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The aggregation behavior of the water-soluble gadofullerene magnetic resonance imaging contrast agent, [Gd(at the rate of)C82O6(OH)16(NHCH2CH2COOH)8].sub. x] is studied in detail by dynamic light scattering, scanning electron microscopy, and atomic force microscopy. It is revealed that this agent aggregation in aqueous solution is pH dependent and at pH 2, it first self-assembles to form a ca. 30 nm small clusters, and then dozens of the small clusters further aggregate to form large grapelike particles.

The synthesis, isolation and spectroscopic characterizations of an endohedral fullerene with four heteroatoms encapsulated (ScYErN at the rate of C80) are described. The findings reveal that the carbon cage of ScYErN at the rate of C80 is assigned as [I.sub.h]-C80 and the four-membered ScYErN cluster is shown to rotate rapidly inside the fullerene cage and six electrons are transferred from the nuclear cluster ScYErN to the fullerene cage.

Research is presented describing the study of isomers to determine Sc atom charge state using both infrared and Raman spectroscopy.

An investigation of the formation mechanism of metallofullerene presented by ab initio calculations with two theoretical models. Both energetic calculations and frequency analyses exclude the 'fullerene-road' mechanism and support the C76 + C6Y growing mechanism, indicating that the involvement of metal atoms would affect the fullerene formation process seriously.

The endohedral fullerene [Sc.sub.3]NC@[C.sub.80]-[I.sub.h] is prepared and analyzed, which has an unprecedented planar quinary cluster in a fullerene cage. The intramolecular dynamics in [Sc.sub.3]NC@[C.sub.80]-[I.sub.h] has enabled the whole molecule to exhibit high polarity and ferroelectricity.

The stable compound [Sc.sub.4][C.sub.2]@[C.sub.80]-[I.sub.h] is produced and characterized as a metal carbide endofullerene by Fourier transform infrared (FTIR) and Raman spectroscopies along with density functional theory (DFT) calculations. DFT calculations have shown that this molecule has a Russian-doll-type structure, [C.sub.2]@[Sc.sub.4]@[C.sub.80].

The synthesis and characterization of two new water-soluble Gd-containing endohedral metallofullerenes is described. The fullerenes could be used as next-generation high-efficiency magnetic resonance imaging contrast agents.

Nanocopper particles can be used as catalysts for the stereospecific polymerization of phenylacetylene (PA) to produce cis-specific and highly crystalline polyphenylacetylene (PPA). Well-aligned PPA nanobelt arrays are obtained via a mild and template-free route and have shown semiconductor features, which can be used in nanodevice applications.

The density functional calculations are used to show that an unprecedented [mu]4-[C2.sup.6-] anion can viably exist as an endohedral [[Sc4C2].sup.6+] cluster in the endofullerene Sc4C2 at the rate of C80. The predicted Sc4C2 at the rate of C80 structure has a stable closed-shell electronic configuration and has a five-membered endohedral cluster.

The synthesis of a stable unconventional unconventional fullerene derivative [C.sub.64][H.sub.4] which was carried out by introducing methane in the fullerene productions with normal Kratschmer-Huffman method is described. Once the four carbon atoms at vertexes of the fused pentagon sites were chemically modified by hydrogen additions, the s[p.sup.2] to s[s.sup.3] hybridization change of the vertex carbon atoms would release remarkably the bond strains, affording the high stability of the [C.sub.64][H.sub.4] structure.

Two-dimensional (2D) assembling behaviors of the endohedral metallofullerene Y(at the rate)C82 on bare, C60-modified and iodine-modified Au(111) surfaces are investigated in 0.1 M HClO4 solution employing electrochemical scanning tunneling microscopy (ECSTM). The improvement of Y(at the rate)C82 dispersion on an iodine-modified gold surface is due to the strong Y(at the rate)C82-substrates interactions and the modified-substrate method provides an effective strategy to disperse endohedral metallofullerenes.

Unconventional fullerenes are those smaller than C60 or those intermediate between C60 and C70, which are not stable in structure as none of the unconventional fullerene isomers satisfying the "isolated- pentagon-rule" (IPR). Below we report the synthesis of a stable unconventional fullerene derivative C64H4 by introducing methane in the fullerene productions with the normal Krätschmer-Huffman method. We also applied various spectroscopic measurements such as mass spectrometry, 13C NMR, IA, UV-vis absorption spectrometry, etc. to characterize the structural and electronic properties of this molecule, revealing an unprecedented fullerene cage with a triplet of directly fused pentagons in the framework of C64H4. Four hydrogen atoms are added to the carbons at vertexes of fused pentagons to allow the bond angles at these sites close to the sp³ tetrahedral angle, which essentially release the sp² bond strains on the abutting-pentagon sites of C64. Ab initio calculations were performed to explore the electronic property and simulate the 13C NMR and lR spectra of this fulleride, which reproduced well the experimental results and confirmed the structural assignment of the C64H4. [ABSTRACT FROM AUTHOR]

The endohedral fullerene Sc3NC@C80-Ih has been synthesized and characterized; it has an unprecedented planar quinary cluster in a fullerene cage. It is also the first chemical compound in which the presence of an unprecedented (NC)3- trianion has been disclosed. The fascinating intramolecular dynamics in Sc3NC@C80-Ih enables the whole molecule to display high polarity and promising ferroelectricity. This finding inspires the possibility that such a planar quinary cluster may be useful in constructing many other endohedral fullerenes. [ABSTRACT FROM AUTHOR]

The article focuses on a study which synthesized, isolated and characterized Sc4C82 through various methods, and demonstrated that the synthesized Sc4C82 is indeed Sc4C2@C80-Ih. The methods used in the study, such as mass spectrometry, are discussed. The study characterized Sc4C2@C80-Ih as a metal carbide endofullerene that featured a Russian-doll-type structure.

The article presents information about catalytic synthesis, structural characterizations and transistor performance of aryl-substituted conjugated polymer polyphenylacetylene (PPA) nanobelts. PPA produced by using the nanocopper particles as catalyst shows single crystalline structure and owns cis-phase conformation. Single PPA nanobelts demonstrate semiconductor features that are stated to demonstrate promising potentials in nanodevice applications.