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All previously reported C 70 isomers have positive curvature and contain 12 pentagons in addition to hexagons. Herein, we report a new C 70 species with two negatively curved heptagon moieties and 14 pentagons. This unconventional heptafullerene[70] containing two symmetric heptagons, referred to as dihept-C 70 , grows in the carbon arc by a theoretically supported pathway in which the carbon cluster of a previously reported C 66 species undergoes successive C 2 insertion via a known heptafullerene[68] intermediate with low energy barriers. As identified by X-ray crystallography, the occurrence of heptagons facilitates a reduction in the angle of the π-orbital axis vector in the fused pentagons to stabilize dihept-C 70 . Chlorination at the intersection of a heptagon and two adjacent pentagons can greatly enlarge the HOMO-LUMO gap, which makes dihept-C 70 Cl 6 isolable by chromatography. The synthesis of dihept-C 70 Cl 6 offers precious clues with respect to the fullerene formation mechanism in the carbon-clustering process., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Despite being widely used as electron acceptor in polymer solar cells, commercially available PC 71 BM (phenyl-C 71 -butyric acid methyl ester) usually has a "random" composition of mixed regioisomers or stereoisomers. Here PC 71 BM has been isolated into three typical isomers, α-, β 1 - and β 2 -PC 71 BM, to establish the isomer-dependent photovoltaic performance on changing the ternary composition of α-, β 1 - and β 2 -PC 71 BM. Mixing the isomers in a ratio of α/β 1 /β 2 =8:1:1 resulted in the best power conversion efficiency (PCE) of 7.67 % for the polymer solar cells with PTB7:PC 71 BM as photoactive layer (PTB7=poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]]). The three typical PC 71 BM isomers, even though sharing similar LUMO energy levels and light absorption, render starkly different photovoltaic performances with average-performing PCE of 1.28-7.44 % due to diverse self-aggregation of individual or mixed PC 71 BM isomers in the otherwise same polymer solar cells., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Previously reported fused-pentagon fullerenes stabilized by exohedral derivatization do not share the same cage with those stabilized by endohedral encapsulation. Herein we report the crystallographic identification of (#4348)C66Cl10, which has the same cage as that of previously reported Sc2@C66. According to the geometrical data of (#4348)C66Cl10, both strain relief (at the fused pentagons) and local aromaticity (on the remaining sp(2)-hybrided carbon framework) contribute to the exohedral stabilization of this long-sought 66 carbon atom cage., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Have a radical ball! Reaction of C(60)Cl(6) with aryl acetylenes through a copper(I)-mediated annulation route to form fullerocyclobutene derivatives is reported. The fullerocyclobutenes are obtained in 36-53% yields and a possible radical mechanism is proposed for this novel reaction., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The hydrofullerene C(50)H(10) is synthesized by low-pressure benzene-oxygen diffusion combustion. The structure of C(50)H(10) is identified through NMR, mass spectrometry, and IR and Raman spectroscopy as a D(5h) symmetric closed-cage molecule with five pairs of fused pentagons stabilized by ten hydrogen atoms. UV/Vis and fluorescence spectrometric analyses disclose its optical properties as comparable with those of its chloride cousin (C(50)Cl(10)). Cyclic and square-wave voltammograms reveal that the first reduction potential of C(50)H(10) is more negative than that of C(50)Cl(10) as well as C(60), with implications for the utilization of C(50)H(10) as a promising electron acceptor for photovoltaic applications., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Porous hollow nanostructures have attracted intensive interest owing to their unique structure and promising applications in various fields. A facile hydrothermal synthesis has been developed to prepare porous hollow nanostructures of silicate materials through a sacrificial-templating process. The key factors, such as the concentration of the free metal cation and the alkalinity of the solution, are discussed. Porous hollow nanostructures of magnesium silicate, nickel silicate, and iron silicate have been successfully prepared by using SiO(2) spheres as the template, as well as a silicon source. Several yolk-shell structures have also been fabricated by a similar process that uses silica-coated composite particles as a template. As-prepared mesoporous magnesium silicate hollow spheres showed an excellent ability to remove Pb(2+) ions in water treatment owing to their large specific surface and unique structures.

Reaction of cupric salts with H(2)Rppz (R = H, Me; H(2)ppz = 3-(2-hydroxyphenyl)pyrazole; H(2)Meppz = 3-(2-hydroxy-5-methylphenyl)pyrazole) in the presence of sodium azide and triethylamine as bases gave two high-nuclearity copper cage compounds [HNEt(3)](2)[Cu(21)(CH(3)CN)(2)(H(2)O)(mu(2)-N(3))(6)(mu(3)-N(3))(2)(ppz)(18)](H(2)O)(3)(EtOH)(2) (1) and [Cu(16)(EtOH)(2)(H(2)O)(2)(Meppz)(16)]9.5 H(2)O (2), respectively. X-ray crystallographic studies revealed that molecular skeletons of 1 and 2 are unique tricorne Cu(21) and saddlelike cyclic Cu(16) aggregates, respectively. The magnetic properties studies showed overall antiferromagnetic interactions in 1 and 2. Quantum Monte Carlo simulations by using a 3-J model for 1 and a 2-J model for 2 were performed, which indicated that the magnetic couplings within the triangular copper units in 1 are ferromagnetic and those between other copper ions are antiferromagnetic, whereas in 2 all magnetic couplings between adjacent copper ions are exclusively antiferromagnetic.