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The precise identification of metal–metal bonds is critical to fully understanding the nature of metal–metal bonding but remains a fundamental challenge. Herein, we show the essence of Sc–Sc bonds ...

Monometallic cyanide clusterfullerenes (CYCFs) represent a unique branch of endohedral clusterfullerenes with merely one metal atom encapsulated, offering a model system for elucidating structure-property correlation, while up to now only C82 and C76 cages have been isolated for the pristine CYCFs. C84 is one of the most abundant fullerenes and has 24 isomers obeying the isolated pentagon rule (IPR), among which 14 isomers have been already isolated, whereas the C2v(17)-C84 isomer has lower relative energy than several isolated isomers but never been found for empty and endohedral fullerenes. Herein, four novel C84-based pristine CYCFs with variable encapsulated metals and isomeric cages, including MCN@C2(13)-C84 (M = Y, Dy, Tb) and DyCN@C2v(17)-C84, have been synthesized and isolated, fulfilling the first identification of the missing C2v(17)-C84 isomer, which can be interconverted from the C2(13)-C84 isomer through two steps of Stone-Wales transformation. The molecular structures of these four C84-based CYCFs are determined unambiguously by single-crystal X-ray diffraction. Surprisingly, although the ionic radii of Y3+, Dy3+, and Tb3+ differ slightly by only 0.01 A, such a subtle difference leads to an obvious change in the metal-cage interactions, as inferred from the distance between the metal atom and the nearest hexagon center of the C2(13)-C84 cage. On the other hand, upon altering the isomeric cage from DyCN@C2(13)-C84 to DyCN@C2v(17)-C84, the Dy-cage distance changes as well, indicating the interplay between the encapsulated DyCN cluster and the outer cage. Therefore, we demonstrate that the metal-cage interactions within CYCFs can be steered via both internal and external routes.

Trimetallic carbide clusterfullerenes (TCCFs) encapsulating a quinary M3C2 cluster represent a special family of endohedral fullerenes with an open-shell electronic configuration. Herein, a novel TCCF based on a medium-sized rare earth metal, dysprosium (Dy), is synthesized for the first time. The molecular structure of Dy3C2@Ih(7)-C80 determined by single crystal X-ray diffraction shows that the encapsulated Dy3C2 cluster adopts a bat ray configuration, in which the acetylide unit C2 is elevated above the Dy3 plane by ∼1.66 Å, while Dy–Dy distances are ∼3.4 Å. DFT computational analysis of the electronic structure reveals that the endohedral cluster has an unusual formal charge distribution of (Dy3)8+(C2)2−@C806− and features an unprecedented three-center single-electron Dy–Dy–Dy bond, which has never been reported for lanthanide compounds. Moreover, this electronic structure is different from that of the analogous Sc3C2@Ih(7)-C80 with a (Sc3)9+(C2)3−@C806− charge distribution and no metal–metal bonding., A novel trimetallic carbide clusterfullerene, Dy3C2@Ih(7)-C80, was successfully synthesized and isolated, and the encapsulated Dy3C2 cluster adopts a bat ray configuration featuring an unprecedented three-center single-electron Dy–Dy–Dy bond.

We report a chemical separation method to isolate fullertubes: a new and soluble allotrope of carbon whose structure merges nanotube, graphene, and fullerene subunits. Fullertubes possess single-wa...

All previously reported C70 isomers have positive curvature and contain 12 pentagons in addition to hexagons. Herein, we report a new C70 species with two negatively curved heptagon moieties and 14 pentagons. This unconventional heptafullerene[70] containing two symmetric heptagons, referred to as dihept-C70 , grows in the carbon arc by a theoretically supported pathway in which the carbon cluster of a previously reported C66 species undergoes successive C2 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-C70 . Chlorination at the intersection of a heptagon and two adjacent pentagons can greatly enlarge the HOMO-LUMO gap, which makes dihept-C70 Cl6 isolable by chromatography. The synthesis of dihept-C70 Cl6 offers precious clues with respect to the fullerene formation mechanism in the carbon-clustering process.

It is well-known that the promoter can enhance the selectivity to ethylene oxide (EO) of Ag catalyzed ethylene epoxidation. However, the selectivity enhancement on different crystal planes of Ag catalysts derived from various promoters is still indistinct. In this work, in order to get an atomistic insight into the synergistic effect between crystal planes and promoters on catalytic performance of Ag catalysts, we study ethylene epoxidation on Ag (1 1 1), (1 1 0) and (1 0 0) surfaces with the promoters of Re, Cs and Cu by density functional theory calculations. It is found that selectivity enhancement introduced by the promoters on Ag (1 1 1) surfaces is more obvious compared with that on Ag (1 1 0) and (1 0 0) surfaces. The sequence of EO selectivity on Ag (1 1 0) surfaces is Re

