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Four novel lanthanide(iii)–copper(ii) heterometallic coordination polymers based on six-coordinated Cu centres and square-planar tetranuclear {Ln4} SBUs with sulfate as an auxiliary bridging ligand, namely, [Ln2Cu0.5(2,6-pydc)2(2-pyc)(SO4)(H2O)2]·(H2O) (Ln = Nd 1, Sm 2, Eu 3, Gd 4; 2,6-pydc = pyridine-2,6-dicarboxylate, 2-pyc = pyridine-2-carboxylate), have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Compounds 1–4are isostructural and present a rarely reported binodal (4,6)-connected fscnet with the Cu centre as a four-connected node and the tetranuclear {Ln4} SBUs as six-connected nodes. As far as we know, a fscnet in hetero-Ln–TM coordination polymers has never been reported. This work provides a good example of incorporating {Ln4} SBUs and Cu centres to construct a heterometallic binodal net. Notably, the 2-pyc ligand was in situgenerated by decarboxylation of the 2,6-pydc ligand under hydrothermal conditions. Furthermore, the IR, TGA, PXRD, luminescent and magnetic properties were also investigated. [ABSTRACT FROM AUTHOR]

This paper presents a short review of our recent advances in the design and syntheses of inorganic−organic hybrid functional materials and nanometer-scale metallosupramolecules. Perspectives in these two fields are provided. [ABSTRACT FROM AUTHOR]

A series of group 6 transition metal half-sandwich complexes with 1,1-dichalcogenide ligands have been prepared by the reactions of Cp[sup *]MCI[sub 4] (Cp[sup *] = η[sup 5]-C[sub 5]Me[sub 5]; M = Mo, W) with the potassium salt of 2,2-dicyanoethylene-1,1dithiolate, (KS)[sub 2]C=C(CN)[sub 2] (K[sub 2]-i-mnt), or the analogous seleno compound, (KSe)[sub 2]C=C(CN)[sub 2] (K[sub 2]-i-mas). The reaction of Cp[sup *]MCI[sub 4] with (KS)[sub 2]C=C(CN)[sub 2] in a 1:3 molar ratio in CH[sub 3]CN gave rise to K[Cp[sup *]M{S[sub 2]C=C(CN)[sub 2]}[sub 2]] (M = Mo, 1a, 74%; M = W, 2a, 46%). Under the same conditions, the reaction of Cp[sup *]MoCl[sub 4] with 3 equiv of (KSe)[sub 2]C= C(CN)[sub 2] afforded K[Cp[sup *]Mo{ Se[sub 2]C=C(CN)[sub 2]}[sub 2]] (3a) and K[Cp[sup *]Mo{Se[sub 2]C=C(CN)[sub 2]}{Se(Se[sub 2])C=C(CN)2}] (4)in respective yields of 45% and 25%. Cation exchange reactions of 1a, 2a, and 3a with Et[sub 4]NBr resulted in isolation of (Et[sub 4]N)[Cp[sup *]Mo{S[sub 2]C=C(CN)[sub 2]}[sub 2]] (1b), (Et[sub 4]N)[Cp[sup *]W{S[sub 2]C=C(CN)[sub 2]}[sub 2]] (2b), and (Et[sub 4]N)[Cp[sup *]Mo{Se[sub 2]C=C(CN)[sub 2]}[sub 2]] (3b), respectively. Complex 4 crystallized with one THF and one CH[sub 3]CN molecule as a three-dimensional network structure. inspection of the reaction of Cp[sub *]WCI[sub 4] with (KSe)[sub 2]C=C(CN)[sub 2] by ESI-MS revealed the existence of three species in CH[sub 3]CN, [Cp[sup *]W{Se[sub 2]C=C(CN)[sub 2]}[sub 2].] , [Cp[sup *]W{Se[sub 2]C==C(CN)[sub 2]}{Se(Se[sub 2])C=C(CN)[sub 2]}], and [Cp[sup *]W{Se(Se[sub 2])C=C(CN)[sub 2]}[sub 2][sup -], of which [Cp[sup *]W{Se[sub 2]C=C(CN)[sub 2]}{Se(Se[sub 2])C=C(CN)[sub 2]}] (5) was isolated as the main product. Treatment of 2a with ¼ equiv of S[sub 8] in refluxing THF resulted in sulfur insertion and gave rise to K[Cp[sup *]W{S[sub 2]C=C(CN)[sub 2]}{S(S[sub 2])C= C(CN)[sub 2]}] (6), which crystallized with two THF molecules forming a three-dimensional network structure. 6 can also be... [ABSTRACT FROM AUTHOR]

Presents the synthesis of six (6) polymeric copper(II)-lanthanide(III) complexes by the hydrothermal reactions of Ln[sub 2]O[sub 3] (Ln = erbium, gadolinium, samarium), pyridine-2,5-dicarboxylic acid (H[sub 2]pydc and copper(II) reagents. Induction of different structures of the polymeric complexes by the different forms of copper(II) reagents; Temperature-dependent magnetic susceptibilities for 2, 4 and 5 complexes.

