Artículos de revistas: "Fullerene"

1

Lin, Hao-Sheng y Yutaka Matsuo. "Functionalization of [60]fullerene through fullerene cation intermediates". Chemical Communications 54, n.º 80 (2018): 11244–59. http://dx.doi.org/10.1039/c8cc05965a.

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Fullerene cations, namely [60]fullerene radical cation (C₆₀˙⁺) and organo[60]fullerenyl cation (RC₆₀⁺), open paths for the efficient derivatization of a great variety of fullerenes.

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2

Lun-Fu, Aleksandr V., Alexey M. Bubenchikov, Mikhail A. Bubenchikov y Vyacheslav A. Ovchinnikov. "Numerical Simulation of Interaction between Kr+ Ion and Rotating C60 Fullerene towards for Nanoarchitectonics of Fullerene Materials". Crystals 11, n.º 10 (6 de octubre de 2021): 1204. http://dx.doi.org/10.3390/cryst11101204.

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Dynamics of charged fullerene in a surface layer of fullerite is studied under the influence of neutral or charged particles of the gas phase surrounding the fullerite material. The translational displacements of the nodes of the crystal lattice structure are determined by the equations of motion of the centers of mass of fullerenes. Central fullerene, which is described as a discrete set of sixty carbon atoms, plays a special role in the presented mathematical model. Angular oscillations and rotations of the central fullerene are described by the dynamic Euler equations. All other fullerenes have a centrally symmetric field of the potential of interaction with the surrounding atoms and molecules. In this regard, we use the hybrid discrete–continuous mathematical model with four potentials that describe the interactions between the surrounding fullerenes, smoothed fullerene and an atom, a pair of atoms, and electric charges. The results of a numerical study of influence of the Coulomb interaction on the rotational and translational motion of the C60 fullerene are presented.

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3

Pacor, Sabrina, Alberto Grillo, Luka Đorđević, Sonia Zorzet, Marianna Lucafò, Tatiana Da Ros, Maurizio Prato y Gianni Sava. "Effects of Two Fullerene Derivatives on Monocytes and Macrophages". BioMed Research International 2015 (2015): 1–13. http://dx.doi.org/10.1155/2015/915130.

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Two fullerene derivatives (fullerenes1and2), bearing a hydrophilic chain on the pyrrolidinic nitrogen, were developed with the aim to deliver anticancer agents to solid tumors. These two compounds showed a significantly different behaviour on human neoplastic cell linesin vitroin respect to healthy leukocytes. In particular, the pyrrolidinium ring on the fullerene carbon cage brings to a more active compound. In the present work, we describe the effects of these fullerenes on primary cultures of human monocytes and macrophages, two kinds of immune cells representing the first line of defence in the immune response to foreign materials. These compounds are not recognized by circulating monocytes while they get into macrophages. The evaluation of the pronecrotic or proapoptotic effects, analysed by means of analysis of the purinergic receptor P2X7 activation and of ROS scavenging activity, has allowed us to show that fullerene2, but not its analogue fullerene1, displays toxicity, even though at concentrations higher than those shown to be active on neoplastic cells.

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4

Suvorov, S. V., A. V. Severiuchin y A. V. Vakhrushev. "The effect of the angle of «meeting» of fullerite C60 with a solid substrate on the deposition process". PNRPU Mechanics Bulletin, n.º 3 (15 de diciembre de 2020): 90–97. http://dx.doi.org/10.15593/perm.mech/2020.3.09.

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Carbon forms a large number of allotropic forms, one of which is fullerene. Fullerene is a convex closed polyhedron with carbon atoms at its vertices. The most common is fullerene, consisting of 60 carbon atoms and designated - C60. In turn, fullerenes are able to agglomerate, forming a molecular crystal - fullerite. In the interaction of fullerite C60 with a solid, it is possible to deposit on the surface of the body both whole fullerite and the fullerenes that form it. The interaction process in the C60 fullerite system - the substrate of a solid, and then on - the fullerite - substrate system - is multi-parameter. So, when modeling the interaction of fullerite with a substrate, the following were taken into account: the temperature of the system - 300, 700, 1150 K; the speed of fullerite movement is 0.005, 0.01, 0.02 Å / fs. In addition, in the study, we varied the angle between the fullerite velocity vector and the normal to the contact surface of the substrate, called the “meeting angle”. An iron crystal Fe (100) was modeled as a solid body substrate, as one of the most common structural materials. Fullerite C60 was in contact with the solid substrate with its face. Computer simulation of the process of contact of fullerite C60 with the substrate was carried out in the LAMMPS software package. The main result of this study is to determine the effect of the angle of “meeting” of C60 fullerite in contact with a solid substrate, which will significantly complement the overall picture of the process of C60 fullerite deposition. In turn, this can allow the creation of various films and wear-resistant coatings on the surface of materials.

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5

Bubenchikov, Alexey, Mikhail Bubenchikov, Dmitriy Mamontov y Alexandr Lun-Fu. "Md-Simulation of Fullerene Rotations in Molecular Crystal Fullerite". Crystals 9, n.º 10 (25 de septiembre de 2019): 496. http://dx.doi.org/10.3390/cryst9100496.

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The present paper describes rotations of C60 fullerene molecules in the solid phase of a fullerite. The conducted studies show that these relatively large molecules rotate according to the same laws as macroscopic bodies, i.e., according to the laws of classical mechanics. The performed calculations confirm that fullerene rotations do not cause friction. We suggest a method for a strong increase in the internal energy of the material that does not lead to its destruction. It is theoretically shown that in standard fullerite, in the absence of electric and magnetic fields, fullerene rotations occur with an average angular frequency of 0.34·× 1012 rad·s−1, which is consistent with the experimental data obtained using nuclear magnetic resonance. By means of calculations, we found that alternating magnetic fields of a certain configuration wind fullerenes encapsulated by iron. In this case, two temperatures arise in the fullerite crystal: a high rotational temperature and a vibrational temperature close to normal. For the purpose of determining this velocity, as well as the nature of rotations, the present paper suggests a way of integrating the dynamic Euler equations for the projections of a molecule’s angular velocity vector onto the coordinate axes associated with the fullerene. The stages of computer simulation of fullerene movements, which was carried out without using previously developed packages of molecular-dynamic modelling, are consistently described.

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6

Sabirov, Denis Sh. "Polarizability as a landmark property for fullerene chemistry and materials science". RSC Adv. 4, n.º 85 (2014): 44996–5028. http://dx.doi.org/10.1039/c4ra06116k.

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The review summarizes data on dipole polarizability of fullerenes and their derivatives, covering the most widespread classes of fullerene-containing molecules (fullerenes, fullerene exohedral derivatives, fullerene dimers, endofullerenes, fullerene ions, and derivatives with ionic bonds).

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7

Chen, Guoping, Lok Kumar Shrestha y Katsuhiko Ariga. "Zero-to-Two Nanoarchitectonics: Fabrication of Two-Dimensional Materials from Zero-Dimensional Fullerene". Molecules 26, n.º 15 (30 de julio de 2021): 4636. http://dx.doi.org/10.3390/molecules26154636.

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Nanoarchitectonics of two-dimensional materials from zero-dimensional fullerenes is mainly introduced in this short review. Fullerenes are simple objects with mono-elemental (carbon) composition and zero-dimensional structure. However, fullerenes and their derivatives can create various types of two-dimensional materials. The exemplified approaches demonstrated fabrications of various two-dimensional materials including size-tunable hexagonal fullerene nanosheet, two-dimensional fullerene nano-mesh, van der Waals two-dimensional fullerene solid, fullerene/ferrocene hybrid hexagonal nanosheet, fullerene/cobalt porphyrin hybrid nanosheet, two-dimensional fullerene array in the supramolecular template, two-dimensional van der Waals supramolecular framework, supramolecular fullerene liquid crystal, frustrated layered self-assembly from two-dimensional nanosheet, and hierarchical zero-to-one-to-two dimensional fullerene assembly for cell culture.