A 2D coordination polymer, {[Zn(btca)(py) 2 ]} n ( 1 ), (H 2 btca = benzotriazole-5-carboxylic acid, py = pyridine), has been prepared with high yield by the hydrothermal reaction of H 2 btca and Zn(NO 3 ) 2 ·6H 2 O in the presence of py, which has been further characterized by kinds of methods combining elemental analysis, thermogravimetric (TG) analysis, infrared (IR) spectrum, powder X-ray diffraction (PXRD), and X-ray single-crystal diffraction. In 1 , each Zn 2+ adopts a five-coordinated pentagonal bipyramid geometry with one O atom from one carboxylate group of btca 2− ligand and four N atoms from two btca 2− ligands and two py molecules. Adjacent Zn 2+ are connected by btca 2− ligands to generate a 2D layer with the ‘ fes ’-type topology, which could further form a 3D supramolecular network through hydrogen bonds interactions. Furthermore, the luminescent results reveal that the detection limit of 1 as a luminescent sensor to probe Cu 2+ and PO 4 3− could reach 3 and 45 ppm, respectively, suggesting that 1 can sensitively and selectively detect Cu 2+ and PO 4 3− in aqueous solution.

Fully phenylated C60Ph6 has never been synthesized in the past two decades largely due to steric effect and poor thermodynamic stability of the initial intermediate towards its isostructural penta-phenyl adduct (C60Ph5X) that has one central site intact. Herein, we report a kinetic management strategy using nitrobenzene that can efficiently alleviate the steric effect in the substitution reaction of C60Cl6 to synthesize C60Ph6. As revealed by X-ray crystallography, the molecule of C60Ph6, in stark contrast to its isostructural C60Ph5Cl with the last chlorine intact, shows a favorable geometrical structure and molecular stacking for electron transport. Furthermore, C60Ph6 shows high LUMO energy of −3.51 eV (0.4 eV higher than that of [6,6]-phenyl-C61-butyric acid methyl ester, PCBM), which is promising high open-circuit voltage for organic solar cells. The merits of both molecular packing and electrochemical property of C60Ph6 lead to high open-circuit voltage of 1.04 V for the OSC device based on poly(3-hexylthiophene) (P3HT). The present C60Ph6 exemplifies a novel class of electronic acceptors with fully aromatized groups on a fullerene cage.

Two-photon (TP) microscopy has advantages for biological imaging in that it allows deeper tissue-penetration and excellent resolution compared with one-photon (OP) microscopy. Herein, two-photon activated nonlinear optical (NLO) materials, a terpyridine derivative ligand with a donor–acceptor (D–A) model and its corresponding four zinc(II) complexes (Z1–Z4), were assembled and fully characterized. Based on their systematic photophysical investigations, it was found that the third-order NLO response in the near-infrared (NIR) region was significantly enhanced for the symmetrical complex Z4 compared with the other asymmetric complexes (Z1–Z3). To further explore its utility in biological systems, Z4 was selected as a two-photon probe for cellular lipid membranes, which was confirmed both by two-photon confocal microscopy and transmission electron microscopy (TEM). Furthermore, it was found that the fluorescence intensity was enhanced for complex Z4 with the addition of bioactive liposomes (1 μg mL−1). Its recognition mechanism was demonstrated by experimental methods, as well as molecular modeling calculations. These findings should open a new pathway for functional metal complexes as lipid membrane targeting probes.

Fused‐pentagons results in an increase of local steric strain according to the isolated pentagon rule (IPR), and for all reported non‐IPR clusterfullerenes multiple (two or three) metals are required to stabilize the strained fused‐pentagons, making it difficult to access the single‐atom properties. Herein, we report the syntheses and isolations of novel non‐IPR mononuclear clusterfullerenes MNC@C76 (M=Tb, Y), in which one pair of strained fused‐pentagon is stabilized by a mononuclear cluster. The molecular structures of MNC@C76 (M=Tb, Y) were determined unambiguously by single‐crystal X‐ray diffraction, featuring a non‐IPR C 2v(19138)‐C76 cage entrapping a nearly linear MNC cluster, which is remarkably different from the triangular MNC cluster within the reported analogous clusterfullerenes based on IPR‐obeying C82 cages. The TbNC@C76 molecule is found to be a field‐induced single‐molecule magnet (SMM).

Buckybowls are fascinating components of supramolecular assemblies owing to their unique bowl-shaped π-surfaces. Herein we present a protocol for the functionalization of a sulfur-doped buckybowl, trithiasumanene, via a brominated intermediate, from which thiolated trithiasumanenes were derived. The curved surface and electron-donating properties of thiolated trithiasumanenes promote their ready assembly with fullerenes to form concave-convex complexes. The supramolecular assembly behavior in solution was investigated by NMR analysis. The structures of supramolecular complexes were unambiguously characterized by crystallography. The crystals of the concave-convex complexes showed high thermal stability and photoconductivity.

