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A calix[3]carbazole-based cavitand was conveniently synthesized. It was found that the cavitand with adjustable conformation could show excellent complexation with fullerenes C60 and C70 in both solution and the solid state. Moreover, the crystal structures of the host–guest complexes show that the cavitand can stack into channel-like architectures, in which fullerenes are orderly arranged inside. [ABSTRACT FROM AUTHOR]

TMB-5 nucleating agent (NA) treated by different solvents were used as the β-NA of iPP. The effects of temperature on the crystalline structure of different iPP/TMB-5, as well as the crystallization and melting behaviors were investigated. It was found that strong polar solvent treated TMB-5 (TMB-5DMSO and TMB-5DMF) could induce more β-crystal at high Tc = 140 °C than the other TMB-5 NAs, while the β-crystal inducing efficiency of untreated TMB-5 (TMB-5UT) and non-polar solvent treated TMB-5 (TMB-5LP) is seriously reduced at high Tc = 140 °C. TMB-5DMSO can induce a high and stable content of β-crystal with Kβ = 83–94% within Tc = 90–140 °C, and TMB-5ODCB can induce a high content of β-crystal with Kβ > 91.3% within Tc = 90–130 °C. TMB-5DMF is the most temperature-sensitive one, but can induce a high fraction of β-crystal with Kβ > 92% both at low Tc = 90 °C and high Tc = 140 °C. High temperature pre-crystallization at Tpc = 150 °C tremendously reduces the β-crystal inducing efficiency of all TMB-5 NAs. TMB-5UT and TMB-5LP exhibit higher nucleating efficiency than TMB-5DMSO, TMB-5DMF and TMB-5ODCB. During the non-isothermal crystallization process, TMB-5UT induced β-crystal possesses higher structural perfection and stability, while TMB-5LP is more likely to induce α-crystal with considerable quantity and stability. The structural perfection and stability of TMB-5 induced β-crystal can be enhanced with appropriate increasing of Tc. [ABSTRACT FROM AUTHOR]

An approach to the highly efficient synthesis of C(sp3)‐bridged [6]cycloparaphenylenes (C[6]CPPs) from fluoren[3]arenes (F[3]As) was developed. Consequently, F[3]As as a new kind of macrocyclic arenes were synthesized. Followed by the demethylation, triflation and intramolecular aryl–aryl coupling reactions, C[6]CPPs were then conveniently obtained. Interestingly, C[6]CPPs could be selectively methylated to produce their fully outer‐methyl‐substituted derivatives. The crystal structures showed the hydroxyl‐substituted F[3]As had bowl‐shaped conformations, and the C[6]CPPs exhibited rigid belt‐shaped structures with deep cavities. Moreover, C[6]CPPs exhibited high HOMO energies and narrow energy gaps. An unclosed belt was further obtained, and it not only showed a similar narrow energy gap to those of the aromatic belts, but also displayed strong fluorescence property, which can play a vital role in the design and synthesis of new aromatic belts. [ABSTRACT FROM AUTHOR]

An approach to the highly efficient synthesis of C(sp3)‐bridged [6]cycloparaphenylenes (C[6]CPPs) from fluoren[3]arenes (F[3]As) was developed. Consequently, F[3]As as a new kind of macrocyclic arenes were synthesized. Followed by the demethylation, triflation and intramolecular aryl–aryl coupling reactions, C[6]CPPs were then conveniently obtained. Interestingly, C[6]CPPs could be selectively methylated to produce their fully outer‐methyl‐substituted derivatives. The crystal structures showed the hydroxyl‐substituted F[3]As had bowl‐shaped conformations, and the C[6]CPPs exhibited rigid belt‐shaped structures with deep cavities. Moreover, C[6]CPPs exhibited high HOMO energies and narrow energy gaps. An unclosed belt was further obtained, and it not only showed a similar narrow energy gap to those of the aromatic belts, but also displayed strong fluorescence property, which can play a vital role in the design and synthesis of new aromatic belts. [ABSTRACT FROM AUTHOR]

