[Al4(OH)2(OCH3)4(H2N‐bdc)3]⋅x H2O: A 12‐Connected Porous Metal–Organic Framework with an Unprecedented Aluminum‐Containing Brick

Al together now! A new stable aluminum aminoterephthalate system contains octameric building blocks that are connected by organic linkers to form a 12‐connected net (see picture). The structure adopts a cubic centered packing motive in which octameric units replace individual atoms, thus forming distorted octahedral (red sphere) and tetrahedral cages (green spheres) with effective accessible diameters of 1 and 0.45 nm, respectively.

     

A High‐Temperature Order–Disorder Phase Transition Coupled With Conformational Change in the Hybrid Material [C6H13NH]2⋅ZnBr4

A new high‐temperature, hybrid, phase‐transition material, 1‐methylpiperidinium tetrabromozincate ( 1 ), that shows a reversible transition at 345 K was synthesized. Differential scanning calorimetry and specific heat capacity measurements confirmed this reversible transformation with a large heat hysteresis of 25 K, which describes a typical first‐order phase transition in 1 . The dielectric constant exhibited a steplike anomaly and showed high and low dielectric states in the high‐ and room‐temperature phases, respectively, and therefore, this hybrid might be considered as a potential switchable dielectric material. The variable‐temperature powder X‐ray diffraction patterns displayed remarkable shifts between the experimental patterns at the two different phases. Single‐crystal X‐ray diffraction analyses at various temperatures revealed that the origin of this transformation could be attributed to disordering of the bromine atoms in the anion and the nitrogen atom of the cation. The cation also assumed a conformational change, which was likely induced by the disordered nitrogen atom. The conformational onset of the transformation of the cation from a planar conformer into a relaxed chair also occurred upon decreasing the temperature below transition point; thus, the combined order–disorder and conformational change induced the structural transformation and the change in symmetry.     

New 3 D Tubular Porous Structure of an Organic–Zincophosphite Framework with Interesting Gas Adsorption and Luminescence Properties

A new 3D tubular zinc phosphite, Zn₂(C₂₂H₂₂N₈)_0.5(HPO₃)₂?H₂O ( 1 ), incorporating a tetradentate organic ligand was synthesized under hydro(solvo)thermal conditions and structurally characterized by single‐crystal X‐ray diffraction. Compound 1 is the first example of inorganic zincophosphite chains being interlinked through 1,2,4,5‐tetrakis(imidazol‐1‐ylmethyl)benzene to form a tubular porous framework with unusual organic–inorganic hybrid channels. The thermal and chemical stabilities, high capacity for CO₂ adsorption compared to that for N₂ adsorption, and interesting optical properties of LED devices fabricated using this compound were also studied.     

Tuning the Magnetization Dynamic Properties of Nd⋅⋅⋅Fe and Nd⋅⋅⋅Co Single‐Molecular Magnets by Introducing 3 d–4 f Magnetic Interactions

By using paramagnetic [Fe(CN)₆]^3? anions in place of diamagnetic [Co(CN)₆]^3? anions, two field‐induced mononuclear single‐molecular magnets, [Nd(18‐crown‐6)(H₂O)₄][Co(CN)₆] ? 2 H₂O ( 1 ) and [Nd(18‐crown‐6)(H₂O)₄][Fe(CN)₆] ? 2 H₂O ( 2 ), have been synthesized and characterized. Single‐crystal X‐ray diffraction analysis revealed that compounds 1 and 2 were ionic complexes. The Nd^III ions were located inside the cavities of the 18‐crown‐6 ligands and were each bound by four water molecules on either side of the crown ether. Magnetic investigations showed that these compounds were both field‐induced single‐molecular magnets. By comparing the slow relaxation behaviors of compounds 1 and 2 , we found significant differences between the direct and Raman processes for these two complexes, with a stronger direct process in compound 2 at low temperatures. Complete active space self‐consistent field (CASSCF) calculations were also performed on two [Nd(18‐crown‐6)(H₂O)₄]³⁺ fragments of compounds 1 and 2 . Ab initio calculations showed that the magnetic anisotropies of the Nd^III centers in complexes 1 and 2 were similar to each other, which indicated that the difference in relaxation behavior was not owing to the magnetic anisotropy of Nd^III. Our analysis showed that the magnetic interaction between the Nd^III ion and the low‐spin Fe^III ion in complex 2 played an important role in enhancing the direct process and suppressing the Raman process of the single‐molecular magnet.     