The assembly of spherical fullerenes, or buckyballs, into single crystals for crystallographic identification often suffers from disordered arrangement. Here we show a chiral configuration of decapyrrylcorannulene that has a concave ‘palm’ of corannulene and ten flexible electron-rich pyrryl group ‘fingers’ to mimic the smart molecular ‘hands’ for self-adaptably cradling various buckyballs in a (+)hand-ball-hand(−) mode. As exemplified by crystallographic identification of 15 buckyball structures representing pristine, exohedral, endohedral, dimeric and hetero-derivatization, the pyrryl groups twist with varying dihedral angles to adjust the interaction between decapyrrylcorannulene and fullerene. The self-adaptable electron-rich pyrryl groups, susceptible to methylation, are theoretically revealed to contribute more than the bowl-shaped palm of the corannulene in holding buckyball structures. The generality of the present decapyrrylcorannulene host with flexible pyrryl groups facilitates the visualization of numerous unknown/unsolved fullerenes by crystallography and the assembly of the otherwise close-packed spherical fullerenes into two-dimensional layered structures by intercalation., The structures of fullerenes, or buckyballs, are often very difficult to resolve. Here, the authors describe a decapyrrylcorannulene host with ten flexible pyrryl groups that can efficiently co-crystallize with diverse fullerene derivatives in a ‘hand-ball-hand’ fashion, allowing crystallographic identification of commonly known types of fullerenes.

The mechanism that how noncovalent conformation locks (NCLs) to improve the photovoltaic performance of polymer donors was investigated. By developing a model system with three structure-related copolymers W1, W2 and W3, a clear correlation was found between the locking strength in polymer backbone and the photovoltaic performance. W1 with the strongest S⋅⋅⋅O and F⋅⋅⋅H double-side locking gave the highest power conversion efficiency (PCE) of 16.23%, while W2 with a S⋅⋅⋅O single-side locking and W3 with a weakened S⋅⋅⋅O locking caused by Cl–H steric repulsion gave lower PCEs of 11.73% and 0.92%, respectively. With the aid of single crystal X-ray diffraction analysis, density functional theory calculation, grazing-incidence wide-angle X-ray scattering analysis, atomic force microscope study and device characterization, the functions of NCLs in improving the planarity, packing, crystallinity and hole mobility of polymers, as well as the morphology of blend films, were illuminated in detail.

Bingel-Hirsch reactions of trimetallic nitride clusterfullerenes (NCFs) generally yield methanofullerene (cyclopropane) adducts instead of singly bonded derivatives, which have been reported for monometallofullerenes. Herein, we report the synthesis and characterization of the Bingel-Hirsch derivative of a mixed metal nitride clusterfullerene (MMNCF) TiY2 N@Ih -C80 . Surprisingly, in contrast to the reported Bingel-Hirsch cyclopropane adducts of the analogous NCF Y3 N@Ih -C80 , the Bingel-Hirsch derivative of TiY2 N@Ih -C80 is the first singly bonded monoadduct (labeled as TiY2 N@C80 -Mono) to be reported, which was determined unambiguously by single-crystal X-ray crystallography. Besides, the reactivity of TiY2 N@Ih -C80 was found to be significantly improved relative to that of Y3 N@Ih -C80 . Upon substituting one endohedral yttrium (Y) atom of Y3 N@Ih -C80 with titanium (Ti), the Bingel-Hirsch derivative changes from the cyclopropane to the singly bonded monoadduct, revealing that not only the reactivity but also the addition pattern of NCFs can be manipulated simultaneously through one endohedral metal atom substitution.

So far the entrapped metals for the isolated endohedral metallofullerenes (EMFs) are primarily limited to rare earth metals, whereas except group-IVB metals, whether it is possible to entrap other d-block transition metals remains unclear. Herein we report the successful entrapment of the group-VB transition metal vanadium(V) into fullerene cage, affording the heretofore unknown V-containing EMFs. Two novel V-containing EMFs--V(x)Sc(3-x)N@C80 (x = 1, 2)--were isolated, and their molecular structures were unambiguously determined by X-ray crystallography to be I(h)(7)-C80 cage entrapping the planar VSc2N/V2ScN clusters. V(x)Sc(3-x)N@I(h)(7)-C80 (x = 1, 2) were further characterized by UV-vis-NIR and ESR spectroscopies and electrochemistry, revealing that the electronic and magnetic properties of V(x)Sc(3-x)N@I(h)(7)-C80 (x = 1, 2) are tunable upon varying the number of entrapped V atoms (i.e., x value). The molecular structures and electronic properties of V(x)Sc(3-x)N@I(h)(7)-C80 (x = 1, 2) were further compared with those of the reported analogous EMFs based on lanthanide metals and the adjacent group-IVB transition metal Ti, revealing the peculiarity of the group-VB transition metal V-based EMFs.

A heteronuclear metal organic framework containing erbium(III) and cobalt(II) ion based on a rigid ligand of substituted imidazoledicarboxylic acid has been synthesized and characterized by single-crystal X-ray diffraction analysis (CIF file CCDC no. 1019455). It’s formula is [Er2Co2(μ3-HMimda)2(μ3-Mimda)2 · 4H2O] n · 2nH2O, (H3Mimda = 1-H-2-methyl-4,5-imidazole-dicarboxylic acid). The complex crystallizes in the monoclinic system. It possesses an extended grid-like porous structure constructed from corrugated shaped 2D layer. Direct current magnetic susceptibility measurements for indicated the depopulation of the Stark components at low temperature and possible very weak antiferromagnetic interactions within heteronuclear MOF.

