Hydrogen fullerenes

A more recent study performed on nC6 and hydrogenated fullerenes presents more detailed effects on hopping frequency, heart rate, appendage movement, and post-abdominal claw curling. The results show intoxication effects, which lead an invertebrate population to be more easily plundered (Lovem et al., 2007). 

MNDO or ab initio calculations (Table 5.3). Further confirmation for the preference of 1,2-addition was established by ab initio calculation of the C-H bond energy in hydrogenated fullerenes [35]. Hybrid density functional theory using the B3LYP functional with the 6-31 G(d,p) basis set leads to the bond energies shown in Table 5.3. The most stable bond is found in 1,2 adducts with a bond energy of 2.86 eV, followed by a bond energy of 2.69 eV in 1,4-adducts. All the other addition patterns such as 1,3 addition or addition to a [5,6] bond lead to less stable C-H bonds (Table 5.3). 

The reaction of fullerenes with the Lewis acid BHj is discussed in Chapter 5. These hydroborations followed by hydrolysis provide access to hydrogenated fullerenes [87]. Also, other Lewis acids have been allowed to react with Cjq and C q [66, 88-91],... 

F. Cataldo and S. Iglesias-Groth (eds.), Fulleranes The Hydrogenated Fullerenes, Carbon Materials Chemistry and Physics 2, DOI 10.1007/978-l-4020-9887-l l, Springer Science+Business Media B.V. 2010... 

Finally, hydrogenated fullerenes have been proposed as carriers of the anomalous microwave emission recently detected by several experiments on the Cosmic Microwave Background (Iglesias-Groth 2005, 2006). In the interstellar medium these molecules should spin with rates of several to tens of gigaHertz, if as expected they have a small dipole moment, then they would emit electric dipole radiation in a frequency range very similar to that observed for the anomalous microwave emission. 

Hydrogenated fullerenes and buckyonions may produce rotationally based electric dipole microwave radiation under the conditions of the diffuse interstellar medium. These molecules are potential carriers for the anomalous Galactic micro-wave emission recently detected by several cosmic microwave experiments. Their precise contribution to this emission should be fully investigated. 

F. Cataldo and S. Iglesias-Groth (eds.), Fulleranes The Hydrogenated Fullerenes,... 

Fig. 3.3 FT-IR spectra (in KBr) of fullerane C6ffH36 (top spectrum) and the soot formed by its thermal decomposition at 630°C under inert atmosphere (bottom spectrum). The four band pattern spectrum at the bottom of the figure at 6.99, 8.45, 17.39 and 19.05 pm is due to C60 fullerene. Thus, fullerane by thermal processing can form back quite easily fullerene which in its turn is able to react with atomic hydrogen forming back hydrogenated fullerene or fullerane...

Mass spectrometric characterization of highly hydrogenated fullerenes showed also that some intermediate products are formed before the cage structure of fulleranes collapses fragmented fulleranes. The name fragmented fullerenes is used when fullerene molecule loses some carbon atoms, thus forming e.g. C58, C56, C54 etc. These molecules can be produced from C60 in the form of atomic clusters in gas phase and were typically observed only by mass spectrometry (Murry et al. 1993 Hathiramani et al. 2000 Dunser et al. 1997). Fragmented fulleranes are stable and could be obtained in bulk amounts, see next section for more details. 

Very recently author of this review successfully hydrogenated fullerenes inside of single walled carbon nanotubes (so called peapods). Evidence of hydrogenation was provided by NMR studies and Raman spectroscopy (Abou-Hamad et al. 2009). 

Meletov KP, Assimopoulos S, Tsilika I, Bashkin IO, Kulakov VI, Khasanov SS, Kourouklis GA (2001) Isotopic and isomeric effects in high-pressure hydrogenated fullerenes studied by Raman spectroscopy. Chem Phys 263 379-388... 

Abstract Fulleranes, the hydrogenated fullerenes C60H36 and C60D36 have been synthesized in n-hexane where they show an absorption maximum at 217 nm in their electronic absorption spectra. Similarly C70H38 and C70D38 show an absorption maximum in n-hexane at 214 nm. 

Calculated spectra for hydrogenated fullerenes have been published in comparison with the unidentified infrared emission bands (Webster 1991 Stoldt et al. 2001). The infrared spectrum of C60H36 has been compared also with the infrared features of other astrophysical objects like the proto-planetary nebulae (Cataldo 2003a, b). An inventory about fullerenes and hydrogenated derivatives in the interstellar... 

Abstract NMR spectroscopy is so far the only analytical technique that has been used to get a detailed structural characterization of hydrogenated fullerenes. A substantial amount of information derived from different NMR experiments can thus be found in the literature for a number of fullerenes hydrogenated to various degrees. These studies have benefitted from the fact that chemical shifts of II and 13C and in some cases also 3He can be used to obtain structural information of these compounds. Such results, together with discussions about different NMR experiments and general considerations regarding sample preparations, are summarized in this chapter. The unique information, both structural and physicochemical, that can be derived from different NMR experiments ensures that this technique will continue to be of central importance in characterization of hydrogenated fullerenes. 

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