Fullerene cluster

Quite apart from the fullerene cluster molecules, numerous other molecular allotropes of carbon, C , have been discovered in the gases formed by the laser vaporization/supersonic expansion of graphite. The products are detected by mass... 

Other addition reactions are shown in the scheme. Thus, Ceo reacts as an olefin towards [Pt (PPh3)2] to give the t adduct [Pt(>j -C6o)(PPh3)2]. Indeed six centres can simultaneously be coordinated by a single fullerene cluster to give [C6o M(PEt3)2 6], (M = Ni, Pd, Pt), with the 6M arranged octahedrally about the core. Likewise, reaction... 

Brant JA, Labille J, Bottero JY et al. (2006) Characterizing the impact of preparation method on fullerene cluster structure and chemistry. Langmuir. 22 3878-3885. 

Contrary to the electron transfer in organic solvents, the reduction process of functionalized fullerenes in aqueous solutions is very complex. Although some adducts are sufficiently water-soluble (Fig. 22) no reduction could be observed [181,183,187], This is attributed to the irreversible formation of fullerene clusters in aqueous media, which seem to prevent electron transfer. Consequently, efficient triplet-triplet annihilation within the clusters is observed resulting in short triplet lifetimes (< 0.1 (xs compared to microseconds for their monomeric analogue) [182,187],... 

Figure 6 The structures of endohedral fullerene clusters with linear tri- and tetraatomic guest molecules inside C70 ( >5/, ).

Figure 7 The structure of endohedral fullerene clusters with benzene and borazole molecules encapsulated into Cs4 ( >6a).

Much research has been devoted to the insertion of different kinds of crystalline and non crystalline material into the hollow interior of carbon nanotubes. The encapsulated species include fullerenes, clusters, one-dimensional (ID) metal nanowires, binary metal halides, metal oxides, and organic molecules. 

Keywords polymerized fullerenes, clusters and crystal structures, cubic symmetry, quantum-chemical calculations. 

Next, DRF was introduced in the response module of ADF [32] and the local field problem was reformulated and used to study solvent effects on the NLO properties of water, acetonitrile [26], p-nitroanilinc (pNA) [169] and fullerene clusters. Here we summarize results for water and pNA since they are representative of the method. 

For carbon, it is of course also tempting to study clusters of clusters, namely aggregation of C60 fullerenes [67-69]. This is not really a molecular cluster application since the inner structure of the fullerene, leading to dependence of the particle interaction on relative particle orientation, is largely or completely ignored. The Pacheco-Ramalho empirical potential is used frequently, and fairly large clusters up to n=80 are studied. There appears to be agreement that small fullerene clusters are icosahedral in this model. In contrast to LJ clusters, however, the transition to decahedral clusters appears to occur as early as at n=17 the three-body term of the potential is found to be responsible for this [67]. 

Intercalation compounds of alkali metals. These contain alkali metal ions occupying interstitial sites between fullerene clusters. 

Kongkanand A., Kuwabata S. and Fukuzumi S. (2005), Enhancement of light-energy conversion efficiency by multi-porphyrin arrays of porphyrin-peptide oligomers with fullerene clusters , J. Phys. Chem. B 109, 19-23. 

Use of high-resolution scanning electron microscopy (SEM) allowed the uncovering of a further substructure in these polymer-fullerene blends, besides some larger fullerene clusters (see Fig. 24) MDMO-PPV nanospheres representing a coiled polymer conformation were detected together with some solvent-dependent amount of PCBM fullerenes [55,60-62,137]. 

As could already be inferred from the cross-sectional SEM images, the fullerene clusters are in fact surroimded by a polymer-rich skin layer [55,60]. Using Kelvin probe force microscopy Hoppe et al. were able to confirm this by the detection of a considerably increased work function on top of the polymer... 

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