The reactions of methyl-4-(pyrimidin-2-ylcarbamoyl)benzoate ( L ) with Co(II), Ni(II), Cu(II) and Cu(I) metal salts afforded [Co( L ) 2 (CH 3 OH) 2 ](ClO 4 ) 2 ( 1 ), [Co( L ) 2 (CH 3 OH) 2 ](BF 4 ) 2 ( 2 ), [Ni( L ) 2 (CH 3 OH) 2 ](BF 4 ) 2 ( 3 ), [Cu( L ) 2 (ClO 4 ) 2 ]·2CH 3 OH ( 4 ), [Cu( L ) 2 (BF 4 ) 2 ]·2CH 3 OH ( 5 ), [Cu( L ) 2 Br 2 ]·CH 3 OH ( 6 ), [Cu 2 ( L )Cl 4 ·CH 3 CN] ∞ ( 7 ), [Cu 3.5 ( L )Br 4 ·0.5C 2 H 5 OC 2 H 5 ] ∞ ( 8 ) and [Cu 2 ( L )I 2 ] ∞ ( 9 ), which have been structurally characterized by X-ray crystallography. Four types of ligand conformation-coordination mode, cis -bidentate, cis -tridentate, trans -bidentate and trans -tridentate, are observed for the L ligand in these complexes, resulting in mononuclear structures for 1 – 6 , layer structures for 7 and 8 and a chain structure for 9 . C–H⋯π and π⋯π interactions and various hydrogen bonds are found in these complexes that extend the dimensionalities of the structures, and the structural types of the copper halide aggregates in 7 – 9 are unique.

Four fullerene derivatives, benzocyclopentane-C 60 mono-adduct (BPCMA) and its bis-adduct (BPCBA), acenaphthene-C 60 mono-adduct (ACMA) and its bis-adduct (ACBA), were synthesized by cyclopropanation reaction. Geometrical structures and molecular packing of the mono-adduct compounds (BPCMA and ACMA) were identified by X-ray crystallography. As measured by cyclic voltammetry, LUMO energy levels of BPCBA and ACBA are about 0.08 and 0.09 eV higher than their corresponding mono-adducts. Even though the power conversion efficiency remains to be improved, the polymer solar cells (PSCs) incorporating P3HT as donor and BPCBA (or ACBA) as acceptor exhibit open-circuit voltage ( V oc ) of 0.67 V (or 0.68 V), which is about 0.22 V (or 0.23 V) higher than the PSCs with the mono-adduct BPCMA (or ACMA) as electron acceptor. In addition, the short-circuit current density ( J sc ) of the PSCs involving bis-adducts (BPCBA and ACBA) are obviously higher than those based on BPCMA and ACMA. The photovoltaic difference between mono- and bis-adducts can be rationalized by their different behaviors in LUMO energy and molecular packing.

Using Ca(NO3)2·4H2O, (NH4)2HPO4 and ammonia water as the starting raw materials and L-DOAP as template, hydroxyapatite (HAP) crystals were successfully prepared at 180 °C by changing the hydrothermal time. The HAP crystals were characterized by X-ray diffractometry (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (FESEM). The XRD patterns indicate that increasing hydrothermal time is helpful to improve the purity of the product and enhance crystallinity of HAP crystal. The FTIR analysis shows that the carbonate ions enter into the HAP crystal lattice and the final products are carbonate-containing hydroxyapatite. The FESEM images illustrate that HAP crystal morphology changed to flower-like hierarchical structures and grass blanket-like hierarchical structures when increasing the hydrothermal time to 1 h and 24 h. Therefore, hydrothermal time has a great influence on the morphology of HAP and the possible formation mechanism of HAP samples has been discussed.

By using isomeric N,N′-di(2-pyridyl)adipoamide (L1), N,N′-di(3-pyridyl)adipoamide (L2) and N,N′-di(4-pyridyl)adipoamide (L3) and isomeric 1,2-benzenedicarboxylic acid (1,2-H2BDC), 1,3-benzenedicarboxylic acid (1,3-H2BDC) and 1,4-benzenedicarboxylic acid (1,4-H2BDC), eight Zn(II) and Cd(II) coordination polymers [Zn(1,2-BDC)(L2)]∞, 1; [Zn2(1,3-BDC)2(L2)(H2O)2]∞, 2; [Zn2(1,4-BDC)2(L1)(H2O)2]∞, 3; {[Zn2(1,2-BDC)2(L3)(H2O)2]·2H2O}∞, 4; {[Cd(1,2-BDC)(L2)(H2O)]·H2O}∞, 5; [Cd2(1,3-BDC)2(L2)(H2O)4]∞, 6; {[Cd2(1,4-BDC)2(L2)2]·(H2O)3}∞, 7; [Cd2(1,4-BDC)2(L1)(H2O)2]∞, 8, have been synthesized under hydrothermal conditions. Complexes 1, 4, and 5 form 1D double-looped chain, 1D chain with loops and 2D layer with loops, respectively, and complex 6 exhibits a 1D ladder chain. Complex 2 shows rare 3-fold interpenetrated hcb layers, in which each layer interdigitates with other four parallel layers by directing the 1,3-BDC ligands into the windows of the adjacent nets, whereas complexes 3 and 8 forms planar and undulated ...

