The geometries of pure-carbon fullerenes synthesized thus far follow exclusively the isolated-pentagon rule (IPR), which states that the pentagons in the most stable fullerenes are isolated from each other by hexagons. [1,2] Due to enhanced steric strain (steric effect) and resonance destabilization pertaining to the pentalene-type 8p-electron system (electronic effect), pure-carbon non-IPR fullerenes with abutted pentagons are always unstable and synthetically unattainable.[3] However, it appears that non-IPR fullerenes can be stabilized by either endohedral inclusion of electron-donating metal atoms/clusters [4,5] or exohedral derivatization, [6] as exemplified by such non-IPR fullerene derivatives as the endofullerenes Sc 2 @C 66 , [4b] La 2 @C 72 , [4c] and Sc 3 N@C 68 [5] as well as the exohedral derivative C 50 Cl 10 .[6] On the other hand, many metal-carbide endofullerenes, for example, Sc 2 C 2 @C 84 , [7] Ti 2 C 2 @C 78 , [8] Y 2 C 2 @C 82 , [9] and Sc 3 C 2 @C 80 , [10] have been synthesized and characterized exclusively with IPR-satisfying fullerene cages. Herein we report the isolation and characterization of Sc 2 C 2 @C 68 , which is, to the best of our knowledge, the first metal-carbide endofullerene having a non-IPR cage.

The high-mountain lakes on the Yungui Plateau in China are exposed to high-intensity ultraviolet radiation, and contain low concentrations of chromophoric dissolved organic matter (CDOM). We determined CDOM absorption, fluorescence, composition, and source in 38 lakes on the Yungui Plateau at altitudes of 1516 to 4591 m above sea level. Total nitrogen (TN), total phosphorus (TP), and chlorophyll a (Chl a) concentrations significantly increased with increasing trophic state, and decreased with altitude. The CDOM absorption coefficient a CDOM (280) significantly increased with increasing trophic state, but not with altitude. There were significant and negative correlations between altitude and TN, TP, Chl a concentrations, and a CDOM (280). Parallel factor analysis identified two humic-like and two protein-like fluorescent components. Humic-like component 1 was terrestrially derived and positively correlated to CDOM absorption. Component 2 was similar to a marine humic-like substance originating from biological degradation of phytoplankton. Components 3 and 4 were autochthonous tryptophanlike and tyrosine-like fluorophores. CDOM was, thus, a mixture of material from the catchment and autochthonous material produced by biota in the lake. CDOM fluorescence characteristics of oligotrophic and mesotrophic lakes were dominated by the spectral signatures of protein-like components, but marine and terrestrial humic-like components dominated in eutrophic lakes. The fluorescence indices FI 255 , FI 310 , and FI 370 were useful tools for readily defining and classifying CDOM characteristics in the Yungui Plateau lake waters.

Unconventional fullerenes are those smaller than C(60) or those intermediate between C(60) and C(70), 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 C(64)H(4) by introducing methane in the fullerene productions with the normal Krätschmer-Huffman method. We also applied various spectroscopic measurements such as mass spectrometry, (13)C NMR, IR, 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 C(64)H(4). Four hydrogen atoms are added to the carbons at vertexes of fused pentagons to allow the bond angles at these sites close to the sp(3) tetrahedral angle, which essentially release the sp(2) bond strains on the abutting-pentagon sites of C(64). Ab initio calculations were performed to explore the electronic property and simulate the (13)C NMR and IR spectra of this fulleride, which reproduced well the experimental results and confirmed the structural assignment of the C(64)H(4).

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Two luminescent Zn(II) metal-organic frameworks were prepared from a π-conjugated thiophene-containing carboxylic acid ligand. These two MOFs show strong luminescene and their luminescence could be quenched by a series of nitroaromatic explosives. Importantly, they exhibit very highly sensitive and selective detection of picric acid compared to other nitroaromatic explosives.

Solvothermal synthesis of La(OH)3 sol and microwave radiation drying of La(OH)3 nanorods were employed for the first time to synthesize La2O3 nanorods with diameters around 10 nm and lengths up to 200 nm. The resulting products were characterized with XRD, TEM and HRTEM. Microwave radiation drying was found to be more effective to maintain the morphologies of nanorods than conventional drying.

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