Fullerenes Cn Research Articles

Theoretical and Quantitative Structural Relationships Studies of Free Energies of Electron Transfer, Electron Transfer Kinetic, and Electrochemical Properties of Metal Nitride Cluster Fullerenes Y3N@C80Methano Mono Adduct Derivatives in [X-UT-V][Y3N@C80-[6,6]-Methanofullerene-R] (R = DEM, ex-TTF, and OCH2-AQ) Supramolecular Complexes

ABSTRACT Since the discovery of fullerenes as a class of nanostructure compounds, many potential applications have been suggested for their unusual structures and properties. The isolated pentagon rule (IPR) states that all pentagonal carbon rings are isolated in the most stable fullerene. Fullerenes Cn , are a class of spherical carbon allotrope group with unique properties. Electron transfer between fullerenes and other molecules is thought to involve the transfer of electrons between molecules surrounding the fullerene cage. One class of interesting molecules is the mono adduct methanofullerene derivatives (Y3N@C80-[6,6]-Methanofullerene-R). Electron transfer between C80 derivatives such as nitride Yttrium cluster Y3N@C80-[6,6]-Methanofullerene-R (R = DEM, exTTF, and OCH2-AQ) 10–12 and other molecules is thought to involve the transfer of electrons between molecules surrounding the fullerene cage. One class of electron-transfer molecules is the [X-UT-V][Y3N@C80-[6,6]-Methanofullerene-R] (R = DEM, exTTF...

Structural Relationships and Theoretical Study of Electron Transfer Properties of 1,3,2-Dithiazolyl Radicals with Fullerenes in Nanostructure [1,3,2-DTA(s)]@Cn Supramolecular Complexes

Various empty carbon fullerenes with different carbon atoms have been obtained and investigated. The dithiazolyl radicals have shown important electron-transfer properties. Topological indices are digital values that are assigned based on chemical composition. These values are purported to correlate chemical structures with various chemical and physical properties. They have been successfully used to construct effective and useful mathematical methods to establish clear relationships between structural data and the physical properties of these materials. In this study, the number of carbon atoms in the fullerenes was used as an index to establish a relationship between the structures of 2,3-naphthalene-1,3,2-dithiazolyl (NDTA), 2,3-quinoxaline-1,3,2-dithiazolyl (QDTA), and 1,2,5-thiazolo[3,4-b]-1,3,2-dithiazolo[3,4-b]pyridazin-2-yl (TDP-DTA), radicals, 1–3 as molecular conductor radicals and fullerenes Cn (n = 60, 70, 76, 82, and 86), which create [1,3,2-DTA(s)]@Cn, A-1 to A-5 (NDTA]@Cn), B-1 to B-5 ([QDTA]@Cn), and C-1 to C-5 ([TDP-DTA]@Cn). The relationship between the number of carbon atoms and the free energies of electron transfer (ΔGet(1) to ΔGet(4) ) are assessed using the Rehm–Weller equation for A-1 to A-5, B1 to B-5, and C-1 to C-5 supramolecular [1,3,2-DTA(s)]@Cn complexes. Calculations are presented for the four reduction potentials ( Red.E1 to Red.E4 ) of fullerenes Cn . The results were used to calculate the four free energies of electron transfer (ΔGet(1) to ΔGet(4) ) of supramolecular complexes A-1 to A-18, B-1 to B-18, and C-1 to C-18 (5–60) for fullerenes C60 to C300.

Theoretical Study of Structural Relationships and Electrochemical Properties of Supramolecular [14-MR Macrolides]@Cn Complexes

Macrolides are a broad spectrum of antibiotics that are commonly used in human pathologies as well as in veterinary medicine. The electrochemical detection of macrolide antibiotics were studied at various methods using amperometric and coulometric detectors. Since the discovery of fullerenes (Cn), one of the main classes of carbon compounds, the unusual structures and physiochemical properties of these molecules have been discovered, and many potential applications and physicochemical properties have been introduced. Up to now, various empty carbon fullerenes with different numbers “n,” such as C60, C70, C76, C82, and C86, have been obtained. Topological indices are digital values that are assigned based on chemical composition. These values are purported to correlate chemical structures with various chemical and physical properties. They have been successfully used to construct effective and useful mathematical methods to establish clear relationships between structural data and the physical properties of these materials. In this study, the number of carbon atoms in the fullerenes was used as an index to establish a relationship between the structures of Erythromycin-A (EA), Erythromycin-A enol ether (EMEN), Olendomycin (OM), and Anhydroerythromycin-A (AEA), 1-4 and fullerenes Cn (n = 60, 70, 76, 82 and 86), which create [Tetracyclines]@Cn, A-1 to A-5 ([EA]@Cn), B-1 to B-5 ([EMEN]@Cn), C-1 to C-5 ([OM]@Cn), and D-1 to D-5 ([AEA]@Cn). The relationship between the number of carbon atoms and the free energies of electron transfer (ΔGet(1) to ΔGet(4)) is assessed using the Rehm-Weller equation for A-1 to A-5, B1 to B-5, C-1 to C-5, and D-1 to D-5 supramolecular [14-MR Macrolides]@Cn complexes 5-24. Calculations are presented for the four reduction potentials (Red.E1 to Red.E4) of fullerenes C n . The results were used to calculate the four free-energies of electron transfer (ΔGet(1) to ΔGet(4)) of supramolecular complexes A-1 to A-18 to B-1 to B-18, C-1 to C-18, and D-1 to D-18 (5-76) for fullerenes C60 to C300.