The genome of the Synechococcus elongatus strain PCC 7942 encodes a putative sugar kinase (SePSK), which shares 44.9% sequence identity with the xylulose kinase-1 (AtXK-1) from Arabidopsis thaliana. Sequence alignment suggests that both kinases belong to the ribulokinase-like carbohydrate kinases, a sub-family of FGGY family carbohydrate kinases. However, their exact physiological function and real substrates remain unknown. Here we solved the structures of SePSK and AtXK-1 in both their apo forms and in complex with nucleotide substrates. The two kinases exhibit nearly identical overall architecture, with both kinases possessing ATP hydrolysis activity in the absence of substrates. In addition, our enzymatic assays suggested that SePSK has the capability to phosphorylate D-ribulose. In order to understand the catalytic mechanism of SePSK, we solved the structure of SePSK in complex with D-ribulose and found two potential substrate binding pockets in SePSK. Using mutation and activity analysis, we further verified the key residues important for its catalytic activity. Moreover, our structural comparison with other family members suggests that there are major conformational changes in SePSK upon substrate binding, facilitating the catalytic process. Together, these results provide important information for a more detailed understanding of the cofactor and substrate binding mode as well as the catalytic mechanism of SePSK, and possible similarities with its plant homologue AtXK-1.

The triple sequentially fused pentagons (TSFP) motif is one of the basic subunits that could be used for constructing fullerenes, but it violates the isolated pentagon rule (IPR) and has not been found in carbon cages to date. The properties of TSFP-incorporating fullerenes are thus poorly explored both theoretically and experimentally. Reported herein are four chlorinated derivatives of three different fullerene cages, all with the TSFP motif. X-ray crystallographic analyses indicate that the molecular strain inherent to the pentagon adjacency of a TSFP is significantly relieved upon exohedral chlorination, leaving one of the four pentagon fusion sites unsaturated and rendering the present derivatives chiral. This unique reactivity, in stark contrast to that of previously reported non-IPR fullerenes containing double fused pentagons or triple directly fused pentagons, can be rationalized by density functional theory calculations, and are expected to stimulate further studies of these new members of the fullerene family, both theoretically and experimentally.

Pure non-IPR (isolated-pentagon-rule) C 60 isomer has rarely been investigated experimentally. The recently reported availability of #1809 C 60 Cl 8 opens an avenue for experimental investigation of #1809 C 60 , a C 2v -symmetric C 60 isomer having two pairs of fused pentagons. Herein, the experiments on #1809 C 60 were performed on the basis of thermal dechlorination of #1809 C 60 Cl 8 in the solid state and gas phase. #1812 C 60 Cl 6 was employed for comparative study. As determined by Raman and other methods, #1809 C 60 from thermal decomposition of #1809 C 60 Cl 8 crystals readily coalesces to form carbon solid with a collapsed crystal lattice. In contrast, dechlorination via thermal spray of #1809 C 60 Cl 8 in the gas phase is feasible for investigation of monodispersed all-carbon C 60 isomer, because the existence of #1809 C 60 in the gas phase has been confirmed by experimental evidence from mass spectrometry and high-performance-liquid-chromatography.

1,6-Bis(4-methoxyphenylsulfanyl) perchlorofluoranthene, a molecule with a dramatic orientation effect due to intramolecular aromatic π–π interactions (APPI), was synthesized and characterized using X-ray diffraction, DFT calculations, UV–vis absorption spectra, and excitation spectra. The crystals are monoclinic, space group P2(1)/ n with a = 7.9707(10), b = 18.349(2), c = 20.649(3) A, β = 95.259(3)°, V = 3007.3(7) A 3 and Z = 4. The flexibility of the five-membered ring in the molecule was shown to facilitate the intramolecular APPI formation.

The long-sought small-bandgap endohedral fullerene Sc3N@C82 with low kinetic stability has been successfully synthesized and isolated for the first time, for which the molecular structure has been unambiguously determined as Sc3N@C82-C2v(39718) by single crystal X-ray diffraction. The C82-C2v(39718) (or labeled as C82-C2v(9) according to the conventional numbering of the isolated pentagon rule (IPR) isomers based on the Fowler-Monolopoulos spiral algorithm) isomeric cage of Sc3N@C82 agrees well with its most stable isomer previously predicted by DFT computations and is dramatically different to those of the reported counterparts M3N@C82-Cs(39663) (M = Gd, Y) based on a non-IPR C82 isomer, revealing the strong dependence of the cage isomeric structure on the size of the encaged metal for C82-based metal nitride clusterfullerenes (NCFs).

Crystal structure analysis shows that the p-tert-butylcalix[8]arene host and its four pyridine guests sit around an inversion center in the P21/c crystal lattice. The monoclinic cell parameters and its volume are: a = 19.617(4), b = 9.912(2), c = 25.178(5) Β, β = 101.03(3)°, V =4805.27(17) Β3. For Z = 2 and Mw = 1614.18, the calculated density Dcalc = 1.116 g/cm3. A host calixarene molecule includes four pyridine guests in two different ways: by hydrogen bonding and by possible C–H· π interaction between the molecules. The hydrogen bonding drives the host macrocycle into a chair-like conformation.