Two Schiff-base compounds, 2,6-diacetylpyridine bis(benzoylhydrazone) (abbr. DAPBH) and 2,6-diacetylpyridine bis(benzenesulfonylhydrazide) (abbr. DAPBSH), have been synthesized and characterized. The compound DAPBH reacted with zinc(II) and copper(II) nitrates to give the corresponding complexes 1 and 2 ; the reaction of DAPBSH with zinc(II) acetate and copper(II) nitrate produced complexes 3 and 4 . Single crystal structural analysis revealed that 1 contains novel heptacoordinated zinc(II) species and the copper(II) ion in the crystal structure of 2 shows a rare heptacoordinated pentagonal bipyramidal geometry. Complexes 1 and 3 emit intense luminescence in solution, and a solvent dependent luminescent feature is observed for 1 . In the solid state, complex 3 emits weak luminescence under 365 nm excitation from an ultraviolet lamp. Variable-temperature magnetic susceptibility measurements revealed that there are antiferromagnetic exchange interactions between the neighboring spins in 2 and 4 . [ABSTRACT FROM AUTHOR]

Two rare earth coordination complexes, [Dy(DAPBH)NO 3 (H 2 O) 2 ]⋅(NO 3 ) 2 ( 1 ), La(DAPBH)(NO 3 ) 3 ( 2 ) (where DAPBH = 2, 6-diacetylpyridine benzoyhydrazone), have been synthesized and characterized. Single crystal structural analysis revealed that the Dy 3+ ion is nine-coordinated with three N-atoms and two O-atoms from pentadentate DAPBH ligand, two O-atoms from one nitrate and other two O-atoms from two water molecules, and the coordination sphere features as a capped tetragonal antiprism in 1 , while the La 3+ ion is bound to six O atoms from three nitrate counter ions, three N-atoms and two O-atoms from a pentadentate DAPBH ligand to form a tricapped tetragonal antiprism coordination geometry in 2 . Variable-temperature magnetic susceptibility measurements showed the existence of weak antiferromagnetic interaction in 1 . [ABSTRACT FROM AUTHOR]

The spin Hamiltonian parameters (g factors and zero-field splittings (ZFSs)) and local structures of three Cr(CN) 6 3− centres in NaCl are studied at three temperatures based on the perturbation calculations. The signs and magnitudes of the ZFSs D and E are in accordance with those of average bond length discrepancy Δ R ‾ ( = ( 1 / 6 ) ∑ δ R i , i = 1 – 6 ) and rhombic distortion parameter H ( = - ( Δ φ ‾ ) 1 / 2 ( Δ R ‾ ) 3 / D ) , relevant to average planar bond angle discrepancy Δ φ ‾ ( = ( 1 / 4 ) ∑ δ φ i , i = 1 - 4 ) related to an ideal octahedron. The SHPs exhibit the smallest rhombic (or orthorhombic) distortions and the weakest covalency at 4.2 K, and the largest rhombic distortions and strongest covalency at 77 K with comparable D and E. The magnitude of g-shifts (= g i − g s ) obey the tendency 77 K < 290 K ⩽ 4.2 K, in consistent with that of covalency factor N . The CT contributions to g-shifts are opposite in sign and about 51–63% in magnitude compared with the CF ones. The microscopic mechanisms of the local structures (i.e., the impurity displacements Δ R X and Δ R Y and ligand displacements Δ R P , Δ R P ′ and Δ R P ″) are analyzed for the various centres in view of the electrostatic interactions arising from the cation vacancies. Unlike conventional rhombic centres I and II for all three temperatures, the new orthorhombic centre III occurs only at low temperatures (4.2 K and 77 K) and indeed exhibits new structural properties, especially the largest Δ R ‾ and H as well as D and E. [ABSTRACT FROM AUTHOR]