High‐Pressure Synthesis of Metal–Inorganic Frameworks Hf4N20⋅N2, WN8⋅N2, and Os5N28⋅3 N2 with Polymeric Nitrogen Linkers

Polynitrides are intrinsically thermodynamically unstable at ambient conditions and require peculiar synthetic approaches. Now, a one‐step synthesis of metal–inorganic frameworks Hf₄N₂₀?N₂, WN₈?N₂, and Os₅N₂₈?3 N₂ via direct reactions between elements in a diamond anvil cell at pressures exceeding 100 GPa is reported. The porous frameworks (Hf₄N₂₀, WN₈, and Os₅N₂₈) are built from transition‐metal atoms linked either by polymeric polydiazenediyl (polyacetylene‐like) nitrogen chains or through dinitrogen units. Triply bound dinitrogen molecules occupy channels of these frameworks. Owing to conjugated polydiazenediyl chains, these compounds exhibit metallic properties. The high‐pressure reaction between Hf and N₂ also leads to a non‐centrosymmetric polynitride Hf₂N₁₁ that features double‐helix catena‐poly[tetraz‐1‐ene‐1,4‐diyl] nitrogen chains [?N?N?N=N?]_∞.     

Electroactive Benzothiazole Hydrazones and Their [Mo6O19]2− Derivatives: Promising Building Blocks for Conducting Molecular Materials

The electroactive benzothiazole hydrazone AMBTH–H₂, a new member of the 2,2′‐azino‐bis(N‐alkylbenzothiazole) family, was synthesised in a five‐step procedure and characterised by using X‐ray diffraction along with two intermediates and the N‐methylbenzothiazole hydrazone MBTH–H₂. Both AMBTH–H₂ and MBTH–H₂ were coupled to [Mo₆O₁₉]^2? in acetonitrile in the presence of dicyclohexylcarbodiimide and dimethylaminopyridine to give two new diazoalkane–hexamolybdates, which were isolated as tetrabutylammonium salts and characterised by using IR, UV/Vis and NMR spectroscopies, cyclic voltammetry and, for one of them, X‐ray diffraction. The packing arrangement molecules in crystals of AMBTH–H₂, the redox features of the AMBTH–hexamolybdate hybrid together with a good electronic communication between the organic π system and the molybdenum centres make these compounds very promising blocks for the synthesis of conducting molecular materials.     

Sb2Se3‐Sensitized Inorganic–Organic Heterojunction Solar Cells Fabricated Using a Single‐Source Precursor

The photovoltaic performance of Sb₂Se₃‐sensitized heterojunction solar cells, which were fabricated by a simple deposition of Sb₂Se₃ on mesoporous TiO₂ by an approach that features multiple cycles of spin coating with a single‐source precursor solution and thermal decomposition, is reported. Poly[2,6‐(4,4‐bis(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b;3,4‐b′]dithiophene)‐alt‐4,7(2,1,3‐benzothioadiazole)] was used as the hole‐transporting material. The most efficient cell exhibited a short‐circuit current density of 22.3 mA cm^?2, an open‐circuit voltage of 304.5 mV, and a fill factor of 47.2 %, yielding a power conversion efficiency of 3.21 % under standard test conditions (irradiation of 1000 W m^?2, air mass=1.5 G). The results of this study imply that the developed approach has a high potential as a simple and effective route for the fabrication of efficient and inexpensive solar cells.     

Novel hybrid transition metal complexes of diaquabis(acetylacetonato‐κ2o,o′)[nickel(II)/zinc (II)] as solid metal–organic precursors: Synthesis,properties and magnetic response

A series of hybrid hetero bimetallic metal–organic frameworks, as solid metal–organic precursors, have been prepared via a conventional hydrothermal method. Herein, we report a facile approach for the synthesis of novel crystalline organic–inorganic hybrid compounds of diaquabis(acetylacetonato)[nickel(II)/zinc(II)] in the presence of varying mole ratios of Ni(II)/Zn(II) mixed metal ions. C₁₀H₁₈O₆Ni₀.₇Zn₀.₃ (N₀.₇Z₀.₃AA.2H₂O) as an instance of the series has been investigated through detailed characterization. The crystal is composed of N₀.₇Z₀.₃AA units and two coordinated water molecules to form a monoclinic structure with space group P21/c. All the solid‐state structures have the metals in octahedral environments forming six‐membered chelate rings. The unit cell dimensions were obtained using single‐crystal X‐ray diffraction. Thermogravimetric analysis reveals that the hybrid compounds can be considered as suitable precursors for the synthesis of oxides via metal–organic chemical vapour deposition. At room temperature, all crystals clearly exhibit paramagnetic behaviour. Besides varying molar ratios of hybrid, the transition point of magnetic behaviour occurs at Ni critical concentration of around 10% in the hybrid. In addition, the magnetic susceptibility increases with increasing Ni content in the compounds.     