The title compound, [CuI(C(11)H(10)N(2)S(2))](n), is built around centrosymmetric dinuclear Cu(2)I(2) cores, each of which is linked to four neighboring Cu(2)I(2) units via flexible dithioether ligands, viz. 4,4'-(methylenedithio)dipyridine, to form a two-dimensional grid containing rhombus-shaped cavities with diagonal distances of ca 15 and 22 A. Two of these networks interpenetrate in a woven fashion, and the resulting structure does not possess any open channels or cavities. Each Cu atom is in a distorted tetrahedral coordination environment.

Boron is the fifth element and next to carbon in the periodic table of the elements, but boron has been researched less than its neighbor carbon. Borax sourced from a natural boronrich mine in Yamdrok Lake, Tibet, China, has been used as a fusion agent to make glass from ancient times. Elemental boron, however, was elusive until 1808 when it was prepared from electrolysis of melted boron trioxide or by reducing boric acid with potassium. Structures of elemental boron include an icosahedral (Ih) B12 motif connected in an ordered manner, as exemplified by α-rhombohedral boron (Fig. 1a). The dangling bonds in each Ih-B12 unit can be saturated by hydrogen to produce borane species. In stark contrast to the ubiquitous Ih-B12 unit in elemental boron allotropes and boranes, a different B12 all-boron clusterwith aC3v-symmetric planar structure that resembles a solid disk with three boron atoms in the center surrounded by a peripheral ring of boron atoms has also been observed (Fig. 1b) [1]. With six delocalized π electrons that exhibit ‘disk delocalization’, the planar B12 cluster is analogous to benzene with its wellknown cyclic delocalization. Bn clusters adopt 2D planar or quasi-planar structures even up to n = 36 [2]. Because of their diverse set of structural and bonding characteristics, scientists believe that boron and carbon form a set of complementary chemical systems and have long been fascinated with whether or not structures such as cage-like all-boron clusters are as prevalent as all-carbon fullerenes. A series of all-boron cage configurations stabilized by three-center Figure 1. The structures of all-boron clusters (B12 and B40). (a) Icosahedral B12 motifs bound by threecenter two-electronσ bonds (indicated by dashed lines) to form a B12 layer inα-rhombohedral boron; (b) Top and side views of a C3v-symmetric B12 cluster; (c) Top and side views of Cs-symmetric B40 with two adjacent hexagonal holes; (d) Top and side views of a neutral B40 cluster with two hexagonal and four heptagonal holes. This figure was redrawn according to the coordinates of a B40 cluster provided in the supplementary information of [5].

A "basophilic method" for phenolic hydroxyl bridged lanthanide coordination polymers (CPs) was developed. With this method, eleven CPs with the general formula of [Ln(HL1)L1·H(2)O](n) (Ln = Tb (1), Nd (2), Eu (3), Gd (4), La (5), Er (6), Y (7), H(2)L1 = 4-methyl salicylic acid) and [Ln(HL2)L2·2MeOH](n) (Ln = Eu (8), Tb (9), Gd (10), La (11), H(2)L2 = 3-hydroxy-2-naphthoic acid) were synthesized based on two ligands, and five of them (1-4 and 8) were characterised by X-ray single crystal diffraction. The powder X-ray diffraction patterns (PXRD) of complexes showed that 1-7 are isostructural, 8-11 are isostructural. Furthermore, 1 was characterised by Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), differential thermal analysis (DTA), elemental analysis (EA), one and two photon luminescence were investigated in detail.

UV spectra of 16 p-Y-substituted phenylacetylenes (I-Ys), nine p-Y-substituted acetophenones (2-Ys) and six p-Y-substituted-p′-methylsulphonylstilbenes (3-Ys) were measured and correlated against spin-delocalization substitutent constants (σ.) with confidence levels above 99·9%. UV spectra of five ethyl 3-hydroxy-3-(p-Y-substituted-phenyl)-propanates (4-Ys) and five 1-(p-Y-substituted-phenyl)-3-butyn-1-ols (5-Ys) were also measured. Correlation analysis results are discussed. Some literature UV data were also successfully correlated by the dual-parameter equation.

National Basic Research 973 Program of China [2011CB935901]; National Nature Science Foundation of China [21031004, 21021061]; NFFTBS [J1030415]

A long-sought empty non-IPR fullerene, (#11188)C72, which is more stable than the sole IPR isomer in the fullerene[72] family, has been retrieved and crystallographically characterized as (#11188)C72Cl4. Mass spectrometric data support the facile dechlorination of (#11188)C72Cl4 and, in turn, the possible stability of pristine (#11188)C72.

In the title compound, C15H8O, the asymmetric unit contains four independent molecules and crystallizes with aromatic π–π stacking interactions[centroid–centroid distances = 3.5326 (18) Å].

In the molecule of the title compound, C14H8Cl2N4S, all the ring atoms in the pyrazolopyrimidine system are almost coplanar, the largest deviation from the mean plane being 0.027 (2) Å for a C atom. The conformation of the methylsulfanyl group is antiperiplanar, with a torsion angle of −176.7 (2)°. A weak intermolecular C—H...N hydrogen bond and a Cl...N halogen bond [Cl...N = 3.196 (5) Å] with a nearly linear N...Cl—C angle [174.2 (1)°] link the molecules into a two-dimensional assembly. Face-to-face π–π stacking, with a centroid–centroid separation of 3.557 (2) Å and an angle of 7.1 (1)° between the two planes, completes the intermolecular interactions in the solid state.

