Article

Capturing the Labile Fullerene[50] as C50Cl10

State Key Laboratory for Physical Chemistry of Solid Surfaces and Department of Chemistry, Xiamen University, Xiamen, 361005, China.
Science (Impact Factor: 33.61). 05/2004; 304(5671):699. DOI: 10.1126/science.1095567
Source: PubMed
Download full-text

Full-text

Available from: Xin Lu
  • Source
    • "Carbon maximum pentagon separation [23e25] and maximum aromaticity [26] [27] rules have been formulated for the rapid selection of lower-energy isomers for fullerenes or charged fullerenes. However, unlike fullerenes or EMFs, the large-scale syntheses of MMAs are mainly based on purified EMFs at relatively low temperatures (<200 C) [28e30], although the annealing of chlorinedoped carbon plasma at high temperatures also yields polychlorinated fullerenes [31] [32]. This means the energy-based rules for fullerenes and EMFs, which are rooted in the low-energy criterion [16e25], are not suited to MMAs that are of current interest in applications. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Metallofullerene multiple adducts (MMAs) have properties inherited from fullerene cores and new properties from exohedral chemical groups. However, the huge structural varieties of MMAs hinder their separation, purification and characterization. Here, we report that only subsets with large first excitation energies (FEEs) are chemically stable and likely to survive experimentally. On the basis of quantum confinement effect, we propose and verify a simple rule of thumb to quickly predict whether MMAs have large FEEs: only those whose sp2-carbons form aromatic patches isolated by sp3-carbons have large FEEs. It can serve as a tool for rapid screening of MMAs with high chemical stabilities. The rule involves the concept of forming anionic aromatic patches containing metals, which further provides an explicit physical picture on the metal-cage interaction within metallofullerenes. The results present here will not only benefit the future study of MMAs but also provide insights into the fundamental chemistry of metallofullerenes.
    Full-text · Article · Jan 2016 · Carbon
  • Source
    • "A desirable way to reduce the reactivity and increase the stability of small fullerenes was to saturate each double bond by hydrogenation [2]. Recently, it has been reported that small fullerenes could be synthesized by the methods of covalently bonded assembly derivation and hydrogen (or chlorine) termination [3] [4] [5] [6], which meant that small fullerenes can be stabilized and synthesized through an optimized strategy in experiment. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Small carbon nanocrystal particle (C20, C24, C26) series, synthesized in an ultrahigh molecular weight polyethylene target by C2 + ion beam irradiation, were studied with respect to their micro structures and sequential growth features. As the samples were examined by laser desorption Time-of-flight mass spectroscopy, relative intensive peaks in the spectrum indicated the presence of C20, C24, C26 carbon clusters. High resolution transmission electron microscopy images and electron diffraction patterns showed that the C20, C24 and C26 assembled into nanocrystal particles. Raman scattering spectrum and Fourier transform infrared spectrum analyses also indicated that the active bonds of small carbon cages were hydrogenated, thus the C20, C24, C26 nanocrystal were formed. Additionally, the sequential growth of C20→C22→C24→C26→...with addition of C2 carbon units was found, which provides a novel and efficient approach to synthesize small hydro-fullerenes and their nanocrystal materials.
    Full-text · Article · Oct 2009 · Current Nanoscience
  • [Show abstract] [Hide abstract]
    ABSTRACT: The carbon polyhedrons only composed of pentagons and heptagons (F5F7–Cn) are the analogues of classical fullerenes (F5F6–Cn), but they have been neglected for a long time. Very recently, we have performed a systematical study on classical C60H60 and F5F7–C60H60 without endo C–H bonds and found that the stability of F5F7–C60H60 is comparable to their classical ones. To put further insight into the derivatives of F5F7 polyhedrons, we here performed a systematical density functional theory study on F5F7–C60H60 with 1–10 endo C–H bonds. The calculations demonstrate that some isomers of F5F7–C60H60 are lower in energy than the C60H60 obeying the isolated pentagon rule (IPR) even the parent cages of them are all higher in energy than the IPR one by as much as 350 kcal/mol. Meanwhile, the F5F7–C60H60 with six endo C–H bonds is lower in energy than the IPR C60H60 without endo C–H bond by over 300 kcal/mol. These results demonstrate that F5F7 polyhedrons should not be neglected at all during the search for the favorable derivatives of carbon polyhedrons and that the repulsion between the added atoms plays an important role in determining the stability of the derivatives of carbon polyhedrons.
    No preview · Article · Nov 2012 · Computational and Theoretical Chemistry
Show more