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Cu fragments in γ-cyclodextrins show different properties from those of unincluded fragments caused by the confinement and the interaction between Cu fragments.

The ligand field (LF) of transition metal ions is a crucial factor in realizing the mechanism of novel physical and chemical properties. However, the low-crystallinity state, including the amorphous state, precludes the clarification of the electronic structural relationship of transition metal ions using crystallographic techniques, ultraviolet and infrared optical methods, and magnetometry. Here, we demonstrate that soft X-ray 2p → 3d core-level absorption spectroscopy (

The zero area TE of cyanide-bridged honeycomb layers occurs by complementary structural changes in the cation and anion counterparts.

Layer flexibility in two-dimensional coordination polymers (2D-CPs) contributes to several functional materials as it results in anisotropic structural response to external stimuli. Chemical modification is a common technique for modifying layer structures. This study demonstrates that crystal morphology of a cyanide-bridged 2D-CP of type [Mn(salen)]2 [ReN(CN)4 ] (1) consisting of flexible undulating layers significantly impacts the layer configuration and assembly. Nanoplates of 1 showed an in-plane contraction of layers with a longer interlayer distance compared to the micrometer-sized rod-type particles. These effects by crystal morphology on the structure of the 2D-CP impacted the structural flexibility, resulting in dual-functional changes: the enhancement of the sensitivity of structural transformation to water adsorption and modification of anisotropic thermal expansion of 1. Moreover, the nanoplates incorporated new adsorption sites within the layers, resulting in the uptake of an additional water molecule compared to the micrometer-sized rods.

The negative thermal expansion (NTE) of solid-state materials is of significance in various fields, but a very rare phenomenon. In this study, we carried out a meta-analysis for the anisotropic thermal expansion behavior of fifteen two-dimensional coordination polymers [M(salen)]

A luminescent two-dimensional coordination polymer of type [Cd(H2O)(EtOH)][ReN(CN)4(H2O)]·2H2O (CdRe) incorporating “Janus-type” cyanido-bridged layers was synthesized. Within each layer of CdRe, t...

Chemical responsivity in materials is essential to build systems with switchable functionalities. However, polarity-switchable materials are still rare because inducing a symmetry breaking of the crystal structure by adsorbing chemical species is difficult. In this study, we demonstrate that a molecular organic-inorganic hybrid crystal of (NEt

Metal-organic polyhedra (MOPs) can act as elementary structural units for the design of modular porous materials; however, their association with biological systems remains greatly restricted by their typically low stabilities and solubilities in water. Hereby, we describe the preparation of novel MOPs bearing either anionic or cationic groups and exhibiting a high affinity for proteins. Simple mixing of protein (BSA) and ionic MOPs aqueous solutions resulted in the spontaneous formation of MOP-protein assemblies, in a colloidal state or as solid precipitates depending on the initial mixing ratio. The versatility of the method was further illustrated using two enzymes, catalase and cytochrome c, with different sizes and isoelectric points (pI) below and above 7. This mode of assembly led to the high retention of catalytic activity and enabled recyclability. Furthermore, the co-immobilization of cytochrome c with highly charged MOPs resulted in a substantial 44-fold increase of its catalytic activity.

Mastering nanostructuration of functional materials into electronic devices is presently an essential task in materials science. This is particularly relevant for spin crossover (SCO) compounds, whose properties are extremely sensitive to size reduction. Indeed, the search for materials displaying strong cooperative hysteretic SCO properties operative at the nanoscale close near room temperature is extremely challenging. In this context, we describe here the synthesis and characterization of 20-30 nm surfactant-free nanocrystals of the FeII Hofmann-type polymer {FeII(pz)[PtII,IVIx(CN)4]} (pz = pyrazine), which affords the first example of a robust three-dimensional coordination polymer, substantially keeping operational thermally induced SCO bistability at such a scale.

We demonstrate a fluid-fluid phase separation in 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) membranes using a metal complex lipid of type [Mn(L1)] (1; HL1 = 1-(2-hydroxybenzamide)-2-(2-hydroxy-3-formyl-5-hexadecyloxybenzylideneamino)ethane. Small amount of 1 produces two separated domains in DMPC, whose phase transition temperatures of lipids (Tc) are both lower than that of the pristine DMPC. Variable temperature fluorescent microscopy for giant-unilamellar vesicles of DMPC/1 hybrids demonstrates that visible phase separations remain in fluid phases up to 37 °C, which is clearly over the Tc of DMPC. This provides a new dimension for the application of metal complex lipids toward controlling lipid distributions in fluid membranes.