The title complex, [Cu4I4(C21H15N3)2], lies on an inversion centre located at the centroid of a four-membered ring formed by one of the crystallographically independent CuI ions and a triply bridging iodide ligand. The 2,2′:6′,2′′-terpyridine (phterpy) ligand chelates each of the independent CuI centres in a bidentate fashion, with the N atom of the central pyridyl ring bridging the two CuI centres and those of the outer pyridyl rings binding the two independent CuI ions individually to form a dinuclear system. These are further linked by triply-bridging I− anions to form the centrosymmetric tetranuclear units. One independent Cu atom binds to each of the inversion-related I− anions while the other coordinates to one bridging and one terminal monodentate iodide ligand. The outer pyridyl rings are twisted relative to the central pyridyl ring of the phterpy ligand with dihedral angles of 18.7 (1) and 35.6 (1)°, respectively.

The title compound, C30H25Cl2NO3, was prepared by the reaction of 3-oxo-N,3-diphenylpropanethioamide, 2,5-dichlorobenzaldehyde and 5,5-dimethyl-1,3-cyclohexanedione (1:1:1) in ethanol. The cyclohexene ring adopts a half-chair conformation. The crystal structure exhibits intramolecular N—H...O and C—H...O, and intermolecular C—H...O interactions.

The title complex, [Cu(4)I(4)(C(21)H(15)N(3))(2)], lies on an inversion centre located at the centroid of a four-membered ring formed by one of the crystallographically independent Cu(I) ions and a triply bridging iodide ligand. The 2,2':6',2''-terpyridine (phterpy) ligand chelates each of the independent Cu(I) centres in a bidentate fashion, with the N atom of the central pyridyl ring bridging the two Cu(I) centres and those of the outer pyridyl rings binding the two independent Cu(I) ions individually to form a dinuclear system. These are further linked by triply-bridging I(-) anions to form the centrosymmetric tetra-nuclear units. One independent Cu atom binds to each of the inversion-related I(-) anions while the other coordinates to one bridging and one terminal monodentate iodide ligand. The outer pyridyl rings are twisted relative to the central pyridyl ring of the phterpy ligand with dihedral angles of 18.7 (1) and 35.6 (1)°, respectively.

A smaller fullerene C56 (#913) is stabilized, isolated, and crystallographically characterized as C56Cl10. The geometric parameters of C56Cl10 imply the otherwise unstable cage of C56 can be stabilized by chlorination through releasing its surface strains and maintaining fragmental aromaticity. An unexpected C Cl...ClC short contact, as well as the linear alignment with pearl-necklace-shaped, is revealed in C56Cl10 crystal.

Reactions of the flexible N,N′-di(3-pyridyl)dodecanediamide (L) with Zn(II) and Cd(II) metal salts in the presence of different polycarboxylic acids under hydrothermal conditions afforded five new coordination polymers, [Zn(2,4-PDC)(L)(H2O)]∞ (2,4-H2PDC = 2,4-pyridinedicarboxylic acid), 1, {[Zn(1,3,5-HBTC)(L)]·2H2O}∞ (1,3,5-H3BTC = 1,3,5-benzenetricarboxylic acid), 2, {[Zn(3,4-PDC)(L)]·0.5L}∞ (3,4-H2PDC = 3,4-pyridinedicarboxylic acid), 3, {[Cd(1,2-BDC)(L)(H2O)]·0.5L}∞ (1,2-H2BDC = 1,2-benzenedicarboxylic acid), 4, and {[Cd(1,3,5-HBTC)(L)1.5]·2H2O}∞, 5, which have been structurally characterized by X-ray crystallography. Complexes 1 and 2 manifest quintuple and double helices formed by zinc ions and L ligands, which are supported by 2,4-PDC2− and 1,3,5-HBTC2− anions, respectively, to construct the rare single-walled metal–organic nanotubes. Complex 3 shows 1D fish-bone chains and complexes 4 and 5 display 2D pleated grids with helical and looped carboxylate chains, respectively, supported by the L ligands. Complexes 1–3 represent a unique example of the polycarboxylate ligands showing a significant effect on folding and unfolding of the Zn(II) helical coordination polymers, and they are also important in determining the number of helices. The L ligands in 1, 2 and 4 adopt a bidentate bonding mode, and a unique monodentate bonding mode for the dipyridyl amide ligand is found in 3 and 5, resulting in various types of ligand conformations.