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8

Manchado, A., J. J. Díaz-Luis, D. A. García-Hernández y F. Cataldo. "A Catalog of Diffuse Interstellar Bands in Fullerene-Containing Planetary Nebulae". Proceedings of the International Astronomical Union 9, S297 (mayo de 2013): 223–25. http://dx.doi.org/10.1017/s1743921313015901.

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AbstractLarge fullerenes and fullerene-based molecules have been proposed as carriers of diffuse interstellar bands (DIBs). The recent detection of the most common fullerenes (C60 and C70) around some Planetary Nebulae (PNe) now enable us to study the DIBs in fullerene-rich space environments. We have studied the presence of DIBs in the optical spectra (~3300-9400 Å) of two fullerene-containing PNe (Tc 1 and M 1-20). Special attention is given to DIBs which are found to be unusually intense in fullerene-containing PNe; several of these DIBS have not previously been reported. Fullerenes larger than C60 (and C70) and multishell fullerenes may be possible candidate carriers for the unusual DIBs seen in fullerene-rich environments.

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9

Iyoda, Masahiko, Hideyuki Shimizu, Shinobu Aoyagi, Hiroshi Okada, Biao Zhou y Yutaka Matsuo. "Structures and properties of Saturn-like complexes composed of oligothiophene macrocycle with methano[60]fullerene and [70]fullerene". Canadian Journal of Chemistry 95, n.º 3 (marzo de 2017): 315–19. http://dx.doi.org/10.1139/cjc-2016-0461.

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π-Expanded oligothienylene macrocycle with a large inner cavity incorporates fullerenes such as methano[60]fullerene (C61H2) and [70]fullerene (C70) inside to form Saturn-like complexes. Although the oligothiophene macrocycle weakly interacts with fullerenes in solution, it forms stable Saturn-like fullerene complexes in the solid state. X-ray analysis of the Saturn-like complexes exhibited short contacts between the sulfur atoms of the oligothiophene macrocycle and fullerene carbons, which hinder the rotation of fullerenes. As a result, the non-covalent interaction between the oligothiophene macrocycle and fullerenes was employed in crystal structure determination of fullerenes. UV–vis–NIR spectra of the Saturn-like complexes showed weak donor–acceptor interaction between the oligothiophene macrocycle and fullerenes.

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10

Cataldo, F., D. A. García-Hernández, A. Manchado y S. Iglesias-Groth. "Spectroscopy of Fullerenes, Fulleranes and PAHs in the UV, Visible and Near Infrared Spectral Range". Proceedings of the International Astronomical Union 9, S297 (mayo de 2013): 294–96. http://dx.doi.org/10.1017/s1743921313016025.

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AbstractThe spectra of fullerenes C60 and C70, higher fullerenes C76, C78 and C84 and hydrogenated fullerenes (fulleranes) were studied in laboratory in the UV and in the visible spectral range and could be used for searching and recognizing these molecules in space. Furthermore, the radical cation spectra of all the mentioned fullerene series and also of a series of large and very large polycyclic aromatic hydrocarbons (PAHs) were generated in the laboratory and studied in the near infrared spectral range.

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11

Matsuo, Yutaka y Hao-Sheng Lin. "(Invited) Evaporable Fullerene-Fused Ketone Via One-Step Direct Oxidation of Alkoxy to Ketone: Fullerene As a Redox Active Pendant". ECS Meeting Abstracts MA2022-01, n.º 11 (7 de julio de 2022): 812. http://dx.doi.org/10.1149/ma2022-0111812mtgabs.

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We developed a direct oxidation reaction from a methoxy group to a keto group using a mild oxidizing agent with the aid of an oxidizable fullerene pendant. By using this key reaction, we developed a fullerene derivative that is stable even at high temperatures of 400 deg-C or higher and can be used for vacuum deposition to make thin films in organic electronic devices. A highly efficient CuBr2 promoted one-step direct oxidation of alkoxy indano[60]fullerenes to [60]fullerene-fused ketones is showcased. It is shown that the fullerene can behave as an electron-pool controlling the electron transfer to trigger the direct oxidation of alkoxy. This electron-pool for the direct oxidation mainly involves two steps: 1) C60selectively transferred single electron to Cu(II) to afford C60 •+; 2) generated C60 •+ attracts electron density from the neighboring C–H bond, which is the key for initiating the direct oxidation of alkoxy. Accordingly, conventional non-fullerene functionalized alkoxy groups understandably failed to undergo one-step direct oxidation. Encouragingly, compared with current synthetic protocols for fullerenyl ketones including electrochemical synthesis, organometal-catalyzed synthesis, and photochemical synthesis, the presented one-step direct oxidation of alkoxy exhibited advantages such as facile processing procedures, highly scalable yields and low cost, for the efficient production of [60]fullerene-fused ketones, which can provide an efficient synthetic strategy to match up the high synthetic demands of fullerenyl ketone materials applied in organic and perovskite solar cells. Reference: H.-S. Lin, Y. Ma, R. Xiang, S. Manzhos, I. Jeon, S. Maruyama, Y. Matsuo, Communications Chemistry 2021, 4, 74.

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12

Chen, Guoping, Biswa Nath Bhadra, Linawati Sutrisno, Lok Kumar Shrestha y Katsuhiko Ariga. "Fullerene Rosette: Two-Dimensional Interactive Nanoarchitectonics and Selective Vapor Sensing". International Journal of Molecular Sciences 23, n.º 10 (13 de mayo de 2022): 5454. http://dx.doi.org/10.3390/ijms23105454.

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The simplicity of fullerenes as assembled components provides attractive opportunities for basic understanding in self-assembly research. We applied in situ reactive methods to the self-assembly process of C60 molecules with melamine/ethylenediamine components in solution, resulting in a novel type of fullerene assemblies, micron-sized two-dimensional, amorphous shape-regular objects, fullerene rosettes. ATR–FTIR spectra, XPS, and TGA results suggest that the melamine/ethylenediamine components strongly interact and/or are covalently linked with fullerenes in the fullerene rosettes. The broad peak for layer spacing in the XRD patterns of the fullerene rosettes corresponds roughly to the interdigitated fullerene bilayer or monolayer of modified fullerene molecules. The fullerene rosettes are made from the accumulation of bilayer/monolayer assemblies of hybridized fullerenes in low crystallinity. Prototype sensor systems were fabricated upon immobilization of the fullerene rosettes onto surfaces of a quartz crystal microbalance (QCM), and selective sensing of formic acid was demonstrated as preliminary results for social-demanded toxic material sensing. The QCM sensor with fullerene rosette is categorized as one of the large-response sensors among reported examples. In selectivity to formic acids against basic guests (formic acid/pyridine >30) or aromatic guests (formic acid/toluene >110), the fullerene rosette-based QCM sensor also showed superior performance.

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13

Pérez, Emilio M. y Nazario Martín. "Molecular tweezers for fullerenes". Pure and Applied Chemistry 82, n.º 3 (14 de febrero de 2010): 523–33. http://dx.doi.org/10.1351/pac-con-09-09-27.

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The search for molecular receptors capable of forming stable associates with fullerenes is a very active field of research in fullerene chemistry, with the purification from fullerite and the self-assembly of nanoscale electronic devices as driving forces. The construction of bivalent, tweezer-like receptors featuring two recognizing units connected through a spacer is one of the most successful design strategies employed in this field. Here, we present an overview of the most significant examples of these “molecular tweezers” for fullerenes.

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Barrera, E. V., J. Sims y D. L. Callahan. "Development of fullerene-reinforced aluminum". Journal of Materials Research 10, n.º 2 (febrero de 1995): 366–71. http://dx.doi.org/10.1557/jmr.1995.0366.