Abstract: Ba0.55Sr0.45TiO3 (BST) precursors were synthesized via a polyvinyl alcohol (PVA) modified sol-precipitation route. And the obtained precursors were then calcined in air at temperatures ranging from 400 to 800 °C. The formation mechanism of BST phase was investigated using X-ray diffraction (XRD), while the effect of PVA on the particle morphology of the BST phase was studied by using scanning electron microscopy (SEM). The results show that the introduction of PVA significantly affects the morphology of the BST powders. High purity nanocrystalline powders were synthesized by calcination of the BST precursors encapsulated by PVA gel, with narrow particle distribution (30–80 nm) and being nearly free of agglomeration. While, large particles (40–170 nm) with evident agglomeration were obtained from the solution without PVA. [Copyright &y& Elsevier]

A unique noninterpenetrated 2D bilayer cobalt(II)-organic framework, [{Co(dpe)(NO[sub 2]-BDC)}·0.5(dpe)],·nH[sub 2]O (1), possessing nanoscale rectangular channels that clathrate large organic molecules, has been hydrothermally synthesized by reaction of cobalt(II) salt with 5-nitro-1,3-benzenedicarboxylic acid (NO[sub 2]-H[sub 2]BDC) and 1,2-bis(4-pyridyl)ethylene (dpe). [ABSTRACT FROM AUTHOR]

Details the preparation of the polymeric silver(I) thiolate ligands from the controlled assembling reactions of silver chloride and 2-mercaptopyridine. X-ray diffraction and analysis; One-dimensional chain structure; Three-dimensional network structure; Coordination geometry; Sulfur atom of the thiolate ligand.

High-performance bi-functional materials are in urgent demand for the next-generation integrated optical devices. In this work, we successfully synthesized the first tricyanomelaminate with bi-functional optical responses, namely Cs3C6N9·H2O (I), from its analogue Na3C6N9·3H2O by a facile ion exchange method. In contrast to Na3C6N9·3H2O, I realizes an optimal arrangement of π-conjugated (C6N9)3− anion groups in its crystal structure. As a result, the second-order nonlinear optical (NLO) response is greatly enhanced from nearly zero of Na3C6N9·3H2O to ∼9.8 × KH2PO4 of I. Furthermore, I exhibits a giant linear optical anisotropic response (i.e. birefringence) of 0.52 at the wavelength of 550 nm. Both responses are almost the largest among the inorganic compounds of π-conjugated rings, which indicates that I has great potential as a bi-functional optical crystal. Structural and theoretical analyses reveal the microscopic origin of excellent optical properties. This work would attract a lot of interest to the persistently neglected potential of tricyanomelaminates as linear optical and NLO crystals. [ABSTRACT FROM AUTHOR]

With the help of the ligand-oriented method, we have successfully embedded independent copper-based units into the indium-organic framework system for the first time, in which the Cu4I4 clusters and In3O(CO2)6 clusters coexist. This heterometallic cluster-based framework InOF-8 has a large porosity with extra-open channels along the c-axis, and its sorption capacity has also been investigated. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs), also known as coordination polymers (CPs), are crystalline materials constructed from metal ions or clusters bridged by organic ligands to form one-, two-, or three-dimensional infinite networks. In contrast with the prolific production of MOFs based on rigid ligands (RL-MOFs), the design, syntheses and applications of MOFs based on flexible ligands (FL-MOFs) are somewhat overlooked. Although sacrificing a measure of control, the use of flexible ligands may provide unique opportunities to obtain novel crystalline framework materials exhibiting desirable attributes. In this review, emphasis has been placed on the design and the structural diversity of FL-MOFs. Homochiral FL-MOFs and dynamic frameworks induced by flexible ligands are also briefly outlined. An overview is also shown for the applications of FL-MOFs as platforms for gas adsorption, heterogeneous catalysis, proton conduction etc. [ABSTRACT FROM AUTHOR]

A series of novel lanthanide coordination polymers constructed from organic pyridine-2,6-dicarboxylate (2,6-pydc) and inorganic sulfate, namely, [Eu3(2,6-pydc)3(2,6-Hpydc)(SO4)(H2O)3·(H2O)3] (1), [Ln2(2,6-pydc)2(SO4)(H2O)2·(H2O)2] (Ln = Ce (2); Ln = Pr (3); Ln = Nd (4); Ln = Sm (5)), and [Ce5(2,6-pydc)6(SO4)2(H2O)3·(Me2NH2)] (6), have been synthesized under hydrothermal conditions. X-ray crystal structure analyses reveal that these compounds have a rich structural chemistry. Compound 1presents a four-connected two-dimensional (2D) network based on hexanuclear {Eu6} secondary building units (SBUs). The 2D layers are further linked into a three-dimensional (3D) supramolecular framework via strong π−π stacking interactions of the pyridyl rings. Compounds 2−5are isostructural and adopt uninodal six-connected 3D framework of pcutopology constructed from square-planar tetranuclear {Ln4} SBUs. Of particular interest is that compound 6exhibits a protonated (Me2NH2)뗩ꦕꭞ binodal (4,6)-connected 3D anionic framework with (42510728)(4254) topology, when the Ce(3) monomer and the planar tetranuclear {Ce4} SBUs are regarded as four-connected and six-connected nodes, respectively. Notably, sulfate serves as an auxiliary supporting bridge to strengthen the {Ln4} or {Ln6} SBUs in these compounds. Compound 1displays intense red luminescence and exhibits the characteristic transition of the Eu3誉. The magnetic properties of 1, 4, and 5reveal the weak antiferromagnetic characters. Furthermore, infrared (IR), thermogravimetric analysis (TGA), elemental analyses (EA), and powder X-ray diffraction (PXRD) properties of these compounds are also studied. [ABSTRACT FROM AUTHOR]

A three-dimensional complex, [Mn[sub 3](4-aba)[sub 6]][sub n] (1) (4-Haba = 4-aminobenzoic acid), consisting of manganese(Il) chains and 4-aba bridging ligands, has been synthesized and characterized. Magnetic studies show that the compound behaves as a threedimensional metamagnet built of homometallic ferrimagnetic chains. The required noncompensation in spin moments is achieved by alternating interactions in an AF-AF-F sequence (AF = antiferromagnetic; F = ferromagnetic) by considering intrachain magnetic interactions. [ABSTRACT FROM AUTHOR]

