Fullerene-like clusters

Keywords carbon nanomaterials, exploding wires, spark erosion, fullerene-like clusters, ferromagnetic nanomaterials... 

TABLE 1. Spectral composition of the fullerene-like clusters produced by EW method in the case of explosion of different materials in the toluene at the next technological parameters - U=4.5 kV, E= 20 kJ, x =1 ms... 

Our results also address another relevant aspect of carbon clusters that is, the shape and the hybridization of the precursor aggregates. As we have shown, we are depositing particles in a mass range where fullerene-like shape and sp hybridization should be predominant [46,47]. However, an accurate analysis of the mass spectra shows that the contribution of odd clusters is not negligible (Figure 2.2). This suggests that non-fullerene type of clusters could be more aboundant than expected even for relatively large clusters. Another possibility, supported by the studies of Jarrold and co-workers [44] is that fullerene like clusters can form complexes with the presence of sp chains. 

NON-CARBON AND LAYERED FULLERENES. FULLERENE-LIKE CLUSTERS. 

Non-Carbon and Layered Fullerenes. Fullerene-Like Clusters Fullerene Formation Mechanism FuUerene Molecules with Defects Solid Fullerene - Fullerite... 

Here, a first review is provided which summarizes the more recent development framework modified fullerenes like cluster opened structures and heterofullerenes. The key steps for such framework modifications are always defined activations of the fullerene cluster due to specific covalent addition reactions. Therefore, the principles of covalent fullerene chemistry [3-8] will be considered first ... 

Recent theoretical calculations on hypothetical Si fullerene-like clusters with N > 28 showed that they would be unstable. However, the addition of Si atoms inside the cluster (stuffed fullerenes) make them more stable, giving rise to some magic numbers of N, such as 33, 36, 39, 45, 50 [68, 69]. According to Li et al. [70], the most probable structure of Siso would be a distorted truncated icosahedron with Th symmetry instead of L. On the other hand, the existence of clathrate forms of carbon seems possible [71-73]. 

Borafullerenes B2C58, B oCso, Bl2C48, BKP44, Bl8C42, B oClo, and fullerene-like B32, B42 clusters 98KK896. 

A variety of other elemental arsenic forms have been synthesized in laboratories, including amorphous ( black ) elemental arsenic, various arsenic clusters, and even larger fullerene-like cage structures (Zhao et al., 2004 Baruah et al., 2004). The compositions of the clusters are As , where n = 1—5. AS4 or yellow arsenic is the most common form of elemental arsenic in the vapor phase and the bond length between the arsenic atoms in AS4 is about 2.435 A (Zhao et al., 2004 Karttunen, Linnolahti and Pakkanen, 2007), 913. 

Abstract. Geometrical parameters, total energy, heat of formation, energies of HOMO and LUMO orbitals, density of one-electron states (DOS) are determined by using of semi-empirical quantum chemistry PM3-method for isolated molecules Cn, dimers (Cn)2 and cuban-like clusters (Cn)8 for n = 20, 24, 28, 32. The results of calculations allow assuming the existence of polymerized cubic crystal structure on base of all considered small fullerenes. 

TABLE 1. Calculated parameters of fullerene C2o, dimer (C2o)2 and cuban-like cluster (C2o)8... 

Among all the isomers of fullerenes C32 we choice the molecule with cubic point symmetry group Oh. The molecule cage is formed by 12 hexagonal and 6 square faces. The atoms disposed in vertex of squares take part in forming of intermolecular bonds in dimer (C32)2 and cuban-like cluster (C32)s-... 

The first part of the chapter is devoted to non-carbon and fiillerene-like clusters and describes the role of the fullerene molecule in cluster research. The second part addresses one of the most controversial questions concerning the mechanism of formation of the fullerene molecule. The third part reveals the role of of defects of the fullerene molecule and their possible applications. The results of molecular dynamic simulations show the possibility for the production of selected types of defects in the process of atomic implantation. Solid state properties of the fullerene molecule are discussed in the fourth part of the chapter. 

In spite of the repeated recognition of fullerene-like polymorphs [23-25] it has so far been impossible to isolate them in amounts comparable to those obtained for Ceo and C70. There are only a few studies devoted to the fullerene-like structures, based on elements distinct from carbon or silicon [26-28]. The majority of investigations related to non-carbon clusters has been performed on silicon systems, perhaps because of silicon s applications in the microelectronic industry. 

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