Controlling gas sorption by simple pore modification is important in molecular recognition and industrial separation processes. In particular, it is challenging to realize the inverse selectivity, which reduces the adsorption of a high-affinity gas and increases the adsorption of a low-affinity gas. Herein, an "opposite action" strategy is demonstrated for boosting CO2 /C2 H2 selectivity in porous coordination polymers (PCPs). A precise steric design of channel pores using an amino group as an additional interacting site enabled the synergetic increase in CO2 adsorption while suppressing the C2 H2 adsorption. Based on this strategy, two new ultramicroporous PCP physisorbents that are isostructural were synthesised. They exhibited the highest CO2 uptake and CO2 /C2 H2 volume uptake ratio at 298 K. Origin of this specific selectivity was verified by detailed density functional theory calculations. The breakthrough separation performances with remarkable stability and recyclability of both the PCPs render them relevant materials for C2 H2 purification from CO2 /C2 H2 mixtures.

The excited-state energy was tuned successfully by guest molecules in a cyanide-bridged luminescent coordination polymer (CP). Methanol or ethanol vapor reversibly and significantly changed the luminescent color of the CP between green and yellow (Δλem = 32 nm). These vapors did not significantly affect the environment around the luminophore in the ground state of the CP, whereas they modulated the excited states for the resulting bathochromic shift. The time-resolved photoluminescent spectra of the CP systems showed that solvent adsorption enhanced the energetic relaxation in the excited states. Furthermore, time-resolved infrared spectroscopy indicated that cyanide bridging in the CP became more flexible in the excited states than that in the ground state, highlighting the sensitivity of the excited states to external stimuli, such as the guest vapor. Overall, guest-tunable excited states will allow the more straightforward design of sensing materials by characterizing the transient excited states.

Amorphous coordination polymers and metal-organic frameworks (MOFs) have attracted much attention owing to their various functionalities. Here, we demonstrate the tunable water adsorption behavior of a series of amorphous cyanide-bridged MOFs with different metals (M[Ni(CN)4]: MNi; M = Mn, Fe, and Co). All three compounds adsorb up to six water molecules at a certain vapor pressure (Pads) and undergo conversion to crystalline Hofmann-type MOFs, M(H2O)2[Ni(CN)4]·4H2O (MNi-H2O; M = Mn, Fe, and Co). The Pads of MnNi, FeNi, and CoNi for water adsorption is P/P0 = 0.4, 0.6, and 0.9, respectively. Although the amorphous nature of these materials prevented structural elucidation using X-ray crystallography techniques, the local-scale structure around the N-coordinated M2+ centers was analyzed using L2,3-, K-edge X-ray absorption fine structure, and magnetic measurements. Upon hydration, the coordination geometry of these metal centers changed from tetrahedral to octahedral, resulting in significant reorganization of the MOF local structure. On the other hand, Ni[Ni(CN)4] (NiNi) containing square-planar Ni2+ centers did not undergo significant structural transformation and therefore abruptly adsorbed H2O in the low-pressure region. We could thus define how changes in the bond lengths and coordination geometry are related to the adsorption properties of amorphous MOF systems.

Amphotericin B incorporating 2,2'-bipyridine (bpy-AmB) forms a membrane channel exhibiting pH-dependent Ca2+ ion permeability with a selective response to Cu2+ ions. The coordination structure at bpy sites depends on the pH and metal ions can control the association state of bpy-AmB in the membrane.

A novel porous magnet consisting of cationic two-dimensional (2-D) layers extended by FeIII–CN–NiII linkages and pseudo-pillar dianions was synthesized. The size-selective guest adsorption behaviour of water and methanol molecules originates from the narrow bottle-neck-type pores in the flexible pseudo-pillared-layer structure, which results in the switching of the magnetic phases from antiferromagnetic to ferromagnetic, involving significant changes in the interlayer distance.

Metal node design is crucial for obtaining structurally diverse coordination polymers (CPs) and metal?organic frameworks with desirable properties; however, FeII ions are exclusively six-coordinated. Herein, we present a cyanide-bridged three-dimensional (3D) CP, FePd(CN)4, bearing four-coordinate FeII ions, which is synthesized by thermal treatment of a two-dimensional (2D) six-coordinate FeII CP, Fe(H2O)2Pd(CN)4?4?H2O, to remove water molecules. Atomic-resolution transmission electron microscopy and powder X-ray and neutron diffraction measurements revealed that the FePd(CN)4 structure is composed of a two-fold interpenetrated PtS topology network, where the FeII center demonstrates an intermediate geometry between tetrahedral and square-planar coordination. This four-coordinate FeII center with the distorted geometry can act as a thermo-responsive flexible node in the PtS network.