Abstract: Two luminescent europium complexes, Eu(DAPBH)2(NO3)3·2H2O (1) and Eu(DAPBH)(CH3CH2OH)(SCN)3·H2O (2) (where DAPBH=(1,1′-(pyridine-2,6-diyl)bis(ethan-1-yl-1-ylidene))dibenzohydrazide, have be synthesized and structurally characterized. The Eu3+ ion is 10-coordinated with six N atoms and four O atoms from two pentadentate DAPBH ligands to form a distorted bicapped tetragonal antiprism geometry and the nitrate counter ions are not coordinated to Eu3+ ion in 1, while the 9-coordinate Eu3+ ion is bound to the N atoms of three monodentate thiocyanates (counter ions), three N atoms and two O atoms of a pentadentate DAPBH ligand as well as to the O atom of an ethanol molecule with a distorted monocapped tetragonal antiprism coordination environment in 2. Two complexes exhibit a red luminescence of Eu3+ ion, stemming from the intra-4f transitions, which is contributed to that (1) the coordination sphere of Eu3+ ion completed by pentadentate DAPBH ligands or counter anions effectively protect the excited state of Eu3+ ion from being quenched by water molecules in 1 and 2; (2) there should be a better match between the pentadentate DAPBH ligand triplet excited state and europium 5D0 excited state. [Copyright &y& Elsevier]

• Nine kinds of BaAgAs family topological materials were grown by Flux method. • Energy dispersive X-ray spectroscopy (EDS) spectra to confirm the crystal composition. • X-ray diffraction (XRD) spectra to examine the crystal structure and surface planes. • Quantum Design physical property measurement system (PPMS) was used to study their transport properties. BaAgAs and its family materials MRPn (M = Ca, Sr, Ba, R = Ag, Au, Pn = As, Bi) were theoretically predicted to hold various topological phases. In this paper, the growth method of MRPn family materials was investigated and single crystals were successfully obtained by flux method. The crystal composition was confirmed by the energy dispersive X-ray spectroscopy (EDS). Crystal structure and surface planes were examined by X-ray diffraction (XRD). Temperature-dependent resistivity measurements from 2.5 K to 300 K reveal that all the samples are metallic. [ABSTRACT FROM AUTHOR]

Four Ni(II) reduced Schiff base complexes, {[Ni(L1)(HCOO)(H 2 O)](H 2 O)} ( 1 ), {[Ni(L2)(H 2 O) 3 ](OAc)} ( 2 ), {[Ni(L3)(H 2 O) 3 ](OAc)} ( 3 ) and {[Ni(L4)(HCOO)](H 2 O)} ( 4 ), have been synthesized by the reaction of N-(4-pyridylmethyl)- l -amino acid derivatives and Ni(OAc) 2 ·4H 2 O under hydrothermal conditions. Single-crystal X-ray diffraction analysis reveals all of the four Ni(II) centers in these complexes adopt a six-coordinated octahedral geometry, with complexes 1 – 3 uniformly crystallizing in the monoclinic P 2 1 space group and 4 in the P 2 1 2 1 2 1 space group . A detailed structural study indicates the synergistic effects of the counteranions and steric hindrance of the substituents of the amino ligands lead to the formation of two different dimensionalities of the four compounds, with complexes 1 and 4 featuring 2D layer structures while complexes 2 and 3 exhibiting 1D chain structures. The resulting 3D supramolecular networks are formed by strong hydrogen bonding (O H⋯O and N H⋯O) interactions between the ligands and the guest molecules. The thermal stability, infrared spectra and luminescence properties of these compounds have also been investigated. [ABSTRACT FROM AUTHOR]

Li1.2Ni1/3Co1/3Mn1/3O2 was synthesized as a cathode material for lithium-ion batteries and coated with various amounts of CoAl2O4 (0-5 wt%) at high temperature. The effect of the surface modification on the structure and electrochemical performance of the cathode was evaluated. Microstructural analysis using X-ray diffraction, scanning electron microscopy, and transmission electron microscopy revealed that the CoAl2O4 coating did not affect the crystal structure of the electrode material and that the coating only appeared on the electrode surface. The effect of the CoAl2O4 coating on the electrochemical performance was evaluated by examining charge-discharge cycles, rate performance, and electrochemical impedance. The cathodes coated with CoAl2O4 exhibited improved discharge capacity and cyclic performance compared with those of the uncoated cathode. The electrode coated with 2.5 wt% CoAl2O4 exhibited the highest discharge capacity (202.5 mAhg−1 vs. 185 mAhg−1 for the uncoated material) and highest capacity retention (84.8% for 50 cycles vs. 78.6% for the uncoated material). [ABSTRACT FROM AUTHOR]