Eight new Zn(II) and Cd(II) coordination networks containing N,N′-di(3-pyridyl)adipoamide (L) and polycarboxylate ligands, {[Zn2(2,5-PDC)2(L)(H2O)2]·2H2O}∞ (H2PDC = 2,5-pyridinedicarboxylic acid), 1, [Zn2(2,6-PDC)2(L)]∞, 2, {[Zn2(3,4-PDC)2(L)(H2O)6]·4H2O}∞, 3, {[Cd(2,6-PDC)(L)(H2O)]·4H2O}∞, 4, [Zn(1,3,5-HBTC)()]∞ (H3BTC = benzenetricarboxylic acid), 5, {[Cd(1,2,3-HBTC)(L)(H2O)]·H2O}∞, 6, {[Cd2(1,3,5-HBTC)2(L)(H2O)2]·2H2O}∞, 7, and {[Zn3(1,2,4-BTC)2(L)(H2O)4]·4H2O}∞, 8, have been synthesized by hydrothermal reactions and characterized by single crystal X-ray crystallography. Structural analysis reveals that 1 and 2 form pleated hcb layers with 1D helical chains, in which the layers of 1 interdigitate with each other and those of 2 are linked by the π–π stacking interactions. Complexes 3 and 4 exhibit 1D ladders with single and double rungs, respectively, whereas 5 shows a 2D pleated net with the sql topology, 6 displays a 3D dia coordination network and 7 forms a 2D structure with the (63)(66)-3,4L88 topology. The BTC3− ligands in 8 adopt the μ4-bonding modes, resulting in a 3D coordination network with the rare (65·8)-hxg-d-4-P2/c topology. The various bonding modes, the ligand-isomerism of the polycarboxylate ligands and the identity of the metal center play important roles in determining the structural diversity. Their thermal and luminescent properties are also discussed.

All C70 isomers other than the well-known D5h-symmetric C70 (#8149) are highly elusive due to their defiance of the isolated pentagon rule (IPR), and, in turn, have long been underrated for years. Here we show a non-IPR hollow C70 (#8064) with C2-symmetry stabilized by exohedral chlorination as #8064C70Cl10. Its connectivity with two pairs of fused pentagons was determined unambiguously by single crystal X-ray diffraction analysis. Based on the geometric criterion in terms of the pyramidalization angle as well as theoretical computations on the Kekule structure and the negative nucleus independent chemical shift, the exohedral stabilization of the labile #8064C70 is rationalized by releasing the local strain relevant to the fused pentagons and achieving the aromaticity of the remaining sp2-hybridized carbon framework in the exohedral derivative of #8064C70. This new entrant in the C70 family, in addition to two previously reported non-IPR isomers (by Yang, Dunsch et al. for Sc3N@#7854C70 and by Echegoyen et al. for Sc2S@#7892C70), provides valuable opportunities for experimental and theoretical research involving non-IPR isomers of C70 beyond the common D5h-C70.

The title compound, C18Cl12O2, was synthesized by a solvothermal reaction between sodium and carbon tetrachloride; the oxygen may come from air. The mol­ecule has crystallographic C2 symmetry and contains a four-membered ring, two five-membered rings and two six-membered rings. The five-membered rings are attached to opposite sides of the cyclo­butane group and the six-membered rings are fused to the five-membered rings. In the solid state, the mol­ecule adopts a boat form.

Reactions of silver(I) salts with the isomeric pyridyl amide ligands methyl-4-(pyridin-2-ylcarbamoyl)benzoate (L1), methyl-4-(pyridin-3-ylcarbamoyl)benzoate (L2) and methyl-4-(pyridin-4-ylcarbamoyl)benzoate (L3) and the pyrimidyl amide ligand methyl-4-(pyrimidin-2-ylcarbamoyl)benzoate (L4) afforded the complexes Ag4(L1)4(NO3)4, 1, [Ag(L2)2][Ag(NO3)2], 2, [Ag(L2)2](ClO4), 3, [Ag(L2)2](ClO4)·2CH3CN, 4, [Ag(L3)2](NO3), 5, [Ag(L3)2](ClO4)·CH3CN, 6, and [Ag(L4)2](X) (X = ClO4−, 7; BF4−, 8; PF6−, 9), which were structurally characterized by X-ray crystallography. The L1–L3 ligands in 1–6 adopt monodentate bonding modes, which coordinate to the metal centers through the pyridyl nitrogen atoms, whereas the L4 ligands of 7–9 adopt a bidentate mode, featuring chelation through one pyrimidyl nitrogen atom and the amide oxygen atom. All nine complexes adopt discrete structures with 1 being tetranuclear and 2–9 being mononuclear. Moreover, Ag⋯Ag short contacts, π⋯π stacking interactions and/or Ag⋯O interactions are found in these complexes which extend the dimensionalities of the structures. The changes of the donor atom positions and counteranions significantly affect the supramolecular structures of these complexes and the L1–L4 ligands are sufficiently flexible to adopt the cis and/or trans conformations.

The title compound, C13H9BrO, has been synthesized by the intramolecular Friedel–Crafts reaction of 1-(1-bromo-4-naphthyl)-3-chloropropan-1-one. There are two approximately planar [maximum deviations of 0.8 (2) and 0.4 (2) Å in the two molecules] molecules in the asymmetric unit. The dihedral angle between their mean planes is 19.72 (8)°. Weak intermolecular C—H...O hydrogen bonding is present in the crystal structure.

The molecule of the title compound, C17H10O, is nearly planar, the largest deviation from the mean plane being 0.06 Å. The crystal structure is governed by π–π interactions, with centroid–centroid distances ranging from .559 to 3.730 Å.

Each of the six Br atoms in the title compound, C15H12Br6, connects to an α-C atom; a pair of adjacent Br atoms connecting to the same five-membered ring extends to one side of the mol­ecular framework and the other two pairs to the other side. The β-C atoms extend in the opposite direction with respect to the pairs of Br atoms.