Studies of fullerenes

Two other selected examples of the application of INADEQUATE to fullerenes focus on endohedral metallofullerenes. The first is based on the reported mapping of the bond connectivity in the carbon cage of La C82 anion, [La C82A]+75 The 13C NMR spectrum of [La C82A] showed 17 distinct lines of near-equal intensity and 7 lines of half the intensity. This is expected (17x4 + 2x7 = 82) for a molecule with a C2l. symmetry. 

The second example describes the determination of the position of the Ce atom in Ce C82 by means of paramagnetic NMR spectral analysis of the 13C signals of 

13C NMR spectrum of [Ce C82A] shows 24 lines and confirms the existence of C2Z7 symmetry. The spread of the resonances in this anion is, however, larger compared with the diamagnetic [La C82-A] in Ref. 75. All carbon chemical shifts 

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Meijer G and Bethune D S 1990 Laser deposition of oarbon olusters on surfaoes-a new approaoh to the study of fullerenes J. Chem. Rhys. 93 7800-2... 

Campbell E B and Hertel I V 1992 Molecular beam studies of fullerenes Carbon 8 1157-65... 

Bulhoes LOS, Obeng Y S and Bard A J 1993 Langmuir-Blodgett and electrochemical studies of fullerene films Chem. Mater. 5 110-14... 

Stasko A, Brezova V, Biskupie S, Dinse K-P, Sehweitzer P and Baumgarten M 1995 EPR study of fullerene radieals generated in photosensitized TiOg suspensions J. Phys. Chem. 99 8782-9... 

Cagle D W, Kennel S J, Mirzadeh S, Alford J M and Wilson L J 1999 In vivo studies of fullerene-based materials using endohedral metallofullerene radiotraoers Proc. Natl Acad. Sc/. USA 96 5182-7... 

Acknowledgements—This work was supported by the Office of Naval Research, the National Science Foundation, the Robert A. Welch Foundation, and used equipment designed for study of fullerene-encapsulated catalysts supported by the Department of Energy, Division of Chemical Sciences. 

A. Rojas-Aguilar./i/z Isoperibol Micro-bomb Combustion Calorimeterfor Measurement of the Enthalpy of Combustion. Application to the Study of Fullerene Cgo-J. Chem. Thermodynamics 2002, 34, 1729-1743. 

Wong-Ekkabut, J., Baoukina, S., Triampo, W., Tang, I.M., Tieleman, D.P., Monticelli, L. Computer simulation study of fullerene translocation through lipid membranes. Nat. Nanotechnol. 2008, 3, 363-8. 

Electrochemical studies of fullerene crown ether conjugates (38), (39), and (40) yielded fascinating results. The three compounds differ only in the points of attachment of the tangential crown... 

However, a photofragmentation study of fullerene positive ions (O Brien et al. 1988) provides some experimental evidence that ring rearrangements are reasonably facile. In these studies a positive ion was mass-selected, excited by an excimer laser, and the resulting fragment ions mass detected. Almost certainly these large ions... 

Zheng, G., Me, S., Elstner, M., Morokuma, K. (2004), Quantum Chemical Molecular Dynamics Model Study of Fullerene Formation from Open-Ended Carbon Nanotubes, J. Phys. Chem. A 108, 3182-3194. 

Since their discovery in 1985 [1] and subsequent isolation in macroscopic quantities [2], fullerenes and related forms of carbon such as nanotubes have been the subject of enormous numbers of both theoretical and experimental studies. This chapter describes a series of theoretical studies of fullerenes, concentrated on buckminsterfullerene, the original and still the most common form, which are tied together by an underlying valence bond picture of chemical structure. This work has attempted to identify characteristics of fullerenes which are more easily discerned in a valence bond than in a molecular orbital picture, and to see how far these valence bond ideas can be pushed before they break down. 

One semiempirical method which has been a workhorse in studies of fullerenes is the MNDO (Modified Neglect of Differential Overlap) method [4], which treats all valence electrons explicitly but within an essentially molecular... 

Rudalevige T., Francis A.H., and Zand R. (1998) Spectroscopic studies of fullerene aggregates, JPhys Chem A, 102, 9797-9802. 

Jaffe RL (2003) Quantum chemistry study of fullerene and carbon nanotube fluorination. J. Phys. Chem. B 107 10378-10388... 

In this review we focus both on major developments in new mass spectrometric techniques and on novel chemical applications of existing mass spectrometric techniques that have been reported since 1990. Emphasis is given to the application of these techniques to the study of bimolecular ion/molecule reactions, radiative association, and dissociative recombination of positive ions. Particular attention is given to the emerging field of interstellar metal-ion chemistry and recent studies of fullerene-ion chemistry and the influence of charge state on this, and related, chemistry. Mass spectrometric studies of the photochemistry of interstellar ions are briefly considered as is interstellar negative-ion chemistry. We conclude with a brief description of the use of mass spectrometry to examine interstellar material that has made the long journey to our solar system. 

Based on a study of fullerene solubility [1], it has been found that C6o fullerene, being a nonpolar molecule, is insoluble in polar solvents, such as alcohol, acetone, tetrahydrofurane etc. Relying on the above, it has been concluded that the solvation mechanism of dissolving plays an insignificant part in the processes of fiillerene dissolution. 

Figure 7.16 Bio-distrihution of Hox Cs2(OH)y in BALB/c mice at different timescales [169]. (Reprinted with permission from L.J. Wilson et al., In vivo studies of fullerene-hased materials using endohedral metallofullerene radiotracers, Proceedings of the National Academy of Sciences of the United States of America, 96, 5182-5187, 1999. 1999 National Academy of Sciences, U.S.A.).

Me90b G. Meijer and D. S. Bethune, Laser Depositions of Carbon Clusters on Surfaces A We89 New Approach to the Study of Fullerenes, ... 

H. W. Kroto and D. R. M. Walton, A Mass Spectrometric-NMR Study of Fullerene-78 Wa92 Isomers, J. Chem. Soc., Chem. Commun. 

Studies of fullerenes as adsorbents from an aqueous solution in relation with the removal of pollutants are relatively scarce. Thus, Berezkin et al. [100, 101] investigated the adsorptive activity of fullerenes for organic pollutants in water and compared them with activated carbon and soots with and without fullerenes. They studied the purification of natural river water and waste from a pharmaceutical plant. The latter liquid contained various aliphatic, cyclic and aromatic compounds, the overwhelming majority of organic impurities being chlorinated compounds. The adsorption behavior of soot was found to be similar... 

Irle S, Zheng G, Elstner M, Morokuma K (2003) Lormation of fuUerene molecules from carbon nanotubes a quantum chemical molecular dynamics study. Nano Lett 3(4) 465-470 Zheng G, Irle S, Elstner M, Morokuma K (2004) Quantum chemical molecular dynamics model study of fullerene formation from open-ended carbon nanotubes. J Phys Chem A 108 3182-3194... 

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