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Powder metallurgy and casting have been used to produce aluminum with 1.3, 4, and 8 vol. % fullerene additions. Fullerene extract was mixed with Al and heat-treated to obtain various levels of dispersion of the fullerenes. Intergranular dispersion of stable fullerenes was accomplished by both powder metallurgy and casting; however, x-ray diffraction indicated the formation of some Al4C3. Homogeneous dispersion did not occur because of limited diffusion in the solid state or limited solubility of fullerene in Al in the liquid state. Enhancements in hardness over that for Al were observed yet were not comparable to precipitation hardened Al alloys since a less homogeneous dispersion was achieved. Interest in Al having fullerene additions is for development of fullerene strengthened materials where fullerenes act as nanosize dispersoids for dispersion strengthening of metals or as a lightweight reinforcement in metal-matrix composites.

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15

Nisoh, Nililla, Viwan Jarerattanachat, Mikko Karttunen y Jirasak Wong-ekkabut. "Fullerenes’ Interactions with Plasma Membranes: Insight from the MD Simulations". Biomolecules 12, n.º 5 (26 de abril de 2022): 639. http://dx.doi.org/10.3390/biom12050639.

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Understanding the interactions between carbon nanoparticles (CNPs) and biological membranes is critically important for applications of CNPs in biomedicine and toxicology. Due to the complexity and diversity of the systems, most molecular simulation studies have focused on the interactions of CNPs and single component bilayers. In this work, we performed coarse-grained molecular dynamic (CGMD) simulations to investigate the behaviors of fullerenes in the presence of multiple lipid components in the plasma membranes with varying fullerene concentrations. Our results reveal that fullerenes can spontaneously penetrate the plasma membrane. Interestingly, fullerenes prefer to locate themselves in the region of the highly unsaturated lipids that are enriched in the inner leaflet of the plasma membrane. This causes fullerene aggregation even at low concentrations. When increasing fullerene concentrations, the fullerene clusters grow, and budding may emerge at the inner leaflet of the plasma membrane. Our findings suggest by tuning the lipid composition, fullerenes can be loaded deeply inside the plasma membrane, which can be useful for designing drug carrier liposomes. Moreover, the mechanisms of how fullerenes perturb multicomponent cell membranes and how they directly enter the cell are proposed. These insights can help to determine fullerene toxicity in living cells.

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Sokolovska, Lība, Maksims Čistjakovs, Alīna Sultanova y Modra Murovska. "Aqueous C60 Fullerene Solution Effects on Cell Viability". Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. 75, n.º 2 (1 de abril de 2021): 86–91. http://dx.doi.org/10.2478/prolas-2021-0014.

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Abstract Fullerenes are carbon nanoparticles with the ability to quench reactive oxygen species. The biomedical potential of fullerenes is diminished by their low solubility in water, but many approaches have been developed to bypass this problem, like chemical modification of the carbon cage and the use of the solvent exchange method to transfer fullerenes from one solvent to the other. These two approaches were used in this study. Carboxylated fullerene aqueous solution was acquired using solvent exchange method transferring fullerene nanoparticles (C60) from toluene to water. Effects of varying concentration (0.5, 1, 1.5, 2, 2.5, 3, 5, 10 µM) of aqueous fullerene solution on cell viability and their antioxidative capabilities were evaluated on PC-3 and on monocytes isolated from a blood donor using Resazurin Cell Viability Assay. PC-3 cell viability was drastically affected by the 10 µM fullerene solution but remained relatively stable when treated with other concentrations even after longer periods of incubation with resazurin dye. Elevated cell viability was observed in monocytes treated with various fullerene concentrations, possibly indicative of fullerene protective activity against oxidative stress.

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Khamatgalimov, Ayrat R. y Valeri I. Kovalenko. "Substructural Approach for Assessing the Stability of Higher Fullerenes". International Journal of Molecular Sciences 22, n.º 7 (4 de abril de 2021): 3760. http://dx.doi.org/10.3390/ijms22073760.

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This review describes the most significant published results devoted to the study of the nature of the higher fullerenes stability, revealing of correlations between the structural features of higher fullerene molecules and the possibility of their producing. A formalization of the substructure approach to assessing the stability of higher fullerenes is proposed, which is based on a detailed analysis of the main structural features of fullerene molecules. The developed substructure approach, together with the stability of the substructures constituting the fullerene molecule, helps to understand deeper the features of the electronic structure of fullerenes.

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Konarev, Dmitri V., Salavat S. Khasanov, Gunzi Saito y Rimma N. Lyubovskaya. "Fullerene complexes with cobalt(II) tetraphenylporphyrin: from molecular to ionic crystals". Journal of Porphyrins and Phthalocyanines 07, n.º 12 (diciembre de 2003): 801–6. http://dx.doi.org/10.1142/s1088424603000999.

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The complexes of cobalt(II) tetraphenylporphyrin ( Co II TPP ) with fullerenes C 60, C 70 and C 60( CN )2 are presented. It is shown that Co II TPP forms complexes with fullerenes in different solvents: [ Co II TPP •fullerene•solvent] ( solvent = C 6 H 6, C 6 H 5 Me , C 6 H 4 Cl 2, CS 2, CHCl 3). The use of additional donors ( Cp 2 Fe , Cr 0( C 6 H 6)2, and TDAE ) in the synthesis of Co II TPP /fullerene complexes allows one to obtain multi-component complexes ranging from neutral [( Co II TPP • Py )2• Cp 2 Fe • fullerene • solvent ] to ionic [ Co II TPP •( D 2•+)•( fullerene •−)• solvent ] ( D 2 = Cr I( C 6 H 6)2, TDAE ). The interaction of Co II TPP with neutral and negatively charged fullerenes is considered. The neutral Co II TPP /fullerene complexes are characterized by a secondary M…C(fullerene) bonding with the shortest Co … C contacts in the 2.69-2.82 Å range and noticeable changes in the electronic structure of the parent components. At the same time, σ-bonding is observed in ionic complexes between Co II TPP and fullerene radical anions with the shortened Co … C contacts being in the 2.28-2.32 Å range. The resulting ( Co II TPP •fullerene−) anions are diamagnetic. The σ-bonding is relatively weak and the ( Co II TPP •fullerene−) anions begin to dissociate above 200 K.

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HASHIZUME, T. y T. SAKURAI. "FULLERENES ADSORPTION ON Cu(111) AND Ag(111) SURFACES". Surface Review and Letters 03, n.º 01 (febrero de 1996): 905–13. http://dx.doi.org/10.1142/s0218625x96001637.

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Initial stage adsorption and film growth of C 60, C 70, C 60(x) C 70(1−x), and Sc 2@ C 84 fullerene molecules on Cu (111) and Ag (111) surfaces have been investigated by field-ion scanning tunneling microscopy. Fullerene molecules are mobile on the terrace and initially segregate to the step edges. A well-ordered monolayer films form with a close-packed arrangement upon annealing the fullerence-covered surfaces. The (4×4) phases form in the case of the C 60, C 70, and C 60(x) C 70(1−x) adsorption on the Cu (111)-(1×1) surface, indicating a strong interaction between the Cu substrate and fullerenes. Intramolecular structures of the C 60 and C 70 molecules are observed and interpreted as the mappings of the local electron density of states. On the Ag (111) surface, C 60 and Sc 2@ C 84 monolayer films show several phases that have almost identical nearest neighbor distance but are rotated from each other, indicating weaker interaction between the Ag substrate and fullerenes compared with the case of Cu .