Two isomorphous Ln-MOFs, Eu-PTC-DMF and Tb-PTC-DMF, were prepared by solvothermal synthesis method and characterized structurally. Photophysical property measurements reveal that both Ln-MOFs emit characteristic emissions of Ln3+ ions and possess microsecond scale emission lifetime with absolute quantum yields as high as 33.0% and 50.4%, respectively. [Display omitted] Two isomorphous Ln-MOFs with pyridine-2, 4, 6-tricarboxylic acid (H 3 PTC), Eu-PTC-DMF and Tb-PTC-DMF, were prepared by solvothermal synthesis method and characterized by IR spectroscopy, and thermogravimetric analysis, and powder X-ray diffraction techniques. Single-crystal structural analyses indicate that the Ln1 and Ln2 coordination polyhedra are connected by sharing corners of polyhedra to construct 1D chain, which further form a 3D coordination framework through the connection of PTC3- ligands, and the solvent molecules of DMF and H 2 O, as the terminal ligands, are bound to polyhedra of Ln3+ ions. Investigation of the photophysical property at ambient conditions revealed that both Ln-MOFs emit characteristic luminescence of Ln3+ ions. Eu-PTC-DMF and Tb-PTC-DMF possess microsecond scale emission lifetime with absolute quantum yields as high as 33.1% and 50.8%, respectively. [ABSTRACT FROM AUTHOR]

A new salt [H 2 DABCO][Pt(mnt) 2 ] 2 ( 1 ) (mnt 2- =maleonitriledithiolate and H 2 DABCO 2+ is diprotonated 1,4-diazabicyclo[2.2.2]octane) has been synthesized; its crystal structure, magnetic and near-IR absorption properties have been investigated. Two different [Pt(mnt) 2 ] - anions form the strong π-dimers, labeled as Pt(1)-dimer and Pt(2)-dimer, with quite shorter Pt…Pt and S…S distances and molecular plane-to-plane distance (<3.5 Å) within a dimer. The [Pt(mnt) 2 ] 2 2- π-dimers are connected through the cations in the strong H-bond manner to form three-dimensional H-bond supramolecular crystal. The salt shows weak paramagnetism in 1.99–300 K and this is due to the existence of strong antiferromagnetic coupling within a π-dimer. In addition, a small thermal hysteresis loop is observed at ca. 120 K, indicating that a phase transition probably occurs that is further confirmed by variable-temperature IR spectra. Another fascinating functionality of 1 is the intense near-IR absorption in the region of 750–2500 nm, and this near-IR absorption feature makes it to be a promising optical material. [ABSTRACT FROM AUTHOR]

Two Bi-MOFs, [Bi(PDC)(OH)] (Bi-PDC; H 2 PDC ​= ​2,4-pyridine bicarboxylic acid) and [Bi(PTC)(H 2 O) 2 ] (Bi-PTC; H 3 PTC ​= ​2,4,6-pyridine tricarboxylic acid), have been synthesized under almost the same solvothermal condition, respectively. Both Bi-PDC and Bi-PTC were characterized by microanalysis, infrared spectra (IR), thermal gravimetric analyses (TGA), and powder X-ray diffraction (PXRD) techniques. Single-crystal structural analyses indicate that the Bi3+ ions adopt similar coordination sphere of monocapped square antiprism in Bi-PDC and Bi-PTC, while PDC2− and PTC3− ligands display distinct bridging modes through carboxylates and pyridyl groups, leading to Bi-PDC forming three-dimensional (3D) pillared-layer framework and Bi-PTC developing into two-dimensional (2D) layered structure. Two Bi-MOFs emit ligand-centered room temperature phosphorescence due to the heavy atom effect of Bi3+ ion, with lifetime and quantum yield of 0.39 ​ms and 2.49% in Bi-PDC versus 0.57 ​ms and 5.45% in Bi-PTC, and the intense green and orange phosphorescence is visible by naked eyes under ambient condition, and the long-wavelength (orange) phosphorescence Bi-based MOF is seldom reported. Two Bi-MOFs with pyridylmulticarboxylate ligands, Bi-PDC and Bi-PTC, show distinct crystal structures and phosphorescence properties. [Display omitted] • Bi-PDC and Bi-PTC show different crystal packing structures due to distinct bridging modes of ligands. • Bi-PDC and Bi-PTC emit the ligand-centered phosphoresce owing to the heavy atom effect of Bi3+ ion. • Compared with Bi-PDC, the emission peak of Bi-PTC shows significant redshift (83 ​nm). [ABSTRACT FROM AUTHOR]