Theoretical Study of Structural Relationships and Electrochemical Properties of Supramolecular [Tetracyclines].Cn Complexes

Tetracyclines are a broad spectrum of antibiotics that are commonly used in human pathologies as well as in veterinary medicine as animal nutrition and feed additives for cattle growth. The electrochemical oxidation of the tetracycline antibiotics was studied at various carbon electrodes including glassy carbon (GC), as deposited BDD (boron‐doped diamond thin film) and anodized BDD electrodes using cyclic voltammetry. Since the discovery of fullerenes (Cn), one of the main classes of carbon compounds, the unusual structures and physiochemical properties of these molecules have been discovered, and many potential applications and physicochemical properties have been introduced. Up to now, various empty carbon fullerenes with different numbers “n,” such as C60, C70, C76, C82 and C86, have been obtained. Topological indices are digital values that are assigned based on chemical composition. These values are purported to correlate chemical structures with various chemical and physical properties. They have been successfully used to construct effective and useful mathematical methods to establish clear relationships between structural data and the physical properties of these materials. In this study, the number of carbon atoms in the fullerenes was used as an index to establish a relationship between the structures of Tetracycline (TC), Chlortetracycline (CTC), Doxytetracycline (DTC) and Oxyteracycline (OTC), 1–4 and fullerenes Cn (n = 60, 70, 76, 82 and 86), which create [Tetracyclines].Cn, A‐1 to A‐5 ([TC].Cn), B‐1 to B‐5 ([CTC].Cn), C‐1 to C‐5 ([DTC].Cn) and D‐1 to D‐5 ([OTC].Cn). The relationship between the number of carbon atoms and the free energies of electron transfer (ΔGet(1) to ΔGet(4) ) are assessed using the Rehm‐Weller equation for A‐1 to A‐5, B1 to B‐5, C‐1 to C‐5 and D‐1 to D‐5 supramolecular [Tetracyclines].Cn complexes 5–24. Calculations are presented for the four reduction potentials ( Red.E1 to Red.E4 ) of fullerenes Cn . The results were used to calculate the four free‐energies of electron transfer (ΔGet(1) to ΔGet(4) ) of supramolecular complexes A‐1 to A‐19 to B‐1 to B‐19, C‐1 to C‐19 and D‐1 to D‐19 (5–81) for fullerenes C60 to C300.

Assemblies of carbon and boron-nitrogen nanotubes and fullerenes: Structure and properties

This review concerns assemblies of the main carbon nanostructures (fullerenes and nanotubes) generated by interactions between similar and dissimilar species. The two major families of these nanomaterials are reviewed: (1) assemblies with weak (van der Waals) bonds between fullerenes and/or nanotubes (fullerites, nanopeapods, nanotube bundles, and nanotubular crystals) and (2) assemblies formed by covalently bonded (polymerized) fullerenes and/or nanotubes (covalent crystals of small fullerenes C n < 60 , nanobuds, ropes of polymerized nanotubes, and covalent networks built of nanotubes). Data are systematized on their atomic structures, stability factors, electronic structures, chemical bonding, physical and chemical properties, and potential fields of application. Related heteronanomaterials (assemblies of boron-nitrogen fullerene-like molecules and/or nanotubes) are reviewed briefly.

Polythermal solubility of light fullerenes in valeric and caproic acids in the temperature range 20–80°C

The polythermal solubility of fullerene C60 and a fullerene mixture (60 wt % C60 + 39 wt % C70 + 1 wt % higher fullerenes Cn, n = 76, 78, 84, 90...) in valeric and caproic acids was studied in the temperature range 20–80°C. The solubility diagrams are presented and characterized.

