Showing papers on "Coordination polymer published in 2010"
TL;DR: The high permanent porosity of 1 allows for rapid diffusion of oxygen through the open channels, leading to efficient and reversible quenching of the (3)MLCT phosphorescence, highlighting the opportunity of designing highly porous and luminescent coordination polymers for sensing other important analytes.
Abstract: Phosphorescent cyclometalated iridium tris(2-phenylpyridine) derivatives were designed and incorporated into coordination polymers as tricarboxylate bridging ligands. Three different crystalline coordination polymers were synthesized using a solvothermal technique and were characterized using a variety of methods, including single-crystal X-ray diffraction, PXRD, TGA, IR spectroscopy, gas adsorption measurements, and luminescence measurements. The coordination polymer built from Ir[3-(2-pyridyl)benzoate]3, 1, was found to be highly porous with a nitrogen BET surface area of 764 m2/g, whereas the coordination polymers built from Ir[4-(2-pyridyl)benzoate]3, 2 and 3, were nonporous. The 3MLCT phosphorescence of each of the three coordination polymers was quenched in the presence of O2. However, only 1 showed quick and reversible luminescence quenching by oxygen, whereas 2 and 3 exhibited gradual and irreversible luminescence quenching by oxygen. The high permanent porosity of 1 allows for rapid diffusion of ...
569 citations
TL;DR: The copper(I) halide aggregates represent a versatile family in coordination chemistry and crystal engineering and have been intensively investigated in the last three decades because of their structural and luminescent uniqueness as discussed by the authors.
485 citations
TL;DR: In this paper, a simple and straightforward method combines microwave assisted solvothermal conditions with coordination modulation method to achieve the size-controlled formation of the porous coordination polymer (PCP), [Cu3(btc)2] (where btc represents benzene-1,3,5-tricarboxylate) in the nano/micro regimes.
Abstract: A simple and straightforward method combines microwave-assisted solvothermal conditions with the coordination modulation method to achieve the size-controlled formation of the porous coordination polymer (PCP), [Cu3(btc)2] (where btc represents benzene-1,3,5-tricarboxylate) in the nano/micro regimes. The addition of a monocarboxylic acid modulator to the reaction mixture greatly influenced the morphology of the resulting sample, through competitive coordination interactions during the crystal formation process. By adjusting the concentration of dodecanoic acid additive, we could subtly control the nucleation rate of a [Cu3(btc)2] framework and, thus, the resulting crystal size. Homogeneous nanocrystals of the PCP with sizes ranging from few tenths of nanometers up to few micrometers could be successfully obtained in a controlled manner. X-ray diffractions and gas sorption measurements revealed highly crystalline particles with large pore volumes. Moreover, variations in the sorption profiles could be corr...
434 citations
TL;DR: A new technique for the rapid preparation of porous coordination polymer nanocrystals that combines non-aqueous inverse microemulsion with ultrasonication is presented and a model for particle formation and growth is presented.
Abstract: Porous coordination polymers, in particular flexible porous coordination polymer networks that change their network structure on guest adsorption, have enormous potential in applications involving selective storage, separation and sensing. Despite the expected significant differences in their adsorption properties, porous coordination polymer nanocrystals remain largely unexplored, and there have been no reports about studies on flexible porous coordination polymer nanocrystals, mainly due to a lack of preparation methods. Here, we present a new technique for the rapid preparation of porous coordination polymer nanocrystals that combines non-aqueous inverse microemulsion with ultrasonication. Uniform nanocrystals of {[Zn(ip)(bpy)]}(n) (ip = isophthalate, bpy = 4,4'-bipyridyl; CID-1), a flexible porous coordination polymer, have been prepared by this method and analysed using field-emission scanning electron microscopy, energy-dispersive X-ray analysis, infrared spectroscopy, Raman spectroscopy and X-ray powder diffraction. A model for particle formation and growth is presented and discussed. Adsorption experiments with methanol show that the overall adsorption capacities of nanoparticles and bulk are almost identical, but the shapes of the sorption isotherms differ significantly and the adsorption kinetics increase dramatically.
311 citations
TL;DR: The effective selective sorption of dioxygen and nitric oxide is described by a structurally and electronically dynamic porous coordination polymer built from zinc centres and tetracyanoquinodimethane (TCNQ) as a linker.