Facile preparation of low-cost electrocatalysts for efficient oxygen evolution reaction (OER) remains a big challenge. Herein, a novel strategy for ultrafast (20 s) transformation of bulk metal–organic frameworks (MOFs) into ultrathin metal oxyhydroxide nanosheets for efficient OER has been developed. For two isomeric MOFs (FJI-H25Fe and FJI-H25FeCo), only the metastable FJI-H25FeCo bulk can immediately transform into FeCo-oxyhydroxides nanosheets through electric-field assisted hydrolysis. The potential evolution process from MOF bulk to FeCo-oxyhydroxides nanosheets has been investigated in detail. The as-made nanosheets exhibit excellent OER performances, showing an extremely low overpotential of 231 mV at the current density of 10 mAcm-2, a relatively small Tafel slope of 42 mVdec-1, and long-term durability of at least 30 h. This work not only provides a novel strategy for facile preparation of low-cost and efficient OER electrocatalysts, but also represents a new way for preparation of metal oxyhydroxides nanosheets with good crystallinity and morphology, and a fresh method for mild synthesis of nanosized derivatives from MOF materials. [ABSTRACT FROM AUTHOR]

By employing a tricarboxylate ligand 1-(4-carboxybenzyl)-1H-pyrazole-3,5-dicarboxylic acid (H3L), four lanthanide metal-organic frameworks (Ln-MOFs) formulated as {[LnL(H2O)2]·H2O}n (Ln = Eu, 1; Gd, 2; Tb, 3; Dy, 4) have been prepared under hydrothermal conditions. Single-crystal X-ray analyses reveal that compounds 1-4 are isomorphous and exhibit a three-dimensional network structure featuring a one-dimensional rectangular channel with a size of ca. 7.8 Å × 12.1 Å along the b axis. The framework shows strong stabilities toward high temperature, humid air, water, as well as acid/base environments. Efficient ligand-sensitized characteristic luminescence can be observed in the visible region for Eu- and Tb-based compounds. Detailed property investigation shows that TbL is a promising multifunctional material, which can quantitatively detect Fe(III) ions in the solution mixtures of Fe(II)/Fe(III), selectively adsorb CO2 over CH4, and be applied as catalysts in cyclization reaction with epoxides and CO2. [ABSTRACT FROM AUTHOR]

Employing a rational design strategy to construct porous metal-organic frameworks (MOFs) with predictable structures for specific applications still remains one of the most compelling challenges. Here, a novel two-dimensional (2D) bilayer (FJI-H16) based on Zn/Cd heterometal clusters has been constructed throughout a heterometal strategy, further introducing pillar ligands with different sizes and flexibilities that expand such 2D bilayer structures into two novel three-dimensional (3D) frameworks (FJI-H17, FJI-H18), in which both the pore size and flexibility of the new-formed 3D frameworks can be tuned. Further gas adsorption research indicates that the less porous FJI-H16has the highest H2 adsorption, while the very porous FJI-H17 has the highest CO2 adsorption. The relationship between gas adsorption properties and pore characteristics also has been investigated, which will provide a potential strategy that can improve gas adsorption in designing porous MOFs. [ABSTRACT FROM AUTHOR]

We herein present a rarely seen (3,4)-connected non-interpenetrated anionic uranium-organic framework with tbo topology (FJI–H-U1), which is constructed from two kinds of ultralarge nanocages. More importantly, FJI–H-U1 can selectively adsorb positively charged organic dyes Ethyl Violet, Janus Green B, and Rhodamine B over the anionic organic dye Methyl Orange due to the nature of its anionic framework. [ABSTRACT FROM AUTHOR]

Ligands with flexible conformations add to the structural diversity of metal-organic frameworks but, at the same time, pose a challenge to structural design and prediction. Representative examples include Zr-tetracarbox-ylate-based MOFs, which afford assorted structures for a wide range of applications, but also complicate the structural control. Herein, we systematically studied the formation mechanism of a series of (4,8)-connected Zr-tetracarbox-ylate-based MOFs by altering the substituents on different positions of the organic linkers. Different ligand rotamers give rise to three types of structures with flu, scu, and csq topologies. A combination of experiment and molecular simulation indicate that the steric hindrance of the substituents at different positions dictates the resulting MOF structures. Additionally, the controllable formation of different structures was successfully implemented by a combination of linkers with different steric effects at specific positions. [ABSTRACT FROM AUTHOR]

The incommensurate (IC) behaviors of ferroelectrics have been widely investigated in inorganic oxides as an exciting branch for aperiodic materials, whereas it still remains a great challenge to achieve such intriguing effects in organic systems. Here, we present that successive ordering of dynamic dipoles in an organic molecular ferroelectric, N-isopropylbenzylaminium trichloroacetate (1), enables unusual incommensurately modulated structures between its paraelectric phase and ferroelectric phase. In particular, 1 exhibits three distinct IC states coupling with a long-range ordering modulation. That is, the incommensurately modulated lattice is ~7 times as large as its periodic prototype, and the IC structure is well solved using a (3 + 1)D superspace group with the modulated wavevector q = (0, 0, 0.1589). To the best of our knowledge, 1 is the first organic ferroelectric showing such a long-range ordering IC structural modulation. In addition, structural analyses reveal that slowing down dynamic motions of anionic moieties accounts for its modulation behaviors, which also results in dramatic reorientation of dipolar moments and concrete ferroelectric polarization of 1 (~0.65 µC/cm²). The combination of unique IC structural modulations and ferroelectricity makes 1 a potential candidate for the assembly of an artificially modulated lattice, which will allow for a deep understanding of the underlying chemistry and physics of aperiodic materials. [ABSTRACT FROM AUTHOR]