Charged Fullerenes as High-Capacity Hydrogen Storage Media

Using first-principles calculations within density functional theory, we explore systematically the capacity of charged carbon fullerenes Cn (20 <or= n <or= 82) as hydrogen storage media. We find that the binding strength of molecular hydrogen on either positively or negatively charged fullerenes can be dramatically enhanced to 0.18-0.32 eV, a desirable range for potential room-temperature, near ambient applications. The enhanced binding is delocalized in nature, surrounding the whole surface of a charged fullerene, and is attributed to the polarization of the hydrogen molecules by the high electric field generated near the surface of the charged fullerene. At full hydrogen coverage, these charged fullerenes can gain storage capacities of up to approximately 8.0 wt %. We also find that, contrary to intuitive expectation, fullerenes containing encapsulated metal atoms only exhibit negligible enhancement in the hydrogen binding strength, because the charge donated by the metal atoms is primarily confined inside the fullerene cages. These predictions may prove to be instrumental in searching for a new class of high-capacity hydrogen storage media.

Properties of Non-Conventional Fullerenes (Cn; 48< n < 60) Prepared by Soft-Landing Ion Deposition

not Available.

Ionization Energy of Fullerenes

Ionization energies of the higher fullerenes Cn (n = 70−106) were measured by means of the ion-molecular equilibria−Knudsen cell mass spectrometry method. The obtained values were found to decrease with the size, going from IE(C70) = 7.36 eV down to IE(C106) = 6.92 eV, with unexpectedly low IE(C74) = 7.13 eV. A good correlation of the experimental results with the theoretical values is demonstrated. A simple model describing the ionization properties dependence from the fullerene size is proposed.

Valence bond multiple excitation RVB calculations on the singlet ground states of some carbon fullerenes Cn with 20⩽n⩽60

A detailed analysis of the nature of the π-VB singlet ground state in terms of multiply excited resonance valence bond (RVB) wavefunctions is presented for some carbon fullerenes in the range from 20 to 60 atoms by comparison to exact solutions of the Heisenberg model for fullerenes of up to 30 atoms. It is found that singlet pair excitations over an odd number of bonds are more important than those over even ones. By far the most important contributions to the ground-state energies besides the non-excited Kekulé RVB space come from those RVB functions containing singlet pair excitations over three carbon bonds.

Properties of Boron-Substituted Heterofullerenes

On the basis of a succinct description of geometrical configurations for giant fullerenes, the electronic properties and structural distortions of heterofullerenes CN-1B(N = 60, 180, 240, 420, 540, 720, 780) are analyzed by the extended Su-Schrieffer-Heeger model. In comparison with their pristine fullerenes CN, local distortions and mid-gap states are found to occur in boron-doped giant fullerenes.

C 60, C 60O, C 70 and C 70O fullerene formations in premixed benzene-oxygen flames

The use of hydrocarbons for fullerenes synthesis has been described in the literature. In this study, the formation of fullerenes C60, C60O, C70, and C70O is investigated in premixed benzene-oxygen flames operated under a pressure of 7.5 kPa by systematically varying two physicochemical parameters: the initial velocity of the fresh gas mixture (at 298 K) at the burner, which is varied between 40 and 50 cm s−1, and the atomic C/O ratio, which is varied from 0.7 to 1.15. The objective of running each flame at different sets of conditions is to assess the sensitivity of reaching an optimum in the process of fullerenes production in flames. A higher production rate of fullerenes Cn under different conditions is achieved at an optimal level of C/O ratio of 1.05 and 45 cm s−1 of gas velocity. In addition, the highest production rate of fullerenes is 786.7 mg/h, and the highest yield of carbon transformed to fullerenes, obtained is 0.22%. Flame synthesis of fullerenes would seem to offer potential for large-scale production. Different patterns for the production of fullerene and fullerenes oxide are obtained. This result seems to challenge the notion of complexity of the combustion, which accompanies the formation of these carbon molecules in flames. The mass spectrometer shows that heavy fullerenes containing more than 150 atoms are present in the production process. Peaks of PAH at m/e smaller than 500 amu suggest that the reaction of combining the polycyclic aromatic hydrocarbons in burned gases may play an important role in the formation of fullerenes in burned gas flames.

Electronic Properties of Fullerenes

Systematic investigation of the electronic properties of fullerenes CN (N =60, 70, 76, 78, 82, 84, 86) has been made by cyclic voltammetry, optical absorption, and photo-ionization measurements. The HOMO-LUMO gap decreases monotonically with increase of number of carbon atoms (N) and shows a characteristic 1/Ndependence comparing with those of polyenes and aromatic hydrocarbons. As a reflection of large molecular size, the Coulombrepulsive energy,U′, is considerably small less than 0.4 eV and decreases further with increase of molecular size.

Electronic structure of icosahedral fullerenes

In this article, a new method was proposed to solve the Hückel Hamiltonian of any fullerene with a certain point group as its symmetry. This method was applied to calculate the π energy levels of icosahedral fullerenes Cn (Ih, n = 60h2, 25 ≥ h > 0), Cn (Ih, n = 20h2, 39 ≥ h > 0), and Cn (I, n = 20(h2 + hk + k2), 20 − k ≥ h > k > 0), where h and k are two integers. From the calculated results, certain general rules were obtained for the stability and chemical reactivity of icosahedral fullerenes. © 1997 John Wiley & Sons, Inc.