LaMgNi 3.6 M 0.4 (M = Ni, Co, Mn, Cu, Al) alloys were prepared through induction melting process. The phase compositions and crystal structures were characterised via X-ray diffraction (XRD). The hydrogen storage properties, including activation performance, hydrogen absorption capacity, cycle stability, alloy particle pulverisation and plateau pressure, were systemically investigated. Results show that Ni, Co, Mn and Cu substitution alloys exhibit multiphase structures comprising the main phase LaMgNi 4 and the secondary phase LaNi 5 . However, the secondary phase of the Al substitution alloy changes into LaAlNi 4 . The lattice parameters and cell volumes of the LaMgNi 4 phase follow the order Ni < Co < Al < Cu < Mn. Activation is simplified through partial substitution of Ni with Al, Cu and Co. The hydrogen absorption capacities of all of the alloys are approximately 1.7 wt.% at the first activation process; however, they rapidly decrease with increasing cycle number. In addition, the stabilities of hydriding and dehydriding cycles decrease in the order Al > Co > Ni > Cu > Mn. Hydriding processes result in numerous cracks and amorphisation of the LaMgNi 4 phase in the alloys. The p – c isotherms were determined by a Sieverts-type apparatus. Two plateaus were observed for the Ni, Co and Al substitution alloys, whereas only one plateau was found for Mn and Cu. This result was caused by the amorphisation of the LaMgNi 4 phase during the hydriding cycles. Reversible absorption and desorption of hydrogen are difficult to achieve. Substitutions of Ni with Co, Mn, Cu and Al significantly influence the reduction of hysteresis between hydriding and dehydriding. [ABSTRACT FROM AUTHOR]

Abstract: Electrical interconnects that adopt self-similar, serpentine layouts offer exceptional levels of stretchability in systems that consist of collections of small, non-stretchable active devices in the so-called island–bridge design. This paper develops analytical models of flexibility and elastic stretchability for such structures, and establishes recursive formulae at different orders of self-similarity. The analytic solutions agree well with finite element analysis, with both demonstrating that the elastic stretchability more than doubles when the order of the self-similar structure increases by one. Design optimization yields 90% and 50% elastic stretchability for systems with surface filling ratios of 50% and 70% of active devices, respectively. [Copyright &y& Elsevier]

A series of Zn(II)/Cd(II) coordination polymers based on the chiral ligands of N-(4-pyridylmethyl)- l -Threonine have been synthesized, which can be profoundly regulated by the different positions of carboxylate groups, hydroxyl groups, and pyridyl groups of N-(4-pyridylmethyl)- l -Threonine building blocks and acids auxiliary ligands, as well as metal centers. Their thermal stability and fluorescence properties were also investigated. [Display omitted] Four new coordination polymers based on N-(4-pyridylmethyl)- l -threonine (HL), {[Zn(L)(HCOO)](H 2 O)} n (1), {[Cd(L)(HCOO)](H 2 O)} n (2), {[Zn(L)(H 2 O) 2 ](ClO 4)(H 2 O)} n (3), and {[Cd(L)(H 2 O) 2 ](ClO 4)(H 2 O)} n (4) have been prepared and structurally characterized by X-ray crystallography. Coordination polymers 1 – 4 crystallize in the uniform space group orthorhombic P 2 1 2 1 2 1. Coordination polymers 1 and 2 display two-dimensional lattice frameworks, while 3 and 4 are one-dimensional chain motifs. Interestingly, formate anions can easily coordinate to metal ions in coordination polymers 1 and 2 , while perchlorate anions lead to lower dimension of the coordination assemblies in coordination polymers 3 and 4 with the lattice counter ions. And hydrogen bonding interactions play important roles for the formation and stabilization of these three-dimensional supramolecular networks. Furthermore, the thermal stability, and photoluminescence properties have been investigated. [ABSTRACT FROM AUTHOR]

