced strain "stacked" polyicosahedral motif between the compact polyicosahedral and decahedral stability regions. Mackay-icosahedron based GMs were found for clusters (C(60))(1) (C(84))(N-1), N > 18.

Impact of different potentials on the structures and energies of clusters

“…In practical works, potential functions are selected to find a balance between accuracy and calculation consumption. Different potentials, however, generally lead to different results for a cluster, as have been discussed in literatures 6–12…”

On the use of big‐bang method to generate low‐energy structures of atomic clusters modeled with pair potentials of different ranges

“…[40] In turn, the big‐bang method is not expected to reach easily the global minimum of systems modeled with short‐ranged potentials (also designated as stiff potentials), e.g., in fullerene‐like aggregates such as $({\rm C}_{60})_n$ , $({\rm C}_{84})_n$ , and the binary $({\rm C}_{60})_n ({\rm C}_{84})_m$ (see Ref. [67] and references therein) or in colloidal clusters whose corresponding Morse ρ parameter was estimated to be 25 or even higher (see Refs. [68, 69] and references therein).…”