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Silant'ev A. V. "Energy Spectrum and Optical Absorption Spectraof endohedral Fullerenes Lu-=SUB=-3-=/SUB=-N\@C-=SUB=-80-=/SUB=- and Y-=SUB=-3-=/SUB=-N\@C-=SUB=-80-=/SUB=-within the Hubbard Model". Physics of the Solid State 64, n.º 2 (2022): 287. http://dx.doi.org/10.21883/pss.2022.02.52978.213.

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Anticommutator Green's functions and energy spectra of fullerene C80,endohedral fullerenes Lu3N@C80 and Y3N@C80 with the Ih symmetry groups have been obtained in an analytical form within the Hubbard model and static fluctuation approximation. The energy states have been classified using the methods of group theory, and the allowed transitions in the energy spectra of molecules C80, Lu3N@C80 andY3N@C80 have been determined. On the basis ofthese spectra, an interpretation of experimentally observed opticalabsorption bands endohedral fullerenes Lu3N@C80 andY3N@C80. Keywords: Hubbard model, Green's functions, energy spectrum,nanosystems, fullerene C80, endohedral fullerene Lu3N@C80, endohedral fullerene Y3N@C80.\

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Keszler, Anna Mária, Éva Kováts, Eszter Bódis, Zoltán Károly y János Szépvölgyi. "Effect of Metallic and Non-Metallic Additives on the Synthesis of Fullerenes in Thermal Plasma". Condensed Matter 7, n.º 3 (30 de junio de 2022): 44. http://dx.doi.org/10.3390/condmat7030044.

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The effect of metallic (Fe, Cu, Co, Ni, Ti) and non-metallic additives (Si, B) on the formation of fullerenes from graphite powders was studied in radiofrequency (RF) thermal plasma. The main component of the synthesized fullerene mixtures was C60, but higher fullerenes (C70, C82, and C84) could be detected as well. Fe and Cu additives increased the fullerene content in the soot. In contrast, the fullerene formation decreased in the presence of Ti, Si, and B as compared to the synthesis without additives. However, Ti and B addition enhanced the formation of higher fullerenes. We provide experimental evidence that decreasing the reactor pressure results in a lower yield of fullerene production, in accordance with thermodynamic calculations and numerical simulations published earlier. In the presence of titanium, a significant quantity of TiC was also formed as a by-product. The fullerene mixture synthesized with boron additives showed higher stability during storage in ambient conditions as compared to other samples.

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Yao, Sai, Xingzhong Yuan, Longbo Jiang, Ting Xiong y Jin Zhang. "Recent Progress on Fullerene-Based Materials: Synthesis, Properties, Modifications, and Photocatalytic Applications". Materials 13, n.º 13 (30 de junio de 2020): 2924. http://dx.doi.org/10.3390/ma13132924.

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Solar light is an inexpensive energy source making up for energy shortage and solving serious environmental problems. For efficient utilization of solar energy, photocatalytic materials have attracted extensive attention over the last decades. As zero-dimensional carbon nanomaterials, fullerenes (C60, C70, etc.) have been extensively investigated for photocatalytic applications. Due to their unique properties, fullerenes can be used with other semiconductors as photocatalyst enhancers, and also as novel photocatalysts after being dispersed on non-semiconductors. This review summarizes fullerene-based materials (including fullerene/semiconductors and fullerene/non-semiconductors) for photocatalytic applications, such as water splitting, Cr (VI) reduction, pollutant degradation and bacterial disinfection. Firstly, the optical and electronic properties of fullerene are presented. Then, recent advances in the synthesis and photocatalytic mechanisms of fullerene-based photocatalysts are summarized. Furthermore, the effective performances of fullerene-based photocatalysts are discussed, mainly concerning photocatalytic H2 generation and pollutant removal. Finally, the current challenges and prospects of fullerene-based photocatalysts are proposed. It is expected that this review could bring a better understanding of fullerene-based photocatalysts for water treatment and environmental protection.

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Blagov, Maksim A., Nataliya G. Spitsina y Sergei V. Konovalikhin. "CO-CRYSTALLIZATION OF C60 AND С70 FULLERENES IN CRYSTAL-SOLVATE [(C70)X+(С60)Y]• TMTSeF•2(C6H6) (х+у=3)". IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 59, n.º 9 (17 de julio de 2018): 21. http://dx.doi.org/10.6060/tcct.20165909.3y.

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The compexation of (С70/C60) fullerenes with organic p-donor of electrons tetramethyl-(tetra selenium)fulvalene (TMTSeF) in benzene (С6Н6) was studied. Comparison of experimental and calculated X-ray patterns showed that in the investigated single crystals of [(C70)x+(С60)y]· TMTSeF·2(C6H6) (х+у=3) (1) С70 and C60 fullerens are co-crystallized. IR spectral data and electroconductivity of 1 indicate the absence of the charge transfer on fullerene molecule for complexes under study.

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Piotrovsky, Levon B., Elena V. Litasova y Marina A. Dumpis. "Why do we need fullerenes today?" Reviews on Clinical Pharmacology and Drug Therapy 17, n.º 2 (9 de agosto de 2019): 5–15. http://dx.doi.org/10.17816/rcf1725-15.

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The review focuses on the possibilities and prospects of the use of fullerenes and their derivatives in cosmetics, the only industrial area where fullerenes have found practical application today. Based on the literary data and the results of their own experiments, the authors substantiate the safety of using fullerene for living organisms, as well as the usefulness of introducing fullerene as antioxidant in cosmetic compositions. Other useful properties of fullerene used in cosmetics and dermatology are discussed.

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25

Silant'ev A. V. "Energy Spectrum and Optical Absorption Spectra of endohedral Fullerenes Lu-=SUB=-3-=/SUB=-N\@C-=SUB=-80-=/SUB=- and Y-=SUB=-3-=/SUB=-N\@C-=SUB=-80-=/SUB=- within the Hubbard Model". Physics of the Solid State 64, n.º 2 (2022): 287. http://dx.doi.org/10.21883/pss.2022.02.53979.213.

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Anticommutator Green's functions and energy spectra of fullerene C80, endohedral fullerenes Lu3N@C80 and Y3N@C80 with the Ih symmetry groups have been obtained in an analytical form within the Hubbard model and static fluctuation approximation. The energy states have been classified using the methods of group theory, and the allowed transitions in the energy spectra of molecules C80, Lu3N@C80 and Y3N@C80 have been determined. On the basis of these spectra, an interpretation of experimentally observed optical absorption bands endohedral fullerenes Lu3N@C80 and Y3N@C80. Keywords: Hubbard model, Green's functions, energy spectrum, nanosystems, fullerene C80, endohedral fullerene Lu3N@C80, endohedral fullerene Y3N@C80.

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26

Katin, Konstantin P., Alexey I. Kochaev, Savas Kaya, Fadoua El-Hajjaji y Mikhail M. Maslov. "Ab Initio Insight into the Interaction of Metal-Decorated Fluorinated Carbon Fullerenes with Anti-COVID Drugs". International Journal of Molecular Sciences 23, n.º 4 (21 de febrero de 2022): 2345. http://dx.doi.org/10.3390/ijms23042345.

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We theoretically investigated the adsorption of two common anti-COVID drugs, favipiravir and chloroquine, on fluorinated C60 fullerene, decorated with metal ions Cr3+, Fe2+, Fe3+, Ni2+. We focused on the effect of fluoridation on the interaction of fullerene with metal ions and drugs in an aqueous solution. We considered three model systems, C60, C60F2 and C60F48, and represented pristine, low-fluorinated and high-fluorinated fullerenes, respectively. Adsorption energies, deformation of fullerene and drug molecules, frontier molecular orbitals and vibrational spectra were investigated in detail. We found that different drugs and different ions interacted differently with fluorinated fullerenes. Cr3+ and Fe2+ ions lead to the defluorination of low-fluorinated fullerenes. Favipiravir also leads to their defluorination with the formation of HF molecules. Therefore, fluorinated fullerenes are not suitable for the delivery of favipiravir and similar drugs molecules. In contrast, we found that fluorine enhances the adsorption of Ni2+ and Fe3+ ions on fullerene and their activity to chloroquine. Ni2+-decorated fluorinated fullerenes were found to be stable and suitable carriers for the loading of chloroquine. Clear shifts of infrared, ultraviolet and visible spectra can provide control over the loading of chloroquine on Ni2+-doped fluorinated fullerenes.