We have designed and synthesized a series of two-dimensional materials featuring with a (3,6)-connected kgd layer, in which an unprecedented anionic Cu6I7- cluster was first trapped through a cation-induced synthetic strategy. The emission colors of these cluster-based luminophores gradually shift from blue to yellow as the monovalent cations (Li+, Na+, NH4+, K+, TEA+) located between the neighboring layers changed. SCXRD analyses discover that the variation of the emission may be attributed to the transformation of the hourglass-shaped Cu6I7- cluster. The bright, tunable, and broad luminescent emissions make them promising candidates as phosphors for light-emitting diodes (LEDs). Particularly, compound 1-TEA emitting intensive yellow light with high luminescence quantum efficiency (QY = 79.9%) shows extremely high thermal, pH, organic solvent, and mechanical photostabilities. By employing it as a yellow phosphor, we fabricate a series of white lighting materials with high color rendering index (CRI). [ABSTRACT FROM AUTHOR]

All-inorganic cesium lead halide perovskite (CsPbX3, X = Cl, Br, and I) quantum dots (QDs), possessing high photoluminescence quantum yields and tunable color output, have recently been endowed great promise for high-performance solar cells and light-emitting diodes (LEDs). Although moisture stability has been greatly improved through separating QDs with a SiO2 shell, the practical applications of CsPbX3 QDs are severely restricted by their poor thermal stability, which is associated with the intrinsically low formation energies of perovskite lattices. In this regard, enhancing the formation energies of perovskite lattices of CsPbX3 QDs holds great promise in getting to the root of their poor thermal stability, which hitherto remains untouched. Herein, we demonstrate an effective strategy through Mn2+ substitution to fundamentally stabilize perovskite lattices of CsPbX3 QDs even at high temperatures up to 200 °C under ambient air conditions. We employ first-principle calculations to confirm that the significantly improved thermal stability and optical performance of CsPbX3:Mn2+ QDs arise primarily from the enhanced formation energy due to the successful doping of Mn2+ in CsPbX3 QDs. Benefiting from such an effective substitution strategy, these Mn2+-doped CsPbX3 QDs can function well as efficient light emitters toward the fabrication of high-performance perovskite LEDs. [ABSTRACT FROM AUTHOR]

Developing superior deep-ultraviolet (deep-UV) nonlinear optical (NLO) materials is a great challenge because of the contradiction between deep-UV transparency and enhanced second harmonic generation (SHG), especially for deep-UV NLO phosphates in which the constituent P-O groups have relatively small microscopic SHG coefficients. Here we report a new noncentrosymmetric phosphate Cs2LiPO4 (I), whose crystal structure consists of [LiPO4]∞ layered structural units with a novel honeycomb-like topology. As compared with the benchmark deep-UV NLO material KBe2BO3F2, I is beryllium-free, and it is relatively easy to grow its large single crystals because of its congruent melting. Furthermore, it not only is deep-UV transparent but also exhibits an unexpectedly enhanced SHG response of 1.8 × KH2PO4 that hits a new high in deep-UV NLO phosphates. These results demonstrate that I satisfies the key requirements of being a promising deep-UV NLO candidate. Theory calculations and structural analysis reveal that the enhanced SHG response can be attributed to the honeycomb-like topological structure, which endows the constituent [PO4]3- monomers of I with an aligned arrangement and as a result a favorable superposition of their microscopic SHG coefficients. These findings may provide useful insights into the development of both deep-UV NLO materials and honeycomb-like topological structures. [ABSTRACT FROM AUTHOR]

A novel tripodal ligand L that only has a syn conformer has been designed and synthesized. Different Ag3L2 metallocages can be effectively assembled from such concave ligands and different Ag(I) salts. ESI-MS research indicates that a Ag3L2 metallocage can encapsulate different anions selectively, in which the encapsulation capacity is as follows: NO3- > ClO4- > SO42-; moreover, selective encapsulation of NO3- from a mixture of NO3- and ClO4- has been observed. [ABSTRACT FROM AUTHOR]

Herein, 15 lanthanide coordination complexes based on three di-, tri-, and tetra-carboxylic ligands with imidazolyl groups have been solvothermally designed, synthesized, and characterized. All the complexes exhibit high thermal stabilities and can remain stable in the open air more than 7 days. Luminescent spectra of Eu3+ and Tb3+ complexes at room temperature indicate that the three carboxylic ligands H2L¹, H3L², and H4L³ are promising potential light sensitizers for lanthanide ions based on their suitable triplet energy levels. Luminescent lifetimes and quantum yields of these compounds were further measured and compared. The correlations between their structural features and photophysical properties are discussed in detail. [ABSTRACT FROM AUTHOR]

A beryllium-free deep-ultraviolet (deep- UV) nonlinear optical (NLO) material K3Ba3Li2Al4B60 2oF is developed mainly by the element substitution of Be for Al and Li from Sr2Be2B2O7 that was considered as one of the most promising deep-UV NLO materials. K3Ba3Li2Al4B60 2 oF preserves the structural merits of Sr2Be2B2O7 and thus exhibits no layering growth tendency and possesses the optical properties required for deep-UV NLO applications, including deep-UV transparency, phasematchability, and sufficiently large second-harmonic generation (1.5 X KH2PO4). Furthermore, it overcomes the structural instability problem of Sr2Be2B2O7, which is confirmed by the obtainment of large single crystals and phonon dispersion calculations. These attributes make it very attractive for next-generation deep-UV NLO materials. The substitution of Be for Al and Li in beryllium borates provides a new opportunity to design berylliumfree deep-UV NLO materials with good performance. [ABSTRACT FROM AUTHOR]