Synthesis,Structure and Photoluminescent Properties of [C6N2H14][Nd2(C2O4)2(SO4)2(H2O)4]·H2O,a New Organically Templated Neodymium(III) Oxalate‐sulfate

An organically templated neodymium oxalate–sulfate [C₆N₂H₁₄][Nd₂(C₂O₄)₂(SO₄)₂(H₂O)₄]·H₂O ( 1 ) has been synthesized under hydrothermal conditions and structurally characterized by single‐crystal X‐ray diffraction analysis. In 1 , the neodymium(III) ions are interconnected through oxalate and sulfate groups to form a neodymium oxalate–sulfate hybrid structure. A luminescence spectrum of 1 was recorded, and the luminescence decay time was also measured.     

[C6H14N]PbBr3: An ABX3‐Type Semiconducting Perovskite Hybrid with Above‐Room‐Temperature Phase Transition

Organic–inorganic hybrid perovskites, with the formula ABX₃ (A=organic cation, B=metal cation, and X=halide; for example, CH₃NH₃PbI₃), have diverse and intriguing physical properties, such as semiconduction, phase transitions, and optical properties. Herein, a new ABX₃‐type semiconducting perovskite‐like hybrid, (hexamethyleneimine)PbBr₃ ( 1 ), consisting of one‐dimensional inorganic frameworks and cyclic organic cations, is reported. Notably, the inorganic moiety of 1 adopts a perovskite‐like architecture and forms infinite columns composed of face‐sharing PbBr₆ octahedra. Strikingly, the organic cation exhibits a highly flexible molecular configuration, which triggers an above‐room‐temperature phase transition, at T_c=338.8 K; this is confirmed by differential scanning calorimetry (DSC), specific heat capacity (C_p), and dielectric measurements. Further structural analysis reveals that the phase transition originates from the molecular configurational distortion of the organic cations coupled with small‐angle reorientation of the PbBr₆ octahedra inside the inorganic components. Moreover, temperature‐dependent conductivity and UV/Vis absorption measurements reveal that 1 also displays semiconducting behavior below T_c. It is believed that this work will pave a potential way to design multifeatured perovskite hybrids by utilizing cyclic organic amines.     

三维超分子配合物[Co2(Dpq)2(btec)(H2O)6]•2H2O的水热合成、晶体结构和电化学性质

以1,2,4,5-均苯四羧酸(btec)和二-吡啶-(3,2-d:2,3'-f)-二氮萘(Dpq)为混合配体,水热合成了一种三维超分子配合物: [Co2(Dpq)2(btec)(H2O)6]•2H2O (1), 并通过元素分析、红外光谱、热重分析和X-射线衍射法对其结构进行了表征。晶体结构解析结果表明,该配合物属单斜晶系,P21/c 空间群,晶胞参数为：a=0.8978(5)nm, b= 2.9822(16)nm, c= 0.7058(4)nm, β= 94.199(6)º, V= 1.8848(18)nm3, Z= 2, R1= 0.0350, wR2= 0.0796。该化合物由1,2,4,5-均苯四羧酸中羧基氧原子、二-吡啶-(3,2-d:2,3'-f)-二氮萘的螯合氮原子及水分子中氧原子与中心Co(II)离子配位, 形成六配位的扭曲八面体几何构型。羧酸作为桥连配体连接两个相邻的中心Co(II)离子形成钴配合物的双核单元,双核单元之间通过氢键及π-π堆积作用相互连接构成三维超分子网状结构。电化学实验结果表明,钴配合物修饰碳糊电极(1-CPE)在0.1 M 乙酸-乙酸钠缓冲溶液中电位范围+600 – –300 mV内有一对归属于Co(II)/Co(III) 的氧化还原峰,而且此修饰电极对亚硝酸根的氧化有很好的电催化效果。     

Hydrogels from Amorphous Calcium Carbonate and Polyacrylic Acid: Bio‐Inspired Materials for “Mineral Plastics”

Given increasing environmental issues due to the large usage of non‐biodegradable plastics based on petroleum, new plastic materials, which are economic, environmentally friendly, and recyclable are in high demand. One feasible strategy is the bio‐inspired synthesis of mineral‐based hybrid materials. Herein we report a facile route for an amorphous CaCO₃ (ACC)‐based hydrogel consisting of very small ACC nanoparticles physically cross‐linked by poly(acrylic acid). The hydrogel is shapeable, stretchable, and self‐healable. Upon drying, the hydrogel forms free‐standing, rigid, and transparent objects with remarkable mechanical performance. By swelling in water, the material can completely recover the initial hydrogel state. As a matrix, thermochromism can also be easily introduced. The present hybrid hydrogel may represent a new class of plastic materials, the “mineral plastics”.