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27

Kintigh, Jeremy, Jonathan B. Briggs, Kristine Letourneau y Glen P. Miller. "Fulleranes produced via efficient polyamine hydrogenations of [60]fullerene, [70]fullerene and giant fullerenes". Journal of Materials Chemistry 17, n.º 44 (2007): 4647. http://dx.doi.org/10.1039/b709354c.

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28

Uchida, Noriyuki, Masayoshi Yanagi y Hiroki Hamada. "Fullerene Nanoparticles Using Technol PG for Inexpensive Preparation". Natural Product Communications 17, n.º 7 (julio de 2022): 1934578X2211155. http://dx.doi.org/10.1177/1934578x221115556.

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Fullerene has attracted much attention for applications in biomaterials because of its high antioxidant activity. In this study, C60 and C70 fullerenes were mixed with a commercially available anionic phospholipid mixture, Technol PG, and sodium cholate, resulting in effective dispersion of the fullerenes to give small-sized fullerene nanoparticles.

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29

Zhen, Junfeng, Weiwei Zhang, Yuanyuan Yang y Qingfeng Zhu. "Laboratory study on the fullerene–PAH-derived cluster cations in the gas phase". Monthly Notices of the Royal Astronomical Society 490, n.º 3 (3 de octubre de 2019): 3498–507. http://dx.doi.org/10.1093/mnras/stz2680.

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ABSTRACT It is possible that fullerene–polycyclic aromatic hydrocarbon (PAH) clusters or associations of fullerenes with PAHs contain a large fraction of interstellar fullerenes in the interstellar medium. Herein, we report the formation and photofragmentation behaviour of fullerene–PAH derivatives, fullerene/9-vinylanthracene (C16H12) and fullerene/9-methylanthracene (C15H12) cluster cations. Experiments are carried out using a quadrupole ion trap in combination with time-of-flight mass spectrometry in the gas phase. The results show that fullerene (C60)/9-vinylanthracene (e.g. [(C16H12)3C60]+), fullerene (C56 and C58)/9-vinylanthracene (e.g. [(C16H12)4C56]+ and [(C16H12)4C58]+), fullerene (C60)/9-methylanthracene (e.g. [(C15H12)3C60]+), and fullerene (C56 and C58)/9-methylanthracene (e.g. [(C15H12)4C56]+ and [(C15H12)4C58]+) cluster cations, i.e. large fullerene-derived molecules, are formed in the gas phase through the ion–molecule reaction pathway. With irradiation, all fullerene–PAH-derived cluster cations lose their monomolecular groups without other fragmentation channels (e.g. dehydrogenation). The structure of newly formed fullerene–PAH-derived cluster cations and the bond energy for these adduction formation pathways are investigated with theoretical calculations. The obtained results provide a general molecular growth route towards large fullerene–PAH derivatives (e.g. large fullerene-derived molecules) with functional PAHs in a bottom-up formation process and insights into the effect of functional groups (e.g. vinyl, –C2H3, and methyl, –CH3) on their formation and photoevolution behaviours. In addition, the fullerene–PAH-derived clusters (from 83 to 170 atoms in total, or ∼2 nm in size) offer a good model of carbon dust grains, and the relevance to the nanometre-sized carbon dust grain in space is briefly discussed.

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30

Powell, W. H., F. Cozzi, G. P. Moss, C. Thilgen, R. J. R. Hwu y A. Yerin. "Nomenclature for the C60-Ih and C70-D5h(6) fullerenes (IUPAC Recommendations 2002)". Pure and Applied Chemistry 74, n.º 4 (1 de enero de 2002): 629–95. http://dx.doi.org/10.1351/pac200274040629.

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Fullerenes are a new allotrope of carbon characterized by a closed-cage structure consisting of an even number of three-coordinate carbon atoms devoid of hydrogen atoms. This class was originally limited to closed-cage structures with 12 isolated five-membered rings, the rest being six-membered rings. Although it was recognized that existing organic ring nomenclature could be used for these structures, the resulting names would be extremely unwieldy and inconvenient for use. At the same time it was also recognized that established organic nomenclature principles could be used, or adapted, to provide a consistent nomenclature for this unique class of compounds based on the class name fullerene. However, it was necessary to develop an entirely new method for uniquely numbering closed-cage systems. This paper describes IUPAC recommendations for naming and uniquely numbering the two most common fullerenes with isolated pentagons, the icosahedral C60 fullerene and a D5h-C70 fullerene. It also describes recommendations for adapting organic nomenclature principles for naming fullerenes with nonclosed-cage structures, heterofullerenes, derivatives formed by substitution of hydrofullerenes, and the fusion of organic rings or ring systems to the fullerene cage. Finally, this paper suggests methods for describing structures consisting of two or more fullerene units and for denoting configurations of chiral fullerenes and their derivatives.

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31

Dolmatov, Valeriy K. y Steven T. Manson. "A Glimpse into Photodetachment Spectra of Giant and Nested Fullerene Anions". Atoms 10, n.º 4 (22 de septiembre de 2022): 99. http://dx.doi.org/10.3390/atoms10040099.

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We focus on the study of the photodetachment of bare, i.e., single-cage (CN)− as well as nested (multi-cage) (CN@CM@…)− singly charged fullerene anions. We calculate the attached electron’s wavefunctions, energies, oscillator strengths and photodetachment cross sections of the C60−, C240−, C540−, (C60@C240)−, (C60@C540)−, (C240@C540)− and (C60@C240@C540)− fullerene anions, where the attached electron is captured into the ground s-state by the resultant external field provided by all fullerene cages in the anion. The goal is to gain insight into the changes in behavior ofphotodetachment of this valence electron as a function of the different geometries and potentials of the various underlying fullerenes or nested fullerenes (fullerene onions) both due to their increasing size and due to “stuffing” of a larger bare fullerene with smaller fullerenes. To meet this goal, we opt for a simple semi-empirical approximation to this problem: we approximate each individual fullerene cage by a rigid potential sphere of a certain inner radius, thickness and potential depth, as in numerous other model studies performed to date. The results reveal a number of rather significant differences in the wavefunctions, oscillator strengths and photodetachment cross sections among these fullerene anions, some of which are completely counter-intuitive. The results obtained can serve as a “zeroth-order-touchstone” for future studies of single-cage and nested fullerene anions by more rigorous theories and/or experiments to build upon this work to assess the importance of interactions omitted in the present study.

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32

Wang, C. Z., B. L. Zhang, C. H. Xu, C. T. Chan y K. M. Ho. "STRUCTURES AND STABILITIES OF CARBON FULLERENES". International Journal of Modern Physics B 06, n.º 23n24 (diciembre de 1992): 3833–38. http://dx.doi.org/10.1142/s0217979292001894.

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The structures and stabilities of carbon fullerenes C n( n =20–94) are studied with tight-binding molecular dynamics in combination with a new scheme for generating energetically favorable fullerene networks. Magic numbers for fullerene formation energy are observed at n =60, 70 and 84. The experimental observation of the more abundant fullerenes is related to the fragmentation stabilities and chemical reactivities of the fullerenes obtained from our calculations.

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33

Jeon, Il, Han-Young Woo, Kyusun Kim y Ziang Wu. "(Digital Presentation) Homogeneously Miscible Fullerene Inducing Vertical Gradient in Perovskite Thin-Film Towards Highly Efficient Solar Cells". ECS Meeting Abstracts MA2022-01, n.º 1 (7 de julio de 2022): 140. http://dx.doi.org/10.1149/ma2022-011140mtgabs.