On the Size Dependence of Standing Waves in Tubular Fullerenes

Summary We present an analysis of principal vibrational modes whose propagation creates the standing waves along the lateral surfaces of the elongated fullerenes. We deduce the recurrence rules determining the possibility of resonances between the skew and vertical modes, as well as the appearance of isolated standing waves with nodes in the elongated fullerenes CN with N = 50 + 10k, k= 1,2,3…. We discuss briefly the influence of different vibrational spectra on the mechanical stability of CN-elongated fullerenes, and its impact on the relative rate of their production. This work has been partly supported by the joint French-German Research Programme “PROCOPE”.

On the Limitation of Net Algorithm for Enumerating Isomeric Structures of Giant Fullerenes

Abstract Application of our net algorithm to the generation of all possible IPR isomers for giant fullerenes Cn, n=102 to 120, missed nine out of 39,621 possible structures. Analysis revealed that the omission of too small and too large cap triangles was the reason. Within the range of fullerenes studied, the missed structures are of high-energy and do not affect the distribution of significantly low-energy isomers.

Electronic structures of fullerenes Cn with Ih symmetry and n=20k2.

There are two classes of fullerenes with {ital I}{sub {ital h}} symmetry, one with {ital n}=60{ital k}{sup 2} and the other with {ital n}=20{ital k}{sup 2}, where {ital n} is the number of carbon atoms and {ital k} is any positive integer. Actually, the second class {ital n}=20{ital k}{sup 2} can be further divided into three types: {ital n}=20(3{ital m}+1){sup 2}, {ital n}=20(3{ital m}+2){sup 2}, and {ital n}=20(3{ital m}+3){sup 2}, where {ital m} is any non-negative integer. We have proposed a method for H{umlt u}ckel theory calculations that is based on combining the topology of fullerenes and the irreducible representation matrices as the elements of the secular equations. The method has been used to calculate the electronic structures of fullerenes C{sub {ital n}} ({ital I}{sub {ital h}}, {ital n}=60{ital k}{sup 2}) with the values of {ital k} from 1, 2, up to 25 in our previous papers. In this article this method has been further extended with some computational alterations to calculate the {pi} electronic energy levels of fullerenes C{sub {ital n}} [{ital I}{sub {ital h}}, {ital n}=20(3{ital m}+1){sup 2}, {ital n}=20(3{ital m}+2){sup 2}, and {ital n}=20(3{ital m}+3){sup 2}] with the values of {ital m} from 0, 1 up tomore » 12. From the calculated results of the 39 fullerene molecules certain general rules on the stability and chemical reactivity have been drawn for the three types of fullerenes. {copyright} {ital 1996 The American Physical Society.}« less

フラーレン（Ｃ６０類）研究の展開とその興味

The science of fullerene, after the discovery of its synthesis and seperation processes, have been developing quite rapidly. This review surveys the basic trend of its progress especially from the materials science view points and future aspects are discussed. In addition to C60, the higher fullerenes Cn (n≥70) and metal doped fullerene Mm@C82 are also included. Discussion is made on fullerene related materials such as carbon nanotubes and nanocapsules.

Delayed electron emission from higher fullerenes Cn, n .ltoreq. 96, following excitation at 1064 nm

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDelayed electron emission from higher fullerenes Cn, n .ltoreq. 96, following excitation at 1064 nmKeith W. Kennedy and Olof EchtCite this: J. Phys. Chem. 1993, 97, 27, 7088–7091Publication Date (Print):July 1, 1993Publication History Published online1 May 2002Published inissue 1 July 1993https://doi.org/10.1021/j100129a027RIGHTS & PERMISSIONSArticle Views60Altmetric-Citations18LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (504 KB) Get e-Alerts

巨大フラーレンの構造の位相幾何学的考察

The structures of giant fullerenes have been considered from the topological view point. As the fullerenes are formed of the pentagonal rings and hexagonal rings, Euler's theorem in the topology shows that 12 pentagonal rings are neccessary though the number of hexagonal ones is arbitrary for the formation of the closed polyhedron. This restraint predicts that symmetric giant fullerenes have the following shapes: the icosahedral-shaped, the tetrahedral-shaped, the pentagonal prism-shaped and the hexagonal prism-shaped ones. We have classified the icosahedral-shaped and the tetrahedral-shaped ones into three systems, respectively, and the pentagonal prism-shaped and the hexagonal prism-shaped ones into two systems, respectively, thus totaling ten systems. We have formulated the equations for calculating the number of atoms n in the giant fullerenes Cn. The results indicate that the forming of the round-shaped giant fullerenes requires the sets of heptagonal and pentagonal rings while keeping (the number of pentagonal rings)-(the number of heptagonal rings)=12.