Abstract: Porous coordination polymers are materials formed from metal ions that are bridged together by organic linkers and that can combine two seemingly contradictory properties-crystallinity and flexibility. Porous coordination polymers can therefore create highly regular yet dynamic nanoporous domains that are particularly promising for sorption applications. Here, we describe the effective selective sorption of dioxygen and nitric oxide by a structurally and electronically dynamic porous coordination polymer built from zinc centres and tetracyanoquinodimethane (TCNQ) as a linker. In contrast to a variety of other gas molecules (C(2)H(2), Ar, CO(2), N(2) and CO), O(2) and NO are accommodated in its pores. This unprecedented preference arises from the concerted effect of the charge-transfer interaction between TCNQ and these guests, and the switchable gate opening and closing of the pores of the framework. This system provides further insight into the efficient recognition of small gas molecules.
293 citations
TL;DR: Gas sorption experiments and grand canonical Monte Carlo simulations for two isostructural microporous metal azolate frameworks show that even partially exposed uncoordinated nitrogens can effectively increase gas binding affinity and overcome the pore size confinement effect.
Abstract: Gas sorption experiments and grand canonical Monte Carlo simulations for two isostructural microporous metal azolate frameworks show that even partially exposed uncoordinated nitrogens can effectively increase gas binding affinity and overcome the pore size confinement effect.
289 citations
TL;DR: A multifunctional bidimensional mixed-valence copper coordination polymer [Cu2Br(IN)2]n (IN = isonicotinato) has been characterized in crystal phase and isolated on graphite surface as single sheets.
205 citations
TL;DR: Hollow coordination polymer microspheres with microporous shells are formed by a one-pot solvothermal reaction without any additional template, and it is confirmed that the Ostwald ripening mechanism is responsible for the formation of hollow cavities with controllable size.
Abstract: Hollow microspheres with pores in their shells have received much attention owing to their hierarchically porous structures and advanced applications in electrochemical capacitive energy storage, hydrogen storage, drug delivery, sensing, and catalysis. For example, Lou et al. reported that hollow SnO2 nanospheres with nanoporous shells showed high reversible charge capacity and good cycling performance. Zhu et al. investigated the drug-delivery properties of hollow silica spheres with mesoporous shells and found that the hollow microspheres were able to store significantly more molecules with higher release rates than conventional mesoporous silica. Template synthesis is one of the most-used strategies to prepare hierarchically hollow microspheres, especially for pores inside the shells. Braun and co-workers have prepared hollow ZnS microspheres with mesoporous shells using dual templates assembled by lyotropic liquid crystals on the surfaces of silica or polystyrene colloidal templates. Liu et al. have produced organic–inorganic hybrid hollow nanospheres with microwindows on the shells templated by tricopolymer aggregates. The template method is general to prepare hollow microspheres with pores in the shells, but expensive and tedious post-treatment processes, such as solvent extraction, thermal pyrolysis, or chemical etching, and resultant fragile frameworks, limit or even impair its applicability. 3, 4] As a result, it remains an important challenge to develop a convenient and template-free method to prepare hollow microspheres with porous shells. Porous coordination polymers are highly ordered porous multifunctional materials prepared by linking metal ions or metal oxide clusters with multidentate organic ligands without any additional template. Construction of shells of hollow materials with porous coordination polymers is an especially promising approach to design hollow microspheres with porous shells through a template-free method and to endow materials with multifunctionality, such as electric, magnetic, and optical properties. Herein, we report the formation of hollow coordination polymer microspheres with microporous shells by a one-pot solvothermal reaction without any additional template; the shells are constructed of iron-based ferrocenyl coordination polymers. We confirm that the Ostwald ripening mechanism is responsible for the formation of hollow cavities with controllable size. Hollow iron-based ferrocenyl coordination polymer microspheres (Fe-Fc-HCPS) were synthesized by a solvothermal reaction of FeCl3·6H2O with 1,1’-ferrocenedicarboxylic acid (H2FcDC) in N,N-dimethyl formamide (DMF; Figure 1a). The precipitate was collected by centrifugation and washed several times with DMF and CHCl3. The reaction temperature, reaction time, and molar ratio of reactants play important roles in the formation of hollow spherical particles. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and optical microscopy (OPM) were
172 citations
TL;DR: In this article, hierarchical nanostructured coordination polymer Ce(1,3,5-BTC)(H2O)6 architectures with tunable morphologies were successfully prepared on a large scale via a simple and rapid solution phase method at room temperature.