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Fullerene-based n-type charge-collecting materials have emerged as a solution to high-performance perovskite solar cells. However, their application to perovskite solar cells was limited in the device architecture and only a small amount of fullerene additives could be introduced to the device system, because of the immiscibility of the fullerene species with polar solvents. To overcome this, triethylene glycol monomethyl ether chain-attached fullerene derivatives are synthesized and applied to normal-type perovskite solar cells. The newly synthesized fullerenes exhibit excellent solubility in polar solvents. A novel approach to introducing miscible fullerenes into perovskite devices and inducing a favorable vertical gradient is proposed. Forming an overcoat on an electron-transporting layer and waiting for a few minutes, the fullerene derivatives progressively permeate into the fullerene-doped perovskite active film. By fabricating perovskite solar cells combining direct mixing, overcoating and waiting techniques, a remarkably high device efficiency of 23.34% is achieved. The high performance is attributed to the fullerene additives with a vertical gradient passivating the perovskite defect sites effectively and the overcoat enhancing the charge transfer. The device performance is certified by a national laboratory, which is the highest efficiency among the fullerene additives-used perovskite solar cells.

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34

Xu, Piao-Yang, Xiao-Qing Li, Wei-Guang Chen, Lin-Long Deng, Yuan-Zhi Tan, Qianyan Zhang, Su-Yuan Xie y Lan-Sun Zheng. "Progress in Antiviral Fullerene Research". Nanomaterials 12, n.º 15 (24 de julio de 2022): 2547. http://dx.doi.org/10.3390/nano12152547.

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Unlike traditional small molecule drugs, fullerene is an all-carbon nanomolecule with a spherical cage structure. Fullerene exhibits high levels of antiviral activity, inhibiting virus replication in vitro and in vivo. In this review, we systematically summarize the latest research regarding the different types of fullerenes investigated in antiviral studies. We discuss the unique structural advantage of fullerenes, present diverse modification strategies based on the addition of various functional groups, assess the effect of structural differences on antiviral activity, and describe the possible antiviral mechanism. Finally, we discuss the prospective development of fullerenes as antiviral drugs.

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35

Barrera, E. V., J. Sims, D. L. Callahan, V. Provenzano, J. Milliken y R. L. Holtz. "Processing of fullerene-reinforced composites". Journal of Materials Research 9, n.º 10 (octubre de 1994): 2662–69. http://dx.doi.org/10.1557/jmr.1994.2662.

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This work has been motivated by the current interest in using fullerenes as a possible reinforcement in structural materials. The fullerenes (of which C60 is the most common) are nanometer in size and have been observed to be stable in contact with various metal systems. Therefore, they offer a nanosize reinforcement that is lightweight and hollow. In this research the emphasis was on processing metals with fullerene additions where the fullerenes were dispersed throughout the metal. Various processing approaches were employed to produce nanocrystalline materials, thin films, and powder-processed composites. Indications are that fullerenes remained unaltered with each processing approach in matrices of tin, copper, and aluminum. A key aspect of the processing of metals containing dispersed fullerenes was the use of fullerene sublimation. Along with the various processing methods identified, the methods of characterizing the fullerenes in the metals were also identified.

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36

Ma, Yue y Yoko Yamakoshi. "(Invited, Digital Presentation) Aggregation Switchable Fullerene-Peptides Conjugates". ECS Meeting Abstracts MA2022-01, n.º 11 (7 de julio de 2022): 810. http://dx.doi.org/10.1149/ma2022-0111810mtgabs.

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Intensive research has been applied on chemical functionalization of fullerenes over the past decades, aiming at utilizing their broad availabilities in chemical biology field. Chemical moieties was induced to improve their water solubility and thus enhance their properties or interaction with biomolecules. In our previous study, we reported the synthesis of fullerene-PEG conjugates and demonstrated their ability for photoinduced DNA damage and ROS generation under visible light irradiation. In this work, we report a water-soluble fullerene derivative by constructing a fullerene-peptide conjugates. The aggregation behavior as well as bio properties has been systematically studied for this series of fullerene-peptide conjugates (Figure 1a). By altering the attached peptides, fullerenes could exist as monomer or micelle in aqueous phase (Figure 1b). Figure 1

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37

Farmanzade, Davood y Leila Tabari. "Characterization of the fullerene end-functionalized ZnO nanotube: A computational study". Journal of Theoretical and Computational Chemistry 15, n.º 04 (junio de 2016): 1650031. http://dx.doi.org/10.1142/s0219633616500310.

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The electronic and field emission properties of the fullerene end-functionalized zinc oxide nanotube (ZnONT) are investigated by density functional theory (DFT) to search for novel field emitter nano material. The interaction energies of ZnONT/fullerenes complexes gradually increase, with increasing the nanotube lengths which indicate that ZnONTs with higher lengths could improve the stability of the complexes. The band gaps of connected construction of fullerene molecules with ZnONTs gradually reduced by increasing the tube length, but were not sensitive to the tubes diameter. It is found that the ionization potentials of ZnONT/fullerenes complexes mainly decrease compared to that of pristine nanotube in the presence of 0, 0.002, 0.004[Formula: see text]a.u. electric field. The reduction of the ionization potential means the enhancement of the field emission properties of ZnONT/fullerenes complexes compared with simple ZnONT and fullerene molecules. The calculations show that the combination of ZnONT with fullerene molecules indeed improves the field emission by controlling the tube size and electric field strength.

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38

Fazylov, S. D., О. А. Nurkenov, Z. M. Muldakhmetov, A. M. Gazaliev, А. Е. Аrinova, M. K. Ibraev, L. M. Vlasova y A. S. Fazylov. "Biologically active derivatives of fullerene C60. Current state and development prospects". Bulletin of the Karaganda University. "Chemistry" series 99, n.º 3 (30 de septiembre de 2020): 11–20. http://dx.doi.org/10.31489/2020ch3/11-20.

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The article presents literature review on the physicochemical and biological properties of fullerene C60, as well as the authors' own experimental data on the synthesis of fullerene derivatives of amines and natural alkaloids. It is shown that the presence of a fullerene fragment in the structure of the compound provides a significant improvement or the appearance of qualitatively new mechanical, chemical, physical, biological and other properties associated with the manifestation of nanoscale factors. The issues of the relationship of the structure, water solubility and biological activity of fullerene С60 derivatives are considered. Many biologically active effects of various modified derivatives of fullerene C60 are described, which have membrane-active, antibacterial, antiviral, immunomodulating, HIV inhibitory enzymes and other properties. It was noted that preparations containing a fullerene fragment are effective against hepatitis C virus, and are also able to efficiently trap free radicals. Derivatives of fullerenes can also be used as antioxidant, neuroprotective and other agents. Particular attention is paid to the authors' own results on the synthesis of amino derivatives of fullerenes.

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39

Silant'ev A. V. "Energy Spectrum and Optical Absorption Spectrum of exohedral Fullerene C-=SUB=-50-=/SUB=-Cl-=SUB=-10-=/SUB=- within the Hubbard Model". Physics of the Solid State 64, n.º 6 (2022): 750. http://dx.doi.org/10.21883/pss.2022.06.53843.290.

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Energy spectra of fullerene C50 and exohedral fullerene C50Cl10 with the D5h symmetry groups have been obtained within the Hubbard model and static fluctuation approximation. The energy states have been classified using the methods of group theory, and the allowed transitions in the energy spectra of molecules C50 and C50Cl10 have been determined. On the basis of the energy spectrum of exohedral fullerene C50Cl10 is given an interpretation of experimentally observed optical absorption bands molecule C50Cl10. Keywords: Hubbard model, Green's functions, energy spectrum, fullerenes, nanosystems, fullerene C50, exohedral fullerene C50Cl10.

