Homogenous fullerene

Using the C60 suspension prepared from non-homogenized fullerene, the efficacy of inactivation of the vims was much lower compared to the fine suspension. The viral titer in this case decreased by one to two times, suggesting that the efficacy of inhibition of the vims strongly depends on the total surface of the fullerene exposed to oxygen and liquid. 

The effect of isotopical replacement was also investigated for the Ci Csg structure corresponding to the natural contents of the isotope (about 1.1 %). Because of infiingement of symmetry all vibrational frequencies of such molecules became IR active [90]. In line with the case of clusters characterized by large n considered above, the calculations have shown that the intensity of such peaks is very small in comparison with the intensity of the IR modes of a homogeneous fullerene molecule. Therefore, the most typical effect from replacement of one or several C atoms in Cgo is a smoothing of IR peak (about 1/6 from the initial value) corresponding to the vibration mode of Tiu symmetry [90]. 

Relatively homogeneous fullerene LB films can be formed by mixing with arachidic acid [333]. This mixed film was used to construct a heterostructure with a PHT-arachidic acid layer, although no (bi)polaron formation was observed [341]. Donor-acceptor complexes of Cso with tetra(hexadecylthio)-TTF and BEDT-TTF were subjected to LB work. In both cases, multilayer film was formed at the air-water interface. Conductivity values of 4 and 20 S/cm for the tetra-(hexadecylthio)-TTF/C6o and the BEDT-TTF/Ceo system, respectively, were obtained after iodine doping of LB films [342]. 

A new technique to prepare nC60 (fullerene sonication in methanol) has been used, but in this case the cluster sizes are not homogeneous. This preparation permeates the cell membrane of normal and malignant breast epithelial cells (MCF10A and MDA MB 231 or MDA MB 435, respectively) without interfering with cellular events. Also the incubation with high concentration (200ppm) does not adversely impact cell proliferation (Levi et al., 2006). 

A suspension of crystal fullerene C60 (1 mg/ml) in 0.15 M NaCl was used in experiments. To prepare the suspension, 60 mg of crystal fullerene was homogenized with a pestle, followed by sonication in 50 ml of saline for 60 min (5 min sonication/ 10 min interval). A freshly prepared suspension was used in experiments. 

In a separate set of experiments, fullerene was used without preliminary homogenization. 

The radical anion Cw, can also be easily obtained by photoinduced electron transfer from various strong electron donors such as tertiary amines, fer-rocenes, tetrathiafulvalenes, thiophenes, etc. In homogeneous systems back-electron transfer to the reactant pair plays a dominant role resulting in a extremely short lifetime of Qo. In these cases no net formation of Qo is observed. These problems were circumvented by Fukuzumi et al. by using NADH analogues as electron donors [154,155], In these cases selective one-electron reduction of C6o to Qo takes place by the irradiation of C6o with a Xe lamp (X > 540 nm) in a deaerated benzonitrile solution upon the addition of 1-benzyl-1,4-dihydronicoti-namide (BNAH) or the corresponding dimer [(BNA)2] (Scheme 15) [154], The formation of C60 is confirmed by the observation of the absorption band at 1080 nm in the near infrared (NIR) spectrum assigned to the fullerene radical cation. 

Fig. 14 Section of charge density along the six-membered hexagonal ring of C80. The homogeneous ring charge density inside C80 fullerene indicates La2 trajectory connecting the hexagonal ring of icosahedral C80...

Fig. 15 Fitting result of the first pre-Rietveld analysis of Sc2 C66 based on the homogeneous spherical shell charge density model for the fullerene cage. The section MEM charge density of Sc2 C66 based on the pre-Rietveld analysis is inserted. The contour lines are drawn from 0.0 to 3.0 e A-3 with 0.3 e A-3 intervals...

Solar cells devices based on CuPc and C6o fullerene have reached power conversion efficiencies of up to 5% [266,271], the highest efficiency for a Pc-containing solar cell being represented by a tandem cell in which two cells, each of them composed of a mixed donor/acceptor CuPc/C6o layer sandwiched between homogeneous donor and acceptor layers, are coupled (efficiency = 5.7%) [272],... 

The reactivity of the molecular fullerene solid resembles the expected pattern for a homogeneous material. Only a small prereactivity at 700 K indicates that a fullcrcne-oxygen complex [12] is formed as an intermediate stoichiometric compound [15, 105], At 723 K the formation of this compound and the complete oxidation are in a steady state [12, 106, 107] with the consequence of a stable rate of oxidation which is nearly independent of the bum-off of the fullerene solid. This solid transforms prior to oxidation into a disordered polymeric material. The process is an example of the alternative reaction scenario sketched above for the graphite oxidation reaction. The simultaneous oxidation of many individual fullerene molecules. leaving behind open cages with radical centers, is the reason for the polymerization. 

Because of the considerable variety of materials that can be classified as porous, the discussion will be limited to several groups porous silicates and aluminosilicates, porous metal oxides and related compounds, porous polyoxometalates, metal-organic frameworks, porous carbons, carbon nanotubes, and several hybrid materials. All these materials can be viewed as relatively homogeneous from the electrochemical point of view. Metal and metal oxide nanoparticles, organic metals, fullerenes, and dendrimers, which can also be regarded as nanostructured materials, also displaying distinctive electrochemical features, will not be treated here for reasons of brevity, although their appearance in hybrid materials as modifiers for microporous materials will be discussed. 

Carbides Transition Metal Solid-state Chemistry Carbon Fullerenes Carbonyl Complexes of the Transition Metals Carbonylation Processes by Homogeneous Catalysis Cyanide Complexes of the Transition Metals Intercalation Chemistry. 

The scope of the following review is to summarize the radiation chemical studies that are concerned with the radical-induced redox, excitation and alkylation reaction of fullerenes. In particular, the reactivity of fullerenes and functionalized fullerene derivatives are compared in homogeneous and also heterogeneous systems, including micelles, vesicles and guest-host complexes. 

The reduction experiments disclose a noticeable slow-down of the Ceo/Y-CD reduction (k]4 = 2.7 x 10 NT s ), initiated by the bulky (CH3)2 COH radicals, relative to a bimolecular reaction in homogeneous systems (k4 = 8.5 x 10 M s ). In conclusion, the fullerene core is not completely shielded from the aqueous phase and, thus, can be efficiently reduced via hydrated electrons and various a-hydroxyl radicals. 

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