To switch bulk nonlinear optical (NLO) effects represents an exciting new branch of NLO material science, whereas it remains a great challenge to achieve high contrast for "on/off" of quadratic NLO effects in crystalline materials. Here, we report the supereminent NLO-switching behaviors of a single-component plastic crystal, 2-(hydroxymethyl)-2-nitro-l,3-propanediol (l), which shows a record high contrast of at least 庤150, exceeding all the known crystalline switches. Such a breakthrough is clearly elucidated from the slowing down of highly isotropic molecular motions during plastic-torigid transition. The deep understanding of its intrinsic plasticity and superior NLO property allows the construction of a feasible switching mechanism. As a unique class of substances with short-range disorder embedded in long-range ordered crystalline lattice, plastic crystals enable response to external stimuli and fulfill specific photoelectric functions, which open a newly conceptual avenue for the designing of new functional materials. [ABSTRACT FROM AUTHOR]

A series of hybrids of nitrogen-dopedgraphitic porous carbon andcarbon nanotubes (NGPC/NCNTs) are readily prepared in a stepwise mannerby using a typical metal–organic framework (MOF-5) and ureaas the carbon and nitrogen precursors, and nickel as the graphitizationcatalyst, respectively. These NGPC/NCNTs hybrids have demonstratedprominent catalytic activities toward oxygen reduction reaction (ORR)in alkaline medium. Compared to the benchmark Pt/C catalyst, the optimizedNGPC/NCNT-900 (annealed at 900 °C) exhibits superior catalyticactivity, durability and methanol tolerance, which makes it one ofthe best ORR electrocatalysts derived from MOFs. The promising propertiesin NGPC/NCNT-900 are mainly attributed to synergistic contributionsof its unique hybrid structure, rich nitrogen doping, high graphiticdegree, and large surface area. This attractive route for the preparationof NGPC/NCNTs holds promise for general use of a great number of availableand yet rapidly growing MOFs in constructing high-performance carbon-basedORR electrocatalysts. [ABSTRACT FROM AUTHOR]

Utilizing presynthesized large Na2Ni12Ln2 clusters (Ln = Dy and Tb) supported by calixarene as molecular building blocks (MBBs), we have obtained a series of cationic trigonal prismatic heterometallic organic nanocages (HMONCs) with tunable sizes through a stepwise method. Specially, in each structure of the HMONCs, three linear dicarboxylate linkers substitute the peripheral coordinated acetate ligands of two Na2Ni12Ln2 clusters to form an unprecedented Na4Ni24Ln4 HMONC through a M2L3 condensation. Moreover, magnetic study reveals that the Na2Ni12Dy2 core retains its slow magnetic relaxation behavior. Gas sorption behaviors of these HMONCs were also studied. To the best of our knowledge, these HMONCs built from large heterotrimetallic Na2Ni12Ln2 MBBs, which are based on smaller Ni4-calix ones, have not been reported in any other cages to date. In addition, this research also provides a new strategy for the design and construction of HMONCs with predictable structures and functional properties. [ABSTRACT FROM AUTHOR]

A new beryllium-free borate Rb3Al3B3O10F has been synthesized and characterized by single-crystal X-ray diffraction. It features a framework structure consisting of alveolate [Al3(BO3)3OF]∞ layers tightly bound via Al-O and Al-F bridged bonds, with the in-layer [BO3]3- groups in nearly coplanar and aligned arrangement. This compound is transparent down to 200 nm and is phase-matchable with a powder second-harmonic generation efficiency of 1.2 times that of KH3PO4. Remarkably, it exhibits a strong interlayer bonding which is about one order larger than that of the benchmark KBe2BO3F2, thus no layering tendency was observed during the crystal growth. In addition, it is nonhygroscopic and thermally stable up to ∼1462 K. These attributes make Rb3Al3B3O10F a promising nonlinear optical crystal in the deep-ultraviolet region. First-principles calculations, combined with the anionic group theory, were adopted to rationalize the optical properties. [ABSTRACT FROM AUTHOR]

Twonovel thiacalix[4]arene-based high-nuclearity cobalt clusters,[Na2Co24(BTC4A)6(PO4)6(HCOO)6(DMC)2(DMF)2(dma)4]·5DMF·9CH3OH (denoted as Na2@Co24, 1) and [KCo24(BTC4A)6(PO4)6(Cl)2(HCOO)4(DMF)8][KCo24(BTC4A)6(PO4)6(Cl)2(HCOO)6(DMF)4(CH3OH)2]·8DMF·23CH3OH (denotedas K@Co24, 2) (H4BTC4A = p-tert-butylthiacalix[4]arene, DMC = N,N'-dimethylcarbamic acid anion, dma = dimethylamine),have been solvothermally prepared and structurally characterized. Compounds 1and 2are each capped by sixCo4-BTC4A molecular building blocks (MBBs) and six phosphatelinkers and other different auxiliary anions, possessing an eicositetranuclearCo24core templated by alkali-metal cations. In essence, compound 1is templated by two Na+cationswith an attractive interaction in the center of the core, while 2is templated by one K+with a larger radius. Such differences "convert" an oval-shaped Co24disklike core in 1to a circular core in 2. Interestingly, 2contains both anionic and cationicKCo24cores, representing the largest cobalt aggregatesalt reported, to the best of our knowledge. In addition, magneticmeasurements of 1and 2were investigated, revealing the existence of antiferromagnetic interactions betweenthe magnetic CoIIcenters. [ABSTRACT FROM AUTHOR]

Two indium--organic framework isomers, namely [Me2NH2][In(BPDC)2](InOF-3)and[MeNH3][In(BPDC)2] (InOF-4), have been solvothermally prepared from a biphenyl-3,3'-dicarboxylate ligand (H2BPDC) with changeable conformation, and feature skeletal frameworks with equivalent chemical formulae. For the 2D close-packing InOF-3, each 3-connected [In(O2CR)4] node connects to 3 others through syn-BPDC² ligands, leading to a 3-connected uninodal layer with a point symbol of {6³}. For the 3D microporous InOF-4, the framework is assembled from [In(O2CR)4] nodes bridged by dicarboxylate ligands in the anti- fashion. Careful examination of the structure shows that InOF-4 is a 4-fold interpenetrating network and topologically adopts a diamond-like 4-connected uninodal net with a point symbol of {66}. More importantly, the theoretical calculations and the experimental single component gas uptake measurements reveal that the 3D porous InOF-4 has a better low pressure gas storage capacity than its 2D framework isomer InOF-3, with a saturated N2 uptake of 168.2 cm³ g at 77 K and H2 uptake capacities of up to 126.5 cm³ g-1 (1.13 wt%) at 77 K and 1.0 bar, and 98.1 cm³ g-1 (0.88 wt%) at 87 K and 1.0 bar. Finally, the IAST calculations show us that both microporous materials have an outstanding low-pressure selectivity between CO2 and N2, probably due to their intrinsic structural characteristics. [ABSTRACT FROM AUTHOR]

It is challenging to explore deep-ultraviolet (deep-UV) nonlinear optical (NLO) materials that can achieve a subtle balance between deep-UV transparency and high NLO activity. Known deep-UV NLO materials are almost exclusively limited to borates, except few newly discovered phosphates despite their small NLO activities. Here we report two asymmetric phosphates, RbBa2(PO3)5 (I) and Rb2Ba3(P2O7)2 (II), which feature [PO3]∞ chains and [P2O7]4- dimers formed by condensation of [PO4]3- units, respectively. Remarkably, I achieves the desired balance, with the shortest deep-UV absorption edge at 163 nm and the largest NLO activity of 1.4 × KDP (KH2PO4) in deep-UV NLO phosphates. According to first-principles calculations, the enhanced macroscopic SHG response of I can be attributed to the [PO3]∞ chains which exhibit significantly larger microscopic SHG coefficients as compared with the [P2O7]4- dimers. [ABSTRACT FROM AUTHOR]

A new noncentrosymmetric borate CsZn2B3O7 was synthesized by the solid-state reaction techniques. The crystals were obtained by flux method and are of block shape without layering tendency. Single-crystal X-ray diffraction analysis reveals that the crystal structure is composed of [Zn2BO5]8 two-dimensional layers that are bridged by [B3O6]3- groups to form a three-dimensional framework with one-dimensional channels occupied by Cs+ cations along the a and c axes. Thermal analysis indicates that CsZn2B3O7 melts incongruently. UV-visible-near-IR diffuse reflectance spectrum gives a short absorption edge at 218 nm. CsZn2B3O7 is phase-matchable, with a powder second-harmonic generation (SHG) efficiency of 1.5 × KDP (KDP, potassium dihydrogen phosphate) at 1064 nm, based on the Kurtz-Perry method. These results show that CsZn2B3O7 may have prospects as a UV nonlinear optical material. Interestingly, the SHG efficiency of CsZn2B3O7 is about twice that of ?-KBe2B3O7, a structurally analogous alkaline and alkaline earth borate. First-principles calculations combined with atom-cutting analysis reveal that the ZnO4 tetrhedral groups in CsZn2B3O7 account for the SHG enhancement. [ABSTRACT FROM AUTHOR]

Self-assembly of Co(II)/Cd(II) with 4,4'-sulfonyldibenzoic acid and bis(4-pyridylmethyl)piperazine has produced 3D interpenetrated and non-interpenetrated polythreading networks with non-trivial linkages. [ABSTRACT FROM AUTHOR]

Four kite-like tetranuclear ZnIILNIII3 (Ln= Gd 1, Tb 2, Dy 3, Ho 4) clusters supported by p-ferf-butylthiacalix[4]arene (H4BTC4A) have been prepared under solvothermal conditions and structurally characterized by single crystal X-ray diffraction and powder X-ray diffraction (PXRD). In the structures of these four complexes, each of them is capped by two tail-to-tail p-ter£-butylthiacalix[4]arene molecules to form a bent sandwich-like unit The photoluminescent analyses reveal that the H4BTC4A is an efficient sensitizer for Tb3+ions in 2. The magnetic properties of complexes 1--4 are also investigated, in which complex 3 exhibits slow magnetization relaxation typical for single molecule magnets. [ABSTRACT FROM AUTHOR]

A series of discrete complexes, [Ni8(BTC4A)2(μ6-CO3)2(μ-CH3COO)4(dma)4]·H2O (1), [Ni8(BTC4A)2(μ6-CO3)2(μ-Cl)2(μ-HCOO)2(dma)4]·2DMF·2CH3CN (2), [Ni8(PTC4A)2 (μ6-CO3)2(μ-CH3COO)4(dma)4]·DMF (3), and [Ni8(PTC4A)2(μ6-CO3)2(μ-OH)(μ-HCOO)3 (dma)4] (4) (p-tert-butylthiacalix[4]arene = H4BTC4A, p-phenylthiacalix[4]arene = H4PTC4A, dma = dimethylamine, and DMF = N,N′-dimethylformamide), have been prepared under solvothermal conditions and structurally characterized by single-crystal X-ray diffraction analyses, powder XRD, and IR spectroscopy. These four complexes are stacked by dumbbell-like building blocks with one chairlike octanuclear-nickel(II) core, which is capped by two thiacalix[4]arene molecules and connected by two in situ generated carbonato anions and different auxiliary anions. This work implied that not only the solvent molecules but also the upper-rim groups of thiacalix[4]arenes have significant effects on the self-assembly of the dumbbell-like building blocks. The magnetic properties of complexes 1-4 were examined, indicating strong antiferromagnetic interactions between the nickel(II) ions in the temperature range of 50-300 K. [ABSTRACT FROM AUTHOR]

A chiral coordination nanotube, [Cd3(BPT)2(H2O)9]∙2H2O (Cd-1; BPT = biphenyl-3,4',5-tricarboxylate), has been synthesized from achiral components and structurally characterized. It consists of homochiral channels based on right-handed helical chains and shows an interdigitated interaction to give a chiral 3D network. The chiral nanotubular framework exhibts dynamic structural transformation upon removal of the guest molecules, and the polarity of this compound induces it to display both ferroelectric and nonlinear-optical properties. [ABSTRACT FROM AUTHOR]

Abstract: Four isostructural lanthanide(III) complexes, [Ln2(HL)2(H2O)4]n·2nH2O (H4L=3,3′,6,6′-tetracarboxyl-2,2′-bipyridine) (Sm (1), Eu (2), Gd (3), Tb (4)), have been synthesized under the hydrothermal condition and characterized by single-crystal X-ray diffractions, powder X-ray diffractions (PXRD), thermal analyses (TGA) and elemental analyses (EA). These four complexes all exhibit 1D chain-like structures containing di-nuclear lanthanide(III) units, which are further linked by hydrogen bonding into 3D supramolecules. To further investigate the properties of the above complexes, the photoluminescent properties of 2 and 4 are also discussed. [Copyright &y& Elsevier]

A novel third-order nonlinear optical (NLO) crystal based on the organic borate carboxylate ester, with formula [Na4(H2O)5][B{O2CCH(O)Ph}2]4(abbreviated as LMBNa), has been prepared in aqueous solution. Single-crystal X-ray diffraction analysis reveals that the boron atom is coordinated with two l-mandelic ligands by alkoxide and carboxylate groups, forming the [B{OOCCH(O)C6H5}]−anion. The sodium cation supports its structural framework of borate anions in the formation of a cross-linked structure. Bulk single crystals of LMBNa were grown from acetonitrile/water by the temperature lowering method. Studies of its third-order NLO properties using a Z-scan technique demonstrate that the LMBNa crystal possesses a strong saturable absorption and the self-focusing effect. Its second molecular hyperpolarizability (γ) at 532 nm is calculated to be (3.9 ± 0.2) × 10−31esu. Furthermore, dielectric experiments reveal that LMBNa has a quite low-dielectric constant (∼3.43) and shows an anisotropy of frequency dependence along the different crystallographic directions. Such dielectric behaviors will favor the application of the LMBNa crystal under the electric field. All the results indicate that LMBNa might be a potential candidate material for the third-order NLO applications. [ABSTRACT FROM AUTHOR]

Two three-dimensional coordination polymers were solvothermally prepared through in situformation of a 2-sulfobenzoic acid ligand from a 2,2′-dithiobisbenzoic acid precursor involving the oxidative cleavage of its disulfide bond. Complex 1shows neb-e topology, while complex 2exhibits a scarcely reported twisting chiral dense 75.9 net. [ABSTRACT FROM AUTHOR]

By using Pd(TFA)2/PCy3 as a catalyst, a broad range of aromatic carboxylic acids, including heteroaromatic carboxylic acids, efficiently underwent decarboxylative coupling with an array of polyfluoroarenes in the presence of stoichiometric amount of silver salts to generate biaryls. Silver salts were adjusted to the reactivity of aromatic carboxylic acids to efficiently suppress the protodecarboxylation and therefore improve decarboxylative cross-couplings. It was established that the palladium complex containing the PCy3 ligand was capable of catalyzing the decarboxylation of electron-rich aromatic carboxylic acids, and silver salts promoted the decarboxylation of both electron-rich and -deficient ones. To explain the two different decarboxylation processes, two possible reaction pathways are proposed, which were further supported by the facts that the stoichiometric arylpalladium complex can directly arylate pentafluorobenzene in the presence of PCy3 and the arylpalladium complex can catalyze the decarboxylative coupling of 2,4-dimethoxybenzoic acid with pentafluorobenzene. The kinetic isotope effect of 4.0 clearly showed that the C-H bond cleavage of polyfluoroarenes is involved in the rate-determining step. [ABSTRACT FROM AUTHOR]

Pd-catalyzed decarboxylative Heck coupling of aromatic carboxylic acids with various olefins is developed using O2as the terminal oxidant. Enhancement of O2pressure leads to improving reaction turnover in this transformation and allows significantly reducing catalyst loading for efficient conversion of electron-rich benzoic acids. A Pd catalyst supported by a carbene ligand enables using electron-deficient benzoic acids as coupling partners. [ABSTRACT FROM AUTHOR]

The reactions of 2,4,6-tri(2-pyridyl)-1,3,5-triazine (tpt) and Ag(I) ions under solvothermal or solvent evaporation conditions yielded three new coordination complexes with the interesting frameworks: [Ag(tpt)(NO3)]n(1), [Ag2(tpt)(NO3)(PPh3)2(H2O)](NO3)·2H2O (2), [Ag8(tpt)4(NO3)4(µ2-CN)2](NO3)2(3) (PPh3= triphenylphosphine). Complex 1crystallizes in a chiral space group P212121, giving a 1D chain and left-handed helical structure which is the first example of metal-tpt complexes with helical chains. Through the π–π interactions and C–HO hydrogen bonding, the 1D chains of 1further form a 3D supramolecular structure. Dinuclear complex 2gives a 3D network viaintramolecular O–HO and C–HO hydrogen bonding, while the octanuclear complex 3affords a 2D framework through weak AgAg interactions and van der Waals force. Complexes 1and 3exhibit high thermal stabilities at 350 and 300 °C, respectively, and both display unusual yellow luminescence in the crystal-state at cryogenic temperature. [ABSTRACT FROM AUTHOR]

The palladium-catalyzed direct arylation of electron-deficient arenes that contain two or more fluorine groups with arylboronic acids was realized. The key to achieving a broad substrate scope with respect to both polyfluorobenzenes and arylboronic acids is the choice of bases depending on acidities of polyfluorobenzenes. [ABSTRACT FROM AUTHOR]

A microporous metal organic framework structure, Zn2(bpdc)2(bpee)—2DMF (DMF; N, N-dimethylformamide), has been synthesized via solvothermal reactions. The compound is a new member of the RPM series (RPM=Rutgers Recyclable Porous Material) that possesses a flexible and recyclable three-dimensional framework containing one-dimensional channels. It exhibits interesting and multifold functionality, including porosity, commensurate absorption for hydrocarbons, high hydrogen binding energy (determined by isosteric heats of hydrogen adsorption and confirmed by van der waals density functional calculations) as a result of multifold binding to aromatic ligands (determined by IR spectroscopy), strong photoluminescence emission, and reversible flourescence quenching properties. [ABSTRACT FROM AUTHOR]

Large-scale pure titanate nanotubes were synthesized through the hydrothermal reaction between TiO2powders and concentrated NaOH under an unexpected high temperature of 240 °C, while it was generally claimed that it is impossible to form nanotubes at temperatures higher than 180 °C. The titanate nanotube was found to be an inevitable intermediate product, which finally transformed into a nanowire upon increasing the hydrothermal treatment duration. It was proven that the successive appearance of nanosheets, nanotubes, and nanowires are three unavoidable kinetic products of the reaction. Increasing the temperature could only accelerate the nanotube−nanowire transformation process but could not affect the sequence of the reaction events. The transformation kinetics from nanotubes to nanowires under different reaction temperatures was studied. Detailed studies indicate that this transformation process was accompanied by a coarsening process induced by both oriented attachment (OA) and Ostwald ripening (OR) mechanisms simultaneously; thereafter, the OA−OR cooperative mechanism was proposed. [ABSTRACT FROM AUTHOR]

A versatile palladium catalyst system was developed to effect the decarboxylative Heck coupling of a variety of arenecarboxylic acids with a wide range of olefins. The key to obtaining the efficient catalyst system is the use of 1-adamatanecarboxylic acid as additive. Alkyl-substituted olefins with coordinating groups were observed to provide significantly improved regioselectivity compared with other alkyl-substituted olefins lacking coordinating groups, and the acetate group of allylic ester was also tolerated in this reaction. [ABSTRACT FROM AUTHOR]

Three d[sup10]-d[sup10] transition-metal complexes with organosulfur ligands, Cu[sub6](btt)6 (1), Cu4(btt)4 (2), and Ag[sub6](bmt)[sub6] ∙ 6THF (3) (Hbtt = 2-benzothiazolethiol, Hbmt = 2-benzimidazolethiol, and THF = tetrahydrofuran), were synthesized and characterized. Complexes 1 and 2 with similar coordination environments are isomers crystallized from the same solvothermal reactions, but they cause great differences in both the structures and luminescent behaviors. The hexanuclear cluster 1 exhibits unusual near-infrared luminescence and high thermal stability, while complex 2 with tetranuclear cores and stronger metal-metal bonds shows an intense red emission like that from complex 3. [ABSTRACT FROM AUTHOR]

A new type of disilver(I) macrocyclic species in solution was synthesized and further adopted as a novel building block for the construction of distinct crystalline structures in a predesigned way. [ABSTRACT FROM AUTHOR]

Exploration into the supramolecular chemistry of p-sulfonatothiacalix[4]arene (TCAS) tetranuclear clusters with methylviologen dihexafluorophosphate (MV(PF6)2) and 4,4′-diaminodiphenyl ether (4,4′-Dadpe) has resulted in three interesting structural motifs: {[MV][Co4(TCAS)(μ4-SO4)(H2O)8]·8H2O}n(1), {[Na(H2O)2][Co4(TCAS)(μ5-SO4)(H2O)7(4,4′-HDadpe)]·6H2O}n(2), and {[MV][Cu4(TCAS)(μ4-SO4)(H2O)4]·9H2O}n(3). In complex 1, the assembly of TCAS tetracobalt(II) clusters driven by multiple hydrogen bonding forms supramolecular helices along three crystallographic axes, while TCAS tetracobalt(II) clusters in complex 2have assembled into a rare head-to-tail chain mediated by sodium ions in the presence of 4,4′-Dadpe. Complex 3features a regular ionic bilayer structure, in which TCAS tetracopper(II) clusters and MV2熫抢 form negative and positive layers, respectively. [ABSTRACT FROM AUTHOR]

A enneanuclear nanocage, [Ni9(HL)6(Pz)6](PzH)3(ClO4)3(H2O)24(1), has been synthesized by coordination-driven face-directed self-assembly of octahedral Ni(II) ions and asymmetric hydrazone ligands with addition of pyrazole in ethanol solution. Compound 1with hexahedral nanocage structure has been characterized by elemental analysis, FT-IR, TGA, ESI-MS, and X-ray diffraction analysis. Furthermore, variable-temperature magnetic studies for compound 1have also been reported. [ABSTRACT FROM AUTHOR]