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40

Djordjevic, Aleksandar y Gordana Bogdanovic. "Fullerenol: A new nanopharmaceutic?" Archive of Oncology 16, n.º 3-4 (2008): 42–45. http://dx.doi.org/10.2298/aoo0804042d.

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Chemical modification of fullerenes to hydrosoluble cluster molecules made fullerenes interesting for biological investigation. Among them, polycarbonated and polyhydroxylated fullerene C60 derivatives showed the most interesting biological activities. In this paper, we present the most important recent results of in vitro and in vivo biological studies with fullerenol C60(OH)24. Fullerenol C60(OH)24 was strong antioxidant: it reacted with superoxide anion radical, hydroxy radical and nitrous oxide radical in chemical and biological systems. Fullerenol C60(OH)24 did not inhibit human breast cancer cell growth at concentrations from 0.8 to 3.45 ?M, but strongly modulated cytotoxic effects of doxorubicin and cis-platinum after 24 and 48 hours of treatment. Radioprotective effects of fullerenol C60(OH)24 were shown in different in vitro and in vivo models. Fullerenol C60(OH)24 (100 mg/kg) protected rat heart from doxorubicin toxicity. Biodistribution studies of fulelrenol were also investigated. Accumulating data from the literature and from our studies suggest that fullerenol, as a nanoparticle might be a new promising pharmaceutical in the near future.

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41

Gao, Yang y Heping Zhang. "Clar Structure and Fries Set of Fullerenes and (4,6)-Fullerenes on Surfaces". Journal of Applied Mathematics 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/196792.

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Fowler and Pisanski showed that the Fries number for a fullerene on surface Σ is bounded above by|V|/3, and fullerenes which attain this bound are exactly the class of leapfrog fullerenes on surface Σ. We showed that the Clar number of a fullerene on surface Σ is bounded above by(|V|/6)-χ(Σ), whereχ(Σ)stands for the Euler characteristic of Σ. By establishing a relation between the extremal fullerenes and the extremal (4,6)-fullerenes on the sphere, Hartung characterized the fullerenes on the sphereS0for which Clar numbers attain(|V|/6)-χ(S0). We prove that, for a (4,6)-fullerene on surface Σ, its Clar number is bounded above by(|V|/6)+χ(Σ)and its Fries number is bounded above by(|V|/3)+χ(Σ), and we characterize the (4,6)-fullerenes on surface Σ attaining these two bounds in terms of perfect Clar structure. Moreover, we characterize the fullerenes on the projective planeN1for which Clar numbers attain(|V|/6)-χ(N1)in Hartung’s method.

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42

Ma, Yue, Lorenzo Persi y Yoko Yamakoshi. "(Invited) Reactive Oxygen Generation from Photoexcited Fullerene-Peptide Conjugates". ECS Meeting Abstracts MA2023-01, n.º 12 (28 de agosto de 2023): 1265. http://dx.doi.org/10.1149/ma2023-01121265mtgabs.

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Fullerenes have been considered as excellent candidates for photosensitizers (PSs) in photodynamic therapy (PDT). Fullerenes are reported to generate reactive oxygen species (ROSs), through energy transfer (singlet oxygen 1O2, Type II reaction) and electron transfer (reduced active oxygen radicals such as superoxide anion radical O2-• and hydroxyl radical •OH, Type I reaction) in an effective way (Figure 1a).1,2 In our previous study, we reported the synthesis of fullerene-PEG conjugates and demonstrated their ability for photoinduced DNA damage and ROS generation upon visible light irradiation.2 In this work, we report the synthesis of a highly water-soluble fullerene-peptide conjugate. The fullerene-peptide conjugates are well-dispersed in aqueous media in comparation to fullerene-PEG conjugates, as indicated by dynamic light scattering (DLS) measurement as well as cryo-TEM microscopy. The ROSs generation capacity of fullerene-peptide conjugate, detected by electron paramagnetic resonance (EPR), DNA damage and in vitro photocytotoxicity tests will also be presented. Figure 1

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43

Alshehri, Mansoor H. "An Analytical Model for Lithium Storage in Spherical Fullerenes". Energies 15, n.º 19 (28 de septiembre de 2022): 7154. http://dx.doi.org/10.3390/en15197154.

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In this paper, the encapsulation of lithium atoms in spherical fullerenes of varying sizes is investigated. The 6–12 Lennard–Jones potential function and the continuum approximation, in which it is assumed that the atoms can be replaced with a uniform distribution across the surface of the molecules, are exploited to model the interaction energies between lithium atoms and spherical fullerenes. Thus, the total interaction energies can be approximated by applying surface integrations. The results show that for a lithium atom interacting inside a spherical fullerene, the interaction energies are minimized at a position that approaches the fullerene wall as the size of the fullerene increases. However, the results show that an external force would need to be applied to a lithium atom in order to overcome the repulsive energy barrier so that it can be encapsulated in CN fullerenes with a radius of less than 2 Å. The present study indicates that the optimal radius that gives the minimum energy for the storage of Li inside CN fullerenes occurs for a fullerene with a radius of ≈2.4 Å. Overall, this study provides an analytical formulation that may facilitate rapid computational results, and an application of this work is in the design of future high-energy-density batteries that utilize CN fullerenes.

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44

Tanuma, Yuri, Toru Maekawa y Chris Ewels. "Methodological Investigation for Hydrogen Addition to Small Cage Carbon Fullerenes". Crystals 11, n.º 11 (1 de noviembre de 2021): 1334. http://dx.doi.org/10.3390/cryst11111334.

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Hydrogenated small fullerenes (Cn, n < 60) are of interest as potential astrochemical species, and as intermediates in hydrogen-catalysed fullerene growth. However, the computational identification of key stable species is difficult due to the vast configurationally space of structures. In this study, we explored routes to predict stable hydrogenated small fullerenes. We showed that neither local fullerene geometry nor local electronic structure analysis was able to correctly predict subsequent low-energy hydrogenation sites, and sequential stable addition searches also sometimes failed to identify most stable hydrogenated fullerene isomers. Of the empirical and semi-empirical methods tested, GFN2-xTB consistently gave highly accurate energy correlations (r > 0.99) to full DFT-LDA calculations at a fraction of the computational cost. This allowed identification of the most stable hydrogenated fullerenes up to 4H for four fullerenes, namely two isomers of C28 and C40, via “brute force” systematic testing of all symmetry-inequivalent combinations. The approach shows promise for wider systematic studies of smaller hydrogenated fullerenes.

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45

Sánchez-Bernabe, Francisco J. "Study of fullerenes C₁₂₆ and C₁₅₆ with seven heptagon rings". Journal of Physics: Conference Series 2321, n.º 1 (1 de agosto de 2022): 012028. http://dx.doi.org/10.1088/1742-6596/2321/1/012028.

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Abstract We consider fullerenes C126 and C156, both of them with seven heptagon rings. The first of them is C126 with 19 pentagons, and 39 hexagons. It is also considered C156 with 19 pentagons, and 54 hexagons. From previous work, a couple of fullerenes, C130 and C134, are mentioned for comparative reasons. These two fullerenes also contain seven heptagon rings. Fullerene C130 is constituted of 19 pentagons, and 41 hexagons. On the other hand, fullerene C134 has 19 pentagons, and 43 hexagons. Therefore, the four fullerenes considered, with seven heptagon rings, also share the property that, the number of pentagons in each of them, is 19. This fact is a consequence of a couple of equations that relates the number of pentagons, hexagons, and heptagons contained in a fullerene. Classical fullerenes contain only pentagons and hexagons, and the more familiar example is C60 with 20 hexagons, and 12 pentagons. Actually, all classical fullerenes have 12 pentagons, regardless of how many hexagons are involved. Besides this type of molecules, there exists nonclassical fullerenes, where another type of ring is presented, like squares, or heptagons. In this paper, fullerenes with 126, 130, 134, and 156 carbons are considered, with seven heptagons, and as a consequence, all them contain 19 pentagons, and they have 39, 41, 43, and 54 hexagons, respectively. Future work would focus on finding fullerenes with a different number of carbons, and hexagons, but with 7 heptagons, and 19 pentagons. Thus, fullerene C128 of this type, should contain 40 hexagons.

