Peng Cheng's scientific contributionswhile working at CUNY Graduate Center (New York City, United States) and other institutions

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Publications citing this author (310)

    • Analogous systems have been prepared with phthalocyanines181182183, tetrathiafulvalene [184,185], vinyl spacers bearing tetrathiafulvalene (TTF) moieties [186,187], along with azides bearing TTF [188], ;7r-extended-TTF units [189,190], and ferrocene [161,185,191192193194. Strapped and parachute-Uke fullerene-porphyrin architectures have been prepared via Bingel reaction with flexible linkers that allow the porphyrin to get very close to the fuUerene195196197198199. Novel CgQ-based [4+2] adducts were recently synthesized through 1,4-dihalide elimination, giving fused TTF-Cgo dyads, Cgo-TTF-Cgo triads200201202203 , and ;r-extened- TTF-Cgo dyads [190], leading to efficient electron and energy transfer through the covalent bonds (Fig. 8).
    [Show abstract] [Hide abstract] ABSTRACT: This chapter reviews the different synthetic methodologies for the covalent functionalization of fullerene along with the most examples in advanced materials-oriented applications. Fullerenes are polyhedral carbon cages in which sp2-carbons are directly bonded to three neighbors in an arrangement of five- and six-membered rings. C60 has been the most extensively studied since its discovery because of its Ih-symmetrical structure, and bulk production. The structure includes two different types of bonds, namely those at the junction of two hexagons, and those at the junction of a pentagon, and a hexagon. The measured bond lengths clearly show that the formal double bonds correspond to the 6-6 junctions, and thus there are no double bonds in the pentagons. The mean diameter of the sphere is ∼7.1 Å. The van der Waals radius of the carbon atoms, the external diameter, is ∼10.4 Å, whereas the inner diameter is ∼3.5 Å. The crystal structure of C60 revealed low-electron delocalization over the spherical surface, and the bond alternation clearly shows a preference for the resonance structure with the 30 double bonds localized at 6-6 junctions. The low delocalization is explained by considering the partial rehybridization of the sp2-C-atoms leading to a higher contribution from the s-orbitals. As a consequence, the double bonds are located exocyclic to the pentagons, providing radialene nature to the five membered rings, and 1,3,5-cyclohexatriene nature to the six-membered rings.
    Chapter · Jun 2006
    • The simplest possible combination of an electron-accepting fullerene is with an electron donor linked by a charge-mediating bridge. As electron donors, a wide range of building blocks—porphyrins3536373839404142434445, phthalocyanines [46,47], amines [48], polycondensed aromatics [49], transition complexes505152, carotenoids [53], ferrocenes [54,55], tetrathiafulvalenes (TTFs) [56], and others [57]—have been employed. Scheme 21-1 summarizes the photophysical processes taking place in a prototype electron donor–acceptor conjugate, that is, ZnP–C 60 (1), and the corresponding energetics in benzonitrile [37].
    [Show abstract] [Hide abstract] ABSTRACT: IntroductionFullerenes in Electron TransferFullerenes in Solar CellsSummaryAcknowledgmentsReferences
    Full-text · Chapter · Sep 2011