Abstract: Three new coordination polymers [MnL1(dca)2] n (1) (L1 =1-(2-pyridyl)-4-(2-pyrazinyl)-4-amino-1-methyl-2,3-diaza-1,3-butadiene, dca= ), [CdL2(dca)2] n (2) (L2 =1-(2-pyridyl)- 4-(2-pyrazinyl)-4-amino-2,3-diaza-1,3-butadiene) and [CdL1(dca)2] n (3) have been synthesized, structurally and/or magnetically characterized. In these isostructural compounds, metal ions of octahedral geometry are bridged by double μ1,5-mode dca ions and further interlinked into a 1D ladder-type chain by two single μ1,5-mode dca ions with the Schiff-base ligands acting only as bidentate ligands. Variable temperature magnetic studies have shown that the coupling interaction between Mn(II) centers of the ladder-type Mn-dca chains is weakly antiferromagnetic. [Copyright &y& Elsevier]

Abstract: Three new Mn(II) complexes [Mn(HnicO)2(H2O)2] (1), [Mn2(HnicO)2SO4(H2O)2] n (2), and [NaMn(HnicO)3] n (3) (H2nicO=2-hydroxynicotinic acid) have been synthesized and determined by X-ray diffraction. For complex 1, the mononuclear units with two bidentate HnicO− ions and two water molecules are assembled into a 3D architecture via hydrogen bonding and π–π interactions. For 2, Mn(II) ions are connected by μ 3-HnicO− and bridging ligands, producing a 2D (6,3) coordination network. For 3, binuclear Na(I)–Mn(II) units with three carbonyl oxygen bridges are interlinked by carboxylate groups, resulting in a 3D 6-connected coordination network with distorted α-Po topology. The magnetic properties of 2 are discussed. [Copyright &y& Elsevier]

A simple hydrothermal method was implemented to controllably prepare the mesoporous network "sand rose" NiCoAl hydrotalcite (LDH) on Ni foam (NF). The effect of the Ni/Co/Al molar ratio on crystalline structure, morphology and electrochemical performance was explored systematically, where the LDH 2.0 with a Ni/Co/Al molar ratio of 2.0/1.0/1.0 had the maximum specific capacitance due to the highest crystallinity and uniform configuration with 3D mesoporous network "sand rose" structure. To enhance supercapacitor performance, the LDH 2.0 was covered on the CuCo 2 S 4 nanotube array on NF to assemble CuCo 2 S 4 @LDH electrode material. The as-prepared CuCo 2 S 4 @LDH demonstrated an improved specific capacity with 938 C g−1 (1876 F g−1) at 1.0 A g−1 and super cycling stability (retention of 95.74% after 1000 cycles at 5 A g−1). The enhanced performance was attributed to the unique 3D hierarchically core-shell structure of the CuCo 2 S 4 @LDH and the synergistic effect of the core CuCo 2 S 4 nanotube array on NF and the shell LDH. • The hierarchically core-shell composite of the CuCo 2 S 4 @LDH with 3D mesoporous network structure was designed and prepared. • The crystallinity, morphology and electrochemical performance depend on the Ni/Co/Al molar ratio of the LDH. • The CuCo 2 S 4 @LDH exhibited excellent electrochemical performances and super cycling stability. [ABSTRACT FROM AUTHOR]