A sixfold interpenetrated metal–organic framework (MOF) with dia topology isolated in the first attempt could not be reproduced; subsequent synthesis yielded only the double-pillared-layer MOF. However, this ‘disappeared supramolecular isomer’ reappears in the presence of a perylene guest., Among different types of polymorphism, disappearing polymorphism deals with the metastable kinetic form which can not be reproduced after its first isolation. In the world of coordination polymers (CPs) and metal–organic frameworks (MOFs), despite the fact that many types of supramolecular isomerism exist, we are unaware of disappearing supramolecular isomerism akin to disappearing polymorphism. This work reports a MOF with dia topology that could not be reproduced, but subsequent synthesis yielded another supramolecular isomer, a double-pillared-layer MOF. When perylene was added in the same reaction, the disappeared dia MOF reappeared with perylene as a guest in the channels. Interestingly, the photoluminescence of the dia MOF with a perylene guest is dominated by the emission of the guest molecule. The influence of guest molecules on the stabilization of the supramolecular isomers of a MOF opens up a strategy to access MOFs with different structures.

The ortho-isomer of molecular hydrogen (o-H2) was converted to the para-isomer (p-H2) within 600 s by using Prussian blue analogs, {MII3[CrIII(CN)6]2} (MCr; M = Mn and Ni), as nuclear-spin conversi...

A ReV complex demonstrates methanol selective luminescent color changes from red to green together with enhancements of the corresponding luminescence quantum yields twenty-three times. These characteristic responses are caused by the switching of the characters of the emissive states from metal-to-ligand charge transfer to d-d transition along with a single-crystal-to-single-crystal ligand exchange reaction.

Mastering nanostructuration of functional materials into electronic devices is presently an essential task in materials science. This is particularly relevant for spin crossover (SCO) compounds, whose properties are extremely sensitive to size reduction. Indeed, the search for materials displaying strong cooperative hysteretic SCO properties operative at the nanoscale close near room temperature is extremely challenging. In this context, we describe here the synthesis and characterization of 20-30 nm surfactant-free nanocrystals of the Fe

Two-dimensional Hofmann-type coordination polymers of type Mn(H2O)2[Pd(CN)4]·xH2O (1·xH2O; x = 0, 1, and 4), Mn(H2O)(MeOH)[Pd(CN)4]·2MeOH (2·2MeOH), and Mn(MeOH)2[Pd(CN)4]·MeOH (3·MeOH) have been synthesized. The homosolvent-bound 1·4H2O, 1·H2O, and 3·MeOH polymers consist of undulating layer structures, whereas the structure of heterosolvent-bound 2·2MeOH consists of "Janus-like" flat layers in which water-bound and MeOH-bound-sides are present. 1·4H2O and 1·H2O exhibited anisotropic two-dimensional thermal expansions involving structural transformations of the undulating layers; one layer axis expands while the other contracts. 2·2MeOH exhibits anisotropic thermal expansion in which the flat layers shift sideways as the temperature is increased, with colossal interlayer expansion occurring (αc = +200 MK-1 over 140-180 K, αc = +165 MK-1 over 200-280 K). 3·MeOH also showed colossal interlayer expansion (αc = +216 MK-1) together with expansion of the undulating layers.

In the doubly interpenetrated metal–organic framework (MOF) structure with cds topology, [Zn2(bpeb)(dhbdc)(fa)2], 1 (where bpeb = trans,trans,trans-1,4-bis[2-(4′-pyridyl)ethenyl]benzene, dhbdc = 2,...

A supply chain is a system consisting of different entities, which add value from the original resources to the final products for customers. Although each entity is indispensable for the construction of a supply chain, the degree of importance of each entity varies depending on the role played in the supply chain. In this paper, we assume that the information produced by the entity that plays a more important role should be referred to more by other entities when making appropriate decisions to effectively operate the entire supply chain. Thus, we developed a method that evaluates the soundness of the supply chain based on the structure of its information network. In the method, the structure of the supply chain information network is expressed in a square matrix A. The eigenvector R of the matrix A is assumed as the rate of its own information referred to by other entities in the supply chain. The value of information produced by each entity is represented as a vector V determined by using AHP. Then, the method evaluates the soundness of the supply chain as the norm between R and V. In addition, a design method to search for the ideal structure of the information network is presented. The effectiveness of the proposed method is examined by using simple supply chain models.

Charge-driven self-assembly of cationic zirconium-based metal–organic polyhedra (MOPs) with polyoxometalates (POMs) leads to a series of porous crystalline salts, prepared by simple mixing of soluble precursors. The reactivity of immobilized POMs was greatly increased, as demonstrated by their fast reduction by hydrazine vapors, without loss of structural integrity.

Controlling gas sorption by simple pore modification is important in molecular recognition and industrial separation processes. In particular, it is challenging to realize the inverse selectivity, which reduces