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Tanaka, Takeshi. "Experimental Trial of Fullerene Wheel Fabrication". Key Engineering Materials 389-390 (septiembre de 2008): 61–66. http://dx.doi.org/10.4028/www.scientific.net/kem.389-390.61.

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The purpose of this study is to fabricate a wheel using fullerenes with nano-scaled particles, and to investigate the polishing performance of fullerene wheel. A super smooth surface was formed on a silicon wafer by polishing the wafer with metal-bonded diamond wheels using a diamond abrasive grit of 0-0.125 μm and fullerenes with a diameter of 0.7 nm. We used two kinds of metal-bonded diamond wheels for pre-polishing and a metal-bonded fullerene wheel for the finishing process. Though the surface roughness after polishing with the fullerene wheel was almost equal to that obtained by polishing with the metal-bonded diamond wheel using diamond abrasive grit of 0-0.125 μm, the chemical-mechanical polishing process was clarified by AFM (atomic force microscope) observation when we used a metal-bonded fullerene wheel with 5wt% KOH (potassium hydroxide) solution. The greater number of smoothed portions on the surface of the silicon wafer indicated that the fullerenes provided the same polishing ability as that of the abrasive grit.

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Khamatgalimov, Ayrat R., Valeri I. Kovalenko y Anna S. Egorova. "Instability of molecular structure of non-IPR isomer 17984 (C1) of the C76 fullerene and probable ways of its stabilization". Butlerov Communications 63, n.º 9 (30 de septiembre de 2020): 1–9. http://dx.doi.org/10.37952/roi-jbc-01/20-63-9-1.

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It is well-known that non-IPR fullerenes are highly unstable. For this reason, they cannot be obtained as pristine fullerenes; however, some of them become stable as derivatives (exohedral or endohedral). In this article, we attempted to elucidate in detail molecular structure for such a non-IPR fullerene. Using theoretical approach supported by DFT calculations, the features of molecular structure of isomer 17894 (C1) of fullerene C76 with data about distribution of single, double and delocalized π-bonds as well its structural formula has been determined for the first time. The instability of the studied fullerene molecule caused by its open-shell structure and significant local overstrains related to the high folding angle value of pentagons in pentalene fragment. The supposed synthesis of the endohedral molecule starts with the ionic pair formation, i.e. anionic fragment of fullerene cage and metal cation electrostatically bound with it. It would lead to closing of open electron shell of fullerene and local overstrain release at pentalene fragment. As to the exohedral derivatives the probable positions of addends are discussed. Both methods in their own demonstrate the possibilities to stabilize the molecule of the C76 isomer 17894. The elucidation and analysis of structural features along with electronic characteristics of non-IPR fullerene molecules appear to be useful for predicting the possibility of their synthesis as derivatives and will assist in determination of their reactivity. This will ensure the targeted production of fullerenes and their derivatives for the needs of medicine, electronics and other industries. The fundamental knowledge of the properties of nanoobjects, namely fullerenes, is actually developing as the independent direction with a long-term perspective.

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Cruz-Silva, Rodolfo, Takumi Araki, Takuya Hayashi, Humberto Terrones, Mauricio Terrones y Morinobu Endo. "Fullerene and nanotube growth: new insights using first principles and molecular dynamics". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, n.º 2076 (13 de septiembre de 2016): 20150327. http://dx.doi.org/10.1098/rsta.2015.0327.

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Shortly after the discovery of fullerenes, many researchers pointed out that carbon nanotubes could be considered as elongated fullerenes. However, the detailed formation mechanism for both structures has been a topic of debate for several years, and consequently it has been difficult to draw a clear connection between the two systems. While the synthesis conditions appear to be different for both fullerenes and nanotubes, here, we demonstrate that it is highly likely that, at an initial growth stage, single-walled carbon nanotubes begin to grow from a hemisphere-like fullerene cap. More importantly, by analysing the minimum-energy path, it is shown that the insertion of C 2 fragments drives the transformation of this fullerene cap into an elongated structure that leads to the formation of very short carbon nanotubes. This article is part of the themed issue ‘Fullerenes: past, present and future, celebrating the 30th anniversary of Buckminster Fullerene’.

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Maharramova, M. Ya, I. S. Guliyev, A. B. Huseynov y E. B. Zeynalov. "Carbonic nanostructures in subsurface rocks: problem review Part I. Fullerenes". Azerbaijan Oil Industry, n.º 8 (15 de agosto de 2020): 4–13. http://dx.doi.org/10.37474/0365-8554/2020-8-4-13.

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The paper deals with the review of the results of detection and analysis of fullerenes in natural objects. The fullerenes (generally, buckminsterfullerenes С60) were revealed in hard subsurface rocks and sedimentary deposits of Cretaceous-Paleogene, Perm and Pre-Cambrian stages of the Earth. The map of the Earth regions of fullerene exploration and the data on fullerene composition in the rocks is provided as well. The concepts of both biogenic and abiogenic fullerene origin are known. In the first case, the process of slow metamorphization of putrid mud and terrestrial crop took place under the impact of compressing and temperature, as a result of which various allotrope compounds of hydrocarbon dispersed in the mineral matrix were formed and accumulated. In the second case, the formation of fullerenes took place due to the shocking impact during thunderbolt or fireballs (Sudbury meteorite, carbonic chondritic meteorites) strikes on the rocks of earth surface, as well as global forest fires. For reliable fullerene identification in the samples of sedimentary and subsurface rocks should be used only physical-chemical methods of high definitions, such as laser desorption / ionization and electric-shocking mass-spectrometry. In the natural objects is predominantly revealed fullerene С60.Other types of fullerenes - C70, C74, C78, C84 and C100 are identified more rarely. A hypothesis on the composition of carbonic nanostructures in the rocks of mud volcanoes in the aspect of obtained information is developed.

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Zimmerman, Paul A. y David M. Hercules. "Formation and Detection of Fullerene Metal Complexes Using Time-Of-Flight Secondary Ion Mass Spectrometry". Applied Spectroscopy 47, n.º 10 (octubre de 1993): 1545–47. http://dx.doi.org/10.1366/0003702934334651.

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We have found that metal/fullerene adduct ions of the C60 and C70 fullerenes can be formed with silver, gold, rhodium, and palladium by argon-ion bombardment of fullerenes deposited on a metal substrate, with the use of a Time-of-Flight Secondary Ion Mass Spectrometer (TOF-SIMS). The bis and tris metal/fullerene adducts formed include: Ag(C60)2+, AgC60C70+, Ag(C70)2+, Ag(C60)3+, Ag(C60)2C70+, AgC60(C70)2+, and Rh(C60)2+. In addition, the monomeric adducts AgC60+, AgC70+, AuC60+, AuC70+, RhC60+, RhC70+, and PdC60+ also have been detected. Samples prepared with a raw soot extract gave higher yields of metal/fullerene adducts in TOF-SIMS than those prepared with purified fullerenes. This result may indicate the presence of a matrix component in the raw soot which enhances the formation of fullerene metal adducts. Spectra obtained from the raw soot show peaks at every 24 daltons corresponding to even-numbered carbon clusters. These peaks occur as low as 600 daltons (C50) and as high as 3000 (C250).

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