Fullerene water molecule

The nature of the additional luminescence in systems with C6o fullerene-water interface remains unknown yet, but we can just advocate that the role of water (or maybe oxygen ion) is essential to formation of this luminescence mechanism. It reflects an existence of high interaction between water and Cgo fullerene molecules. 

Buvari-Barcza and co-workers [77] showed, by comparing several com-plexing agents, that y-CD is the best host for solubilising C6q fullerene in a water environment. The interaction of C6q and y-CD forms a C6o-(y-CD)2 inclusion complex. The analytical data and solid state NMR indicated that the essentially 1 2 complex exists as two different forms. In the violet colored form, unhydrated C60 is included, while in the brownish one, C q is also hydrated. The inner diameter of the y-cyclodextrin is only 0.95 nm while the diameter of C6q is estimated to be 1.0 nm. Because of this dimensional difference, complete inclusion is inconceivable, but the secondary hydroxyls of the y-CD rims can be connected by hydrogen bonds and possibly mediated by water molecules (Fig. 29). 

The results of C solid state NMR experiments on dehydrated and hydrated C6Q-(y-CD)2 complexes prove, not only the general formation of [C6o-(y-CD)2] (H20)x species, but also the hydration of C6q itself, since the data measured for different carbon atoms of C q are definitely non-equivalent in the two cases. In the violet [C6o-(y-CD)2] (H20)x species, the water molecules seem to be connected only to the y-CD domain of the supramolecule, while in the hydrated brown complex, the included fullerene is also hydrated [C6o (H20)y(y-CD)2]-(H20)J. 

Ideal point free nanoelements are fullerenes C o or C70 (Figure 1.11) [4] such structures could be defined as zero-dimensional continua. These elements are symmetric and nearly independent of all external influences. Some nanostmctures in liquids, due to their forms and electrical charges, are also close to ideal point nanoelements. Clusters of water molecules or atoms of metals, are nonideal point nanoelements. 

Rare Earth Encapsulated Fullerenes. Alkali metal encapsulated fullerenes have attracted interest since some of them such as K3C60 exhibit superconductivity at relatively high temperatures. Interesting applications have been found for rare earth metal encapsulated ftiUerene. For example, Gd Cg2 was reported to show enhanced properties as a contrast agent for MRIs. The Gd + ions act as a relaxation mechanism for the proton in water molecules in bodies and strengthen the contrast of MRI images. 

L. Shi and L. Gan, Open-Cage Fullerenes as Tailor-Made Container for a Single Water Molecule,/ Phys. Org. Chem., 2013, 26, 766. 

The other way to introduce fullerenes C60 to biomedium, that we have used, was based on the transfer of these molecules from organic solvent (e.g., toluene) to the water using ultrasound sonication (Scharff et al., 2004). 

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