Abstract: Hierarchically nanostructured coordination polymer Ce(1,3,5-BTC)(H2O)6 architectures with tunable morphologies have been successfully prepared on a large scale via a simple and rapid solution phase method at room temperature. The as-synthesized products are characterized by X-ray diffraction, thermogravimetric analysis, energy dispersive X-ray (EDX) analysis, scanning electron microscopy, and transmission electron microscopy, respectively. A possible splitting formation mechanism for the interesting architectures has been proposed to interpret the growth process. By rationally adjusting the synthetic parameters such as concentration, reaction temperature, surfactant, solvent, static, and ultrasonic treatment, Ce(1,3,5-BTC)(H2O)6 with straw-sheaflike, flowerlike, wheatearlike, strawlike, bundlelike, and urchinlike architectures, and nanorods can be selectively obtained. This facile, rapid, mild, cost-effective, reproducible, and environment-friendly growth strategy has considerable potential, and could rea...
156 citations
TL;DR: Two highly porous coordination polymers, containing rare octanuclear hydroxo-nickel clusters and long bis-pyrazolyl spacers, are shown to possess, after mild thermal treatment, lattice cavities up to 72% of the total crystal volume.
Abstract: Two highly porous coordination polymers, containing rare octanuclear hydroxo-nickel clusters and long bis-pyrazolyl spacers, are shown to possess, after mild thermal treatment, lattice cavities up to 72% of the total crystal volume.
139 citations
TL;DR: The experimental results show that the morphologies of polymer nanowires greatly depend on the precursor salts, ratios between deionized water and isopropyl alcohol, and the probable molecular formula and growth mechanism have been proposed.
Abstract: Cobalt ion-based coordination polymer nanowires were synthesized by using nitrilotriacetic acid (NA) as a chelating agent by a one-step hydrothermal approach. In the synthesis, cobalt ions were bonded with amino or carboxyl groups of NA to form one-dimension polymer nanowires, which can be confirmed by FTIR and TGA results. Our experimental results show that the morphologies of polymer nanowires greatly depend on the precursor salts, ratios between deionized water and isopropyl alcohol. The probable molecular formula and growth mechanism have been proposed. After heat treatment, the cobalt ion-based coordination polymer nanowires can be converted into porous Co 3 O 4 nanowires, which completely preserved the nanowire-like morphology. When used as anodes in lithium-ion batteries, the obtained porous Co 3 O 4 nanowires exhibited a high reversible capacity of 810 mA h g -1 and stable cyclic retention at 30th cycle. The good electrochemical performance could be attributed to the porous nanostructure of Co 3 O 4 , which provides pathways for easy accessibility of electrolytes and fast transportation of lithium ions.
TL;DR: The magnetic measurements show a ferromagnetic interaction between Ni(II) and Dy(III), and that both compounds behave like SMM with strong tunnelling.
Abstract: A tetranuclear complex and a 1-D coordination polymer with a ladder-like topology have been obtained by connecting [NiIIDyIII] nodes with dicarboxylato ligands: [Ni2(valpn)2Dy2III(pdca)2(NO3)(H2O)6](NO3)·4H2O 1, and ∞1[Ni2(H2O)2(valpn)2Dy2(tfa)3]·4CH3CN 2 (valpn2− = the dianion of the Schiff base resulting from reacting o-vanillin with 1,3-propanediamine; pdca2− = the dianion of 2,6-pyridinedicarboxylic acid; tfa2− = the dianion of the terephthalic acid). The magnetic measurements show a ferromagnetic interaction between NiII and DyIII, and that both compounds behave like SMM with strong tunnelling. The barrier of 2 (17.4 K) is higher than that of 1 (13.6 K).
TL;DR: Solvothermal reaction of CoSO(4) with 2,6-di-p-carboxyphenyl-4,4'-bipyridine affords a novel, octacobalt cluster based, (3,12)-connected porous framework, which exhibits gas sorption and spin-glassy magnetic behaviour.
TL;DR: The multi-morphological coordination polymer La(1,3,5-BTC)(H2O)6 has been prepared through simple and mild one-step approaches at room temperature on a large scale.
Abstract: The multi-morphological coordination polymer La(1,3,5-BTC)(H2O)6 has been prepared through simple and mild one-step approaches at room temperature on a large scale (1,3,5-BTC = 1,3,5-benzenetricarboxylate). The delicate sheaflike, broccolilike, urchinlike, and fanlike hierarchical architectures made of uniform nanorods were obtained through splitting crystal growth. More interestingly, these three dimensional architectures can exhibit tunable white-light emission by codoping Tb3+ and Eu3+.
TL;DR: A flexible porous coordination polymer with interdigitated structure (CID-3) has been synthesized whose pore size and structural flexibility are suitable for CO(2) capture, providing highly selective adsorption properties of CO( 2) from a ternary O(2), N(2).
TL;DR: A new pillared-layer coordination polymer, [Co(3)(pybz)(2)(pico)(2)](n) (1; pybz = 4-(pyridin-4-yl)benzoate, pico = 3-hydroxypicolinate), contains rare 2D layers formed by linear cobalt(II) trimers through the unusual mu(4)-kappaN,O:kappaO'-mu(2):kappa
Abstract: A new pillared-layer coordination polymer, [Co3(pybz)2(pico)2]n (1; pybz = 4-(pyridin-4-yl)benzoate, pico = 3-hydroxypicolinate), contains rare 2D [Co3(pico)2]n2n+ layers formed by linear cobalt(II) trimers through the unusual μ4-κN,O:κO′-μ2:κO′′-μ2 bridging mode of pico ligands, which are further cross-pillared by exotridentate bridging pybz ligands to form a three-dimensional structure with an unusual uninodal 8-connected body-centered-cubic topology. The bulk magnetic behavior of 1 exhibits ferrimagnetic long-range ordering below 2.6 K, which mainly arises from the cooperative magnetic effect of the intra- and intertrimer arrangements in the 2D magnetic system based on the nature of the exchange modes of μ2-hydroxyl, μ2-carboxylate oxygen, and 1,1,3-μ3-carboxylate bridges.
TL;DR: By connecting [LCuTb](3+) nodes with [Fe(CN)₆]³⁻ spacers a 1-D coordination polymer with slow relaxation of magnetization is obtained.
Abstract: By connecting [LCuTb]3+ nodes with [Fe(CN)6]3− spacers a 1-D coordination polymer with slow relaxation of magnetization is obtained (L2− is the N,N′-propylene-bis(3-methoxysalicylideneiminato) anion).
TL;DR: The exploration of various experimental parameters led to the formation of four crystalline three-dimensional coordination polymers formulated M(2)(TTF-TC)H(2) (M = K, Rb, Cs), denoted MIL-132(K), MIL-133(isostructural K,Rb), and MIL-134(Cs), which all are thermally stable up to 150-200 degrees C in the air.
Abstract: The reactivity of the redox-active tetracarboxylic acid derived from the tetrathiafulvalene (TTF-TC)H4 with alkaline cations (K, Rb, Cs) is reported. The exploration of various experimental parameters (temperature, pH) led to the formation of four crystalline three-dimensional coordination polymers formulated M2(TTF-TC)H2 (M = K, Rb, Cs), denoted MIL-132(K), MIL-133(isostructural K, Rb), and MIL-134(Cs). Thermogravimetric analysis and thermodiffraction show that all of the solids are thermally stable up to 150−200 °C in the air. In order to exploit the possibility of oxidation of the organic linker in TTF-based compounds, they were employed as positive electrodes in a classical lithium cell. A highly reversible cyclability was achieved at high current density (10 C) with a reasonable performance (∼50 mAh g−1). Finally, combined electro-(sub)hydrothermal synthesis was used to prepare a fifth 3-D coordination polymer formulated K(TTF-TC)H2 (denoted MIL-135(K)), this time not based on the neutral TTF-TC link...
TL;DR: Variable temperature magnetic characterizations in the temperature range of 2-300 K indicate that complex 1 is a canted antiferromagnets (weak ferromagnet) with T(c) = 15.9 K, and complex 2 showed unusual ferromagnetic behavior below 40 K because of spin canting.
Abstract: The reaction of pyrimidine-2-carbonitrile, NaN3 in the presence of Co(NO3)2·6H2O or MnCl2·4H2O leads to the formation of complexes [Co(pmtz)(μ1,3-N3)(H2O)]n (1) and [Mn(pmtz)(μ1,3-N3)(H2O)]n (2) respectively, under hydrothermal condition [pmtz =5-(pyrimidyl)tetrazolate]. These two complexes have been fully characterized by single crystal X-ray diffraction. Complex 1 crystallizes in a non-centrosymmetric space group Aba2 in the orthorhombic system and is found to exhibit ferroelectric behavior, whereas complex 2 crystallizes in the P21/c space group in the monoclinic system. Variable temperature magnetic characterizations in the temperature range of 2−300 K indicate that complex 1 is a canted antiferromagnet (weak ferromagnet) with Tc = 15.9 K. Complex 1 represents a unique example of a multiferroic coordination polymer containing tetrazole as a co-ligand. Complex 2 is a one-dimensional chain of Mn(II) bridged by a well-known antiferromagnetic coupler end-to-end azido ligand. In contrast to the role played...
TL;DR: Using reversible polymerization and depolymerization reactions in a single crystal state, the structural frameworks switched between nonporous hexanuclear clusters and porous double-zigzag chains; the magnetic behaviors switched between paramag netism and metamagnetism, respectively.
Abstract: Using reversible polymerization and depolymerization reactions in a single crystal state, we achieved a reversible transformation from a nanocluster to a coordination polymer During the interconversion, the structural frameworks switched between nonporous hexanuclear clusters and porous double-zigzag chains; the magnetic behaviors switched between paramagnetism and metamagnetism, respectively The microporous framework, which had 1D channels 19 A × 36 A in size, exhibited selective gas adsorption of H2 and CO2 over N2
TL;DR: In this paper, a new zinc(II) nitrite coordination polymer, ZnN2O4, was prepared and characterized by elemental analyses and IR spectroscopy, and the thermal stability of nano-structure ZnO was studied by thermal gravimetric and differential thermal analyses and showed that there is no reportable loss of weight in the TGA curves that proves the existence of zinc oxide.
TL;DR: In the case of exchange by Cl(-) ion, the crystallinity is not maintained, and so it is proven by IR spectroscopy, PXRD, and elemental analysis.
Abstract: A new non-interpenetrated two-dimensional (2D) rectangular-grid coordination polymer, {[Co(L)2(H2O)2]·(BF4)2·4DMF}n (1), has been synthesized using a new rod-like ligand, 3,5-bis(4-imidazol-1-ylphenyl)-[1,2,4]triazol-4-ylamine (L). Weakly H-bonded BF4− anions present within the voids can be exchanged by ClO4− and NO3− anions to generate {[Co(L)2(H2O)2]·(ClO4)2·2DMF·2H2O}n (2) and {[Co(L)2(H2O)2]·(NO3)2·2DMF·2H2O}n (3) in single-crystal-to-single-crystal (SC-SC) manner. In the case of exchange by Cl− ion, the crystallinity is not maintained, and so it is proven by IR spectroscopy, PXRD, and elemental analysis. In addition, 3 shows an interesting structural transformation (2D → 1D) with bond rupture/formation leading to the formation of a new coordination polymer, {[Co(L)2(H2O)2]·(NO3)2·2DMF·H2O}n, (5), again in SC-SC fashion.
TL;DR: In this article, an asymmetric semi-rigid V-shaped multicarboxylate ligand with the help of 4,4-bipyridine (4,4′-bpy) ligand was used to construct the first metal-organic hybrid tube.
Abstract: Novel nickel(II) coordination polymers have been constructed from asymmetric semi-rigid V-shaped multicarboxylate ligands with the help of 4,4′-bipyridine (4,4′-bpy) ligand. The hydrothermal reaction between 3-(4-carboxy-phenoxy)-phthalic acid (H3L1) and Ni(OAc)2·4H2O led to the formation of [Ni3(L1)2(μ-4,4′-bpy)3(H2O)2]n·(4,4′-bpy)n·(H2O)5n (1). In contrast, the same reaction using 3-(2-carboxy-phenoxy)-phthalic acid (H3L2) as a starting material instead of H3L1 resulted in [Ni3(L2)2(H2O)4(μ-4,4′-bpy)3]n·(H2O)2n (2) and [Ni3(L2)2(H2O)4(μ-4,4′-bpy)4]n·(H2O)2n (3) at 120 and 150 °C, respectively, revealing the effect of reaction temperature on the structure of the coordination polymer formed from the semi-rigid V-shaped ligand of L2. Single-crystal X-ray diffraction analysis reveals that complex 1 shows a 3D framework structure assembled from right- and left-handed helices together with isolated tubes. This compound represents the first metal–organic hybrid tube constructed from an asymmetric semi-rigid V-shaped multicarboxylate ligand. Compound 2 also exhibits a 3D network composed of discontiguous trinuclear Ni(II) clusters, while the 3D architecture of 3 consisting of isolated Ni(II) ions separated in a long distance is constructed by two kinds of 2D (6,3) networks. Magnetic studies reveal the overall antiferromagnetic interaction between the neighbouring Ni(II) ions in 1–3.
TL;DR: Compared with its homogeneous counterparts, the immobilised gel catalyst exhibited significantly improved catalytic activity under mild conditions as shown in Suzuki–Miyaura C–C coupling, and could be reused for several times.
Abstract: A metal–organic gel (MOG) route to immobilised catalysts has been developed based on the reversibility of coordination bond formation in a Fe3+–carboxylate MOG. The ferric gel was rationally designed based on a bifunctional ligand, 5-1H-benzo[d]imidazole-1,3-dicarboxylic acid (L1), in which the imidazole N atom may further bind to a soft ion like Pd2+ more strongly due to the HSAB matching. Palladium(II) was successfully loaded in the gel to yield a supported coordination catalyst. Compared with its homogeneous counterparts, the immobilised gel catalyst exhibited significantly improved catalytic activity under mild conditions as shown in Suzuki–Miyaura C–C coupling, and could be reused for several times.
TL;DR: In this paper, an investigation into 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (bpt) and cupric or cadmium complexes with a large variety of aliphatic α,ω-dicarboxylic acids HOOC-X-COOH (X = (CH2)n, n = 0-4 corresponding to oxalic acid (H2ox), malonic acid (h2mal), succinic acid(H2suc), glutaric
Abstract: An investigation into 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (bpt) and cupric or cadmium complexes with a large variety of aliphatic α,ω-dicarboxylic acids HOOC-X-COOH (X = (CH2)n, n = 0–4 corresponding to oxalic acid (H2ox), malonic acid (H2mal), succinic acid (H2suc), glutaric acid (H2glu) and adipic acid (H2adi); CHCH, maleic acid (H2male) and fumaric acid (H2fum)) is performed. Ten novel metal–organic architectures, [Cu2(bpt)(ox)2]n·2.92nH2O (1), [Cu(bpt)(mal)(H2O)]n·2nH2O (2), [Cu(bpt)(glu)]n (3), [Cu(bpt)(adi)]n (4), [Cu2(bpt)2(fum)2]n·3nH2O (5), [Cd(bpt)(mal)(H2O)]n (6), [Cd(bpt)(suc)]n (7), [Cd(bpt)(glu)]n·nH2O (8), [Cd2(bpt)2(male)2]n·2nH2O (9), and [Cd(bpt)(fum)(H2O)]n·nH2O (10) were successfully synthesized through varying the organic acid linkers. The molecule 1 is a 3D pillared-layer framework with the open channels encapsulating infinite 1D water chains. Complex 2 shows the contorted 2D layer, which is extended to a 2-fold interpenetrated 3D supramolecular net by antidromic R24(8) hydrogen-bonding pattern. Compound 3 is a grid-like layer motif with the terminal bpt ligands as pendants. The MOFs 4 and 5 present two-fold interpenetrating primitive cubic (α-Po) coordination networks. Interestingly, discrete tetrameric water clusters exist in the micropores of the MOF 5. For the cadmium complex 6, six-coordinated metal centers link malonate and bpt to form interdigitated layers through edge-to-face π–π stacking interactions. Coordination polymer 7 can be considered as six-connected self-penetrated topological 3D network, in which the right- and left-handed helices are alternately arranged into a wavy Cd/succinate layer. Flexible glutarate with cadmium atoms produces a 1D ribbon, and is further linked by bpt ligands to produce the 2D double-layered motif 8. Incorporating with rigid butenedioic acid, the reaction of seven-coordinated cadmium and bpt leads to two distinct 2D (4,4) layered frameworks 9 and 10, with a one-dimensional Cd–O chain observed in the former framework. A systematic structural comparison of these ten complexes indicates that the final polymeric structures could be tuned through the introduction of the different backbone length and flexibility of the aliphatic dicarboxylates. In addition, host–guest chemistry of MOFs 1 and 5, and the luminescent properties of cadmium compounds were discussed.
TL;DR: A new spin crossover (SCO) coordination polymer, {[Fe(II)(4-methylpyridine)(2)][Au(I)(CN)(2)](2)}(n) () has been synthesized and has been observed to have a thermal induced three-step SCO transition, which is unprecedented behavior as compared with existing SCO complexes.
Abstract: A new spin crossover (SCO) coordination polymer, {[FeII(4-methylpyridine)2][AuI(CN)2]2}n (1) has been synthesized. The complex (1) has been observed to have a thermal induced three-step SCO transition, which is unprecedented behavior as compared with existing SCO complexes. In the complex, about 18%, 41% and 41% high spin states are changed to low spin states in the first-step, second-step and third-step, respectively.
TL;DR: A novel mixed-valent Ag(I)/Ag(II) coordination polymer was synthesized and characterized and the results show it presents semiconducting and photoluminescent properties.
TL;DR: The ability of a carboxylic acid functionalized spiropyran, SP, to act as a reversible and selective receptor for metal ions has been systematically examined.
Abstract: The ability of a carboxylic acid functionalized spiropyran, SP, to act as a reversible and selective receptor for metal ions has been systematically examined. A series of spectroscopic measurements, combined with single-crystal X-ray diffraction have been employed in order to determine metal-ion sensitivity and selectivity, binding constants, solution compositions, binding kinetics as well as solid-state structure of a metal-complex of this ligand. This molecule acts as a chelating ligand and binds to metal ions using a triad of functionalities and will release the metal ion by application of visible light. Altering the complex from ZnCl(2) and Zn(ClO(4))(2), leads to only a small change in the complex absorption maxima from 494 to 492 nm, but produced a drastic increase in the sensitivity for the zinc(II) ion. Fluorescence spectroscopy was employed to establish that the detection limit for Zn(II) is approximately 3 x 10(-7) M for Zn(ClO(4))(2). The counterion also influences binding constants and the equilibrium constants for Cu(ClO(4))(2) and CuCl(2) are K = 3.37 x 10(4) M(-1) to K = 2.04 x 10(3) M(-1), respectively. Additionally, in the presence of perchlorate, the spiropyran-Cu complex formation is fast enough to allow for real-time naked eye detection of this metal ion in less than three minutes; the formation of other metal complexes takes between 50 minutes to 2 hours. Finally, the single-crystal structure determination of the SP-zinc chloride complex shows that the Zn(II) ion displays a distorted square-pyramidal arrangement, and neighbouring metal ions are bound together into a 1-D coordination polymer with a hydrophilic core, surrounded by hydrophobic 'cladding'.
TL;DR: Results of results of MeOH, EtOH, IPA, and Me(2)CO adsorption/desorption on 2-4 shows an obvious two-step profile, which depends on the temperature and the small free-energy difference between the two guest-free forms, wide and narrow pores.
Abstract: A preliminary study of isopropanol (IPA) adsorption/desorption isotherms on a jungle-gym-type porous coordination polymer, [Zn2(bdc)2(dabco)]n (1, H2bdc = 1,4-benzenedicarboxylic acid, dabco =1,4-diazabicyclo[2.2.2]octane), showed unambiguous two-step profiles via a highly shrunk intermediate framework. The results of adsorption measurements on 1, using probing gas molecules of alcohol (MeOH and EtOH) for the size effect and Me2CO for the influence of hydrogen bonding, show that alcohol adsorption isotherms are gradual two-step profiles, whereas the Me2CO isotherm is a typical type-I isotherm, indicating that a two-step adsorption/desorption is involved with hydrogen bonds. To further clarify these characteristic adsorption/desorption behaviors, selecting nitroterephthalate (bdc-NO2), bromoterephthalate (bdc-Br), and 2,5-dichloroterephthalate (bdc-Cl2) as substituted dicarboxylate ligands, isomorphous jungle-gym-type porous coordination polymers, {[Zn2(bdc-NO2)2(dabco)]·solvents}n (2 ⊃ solvents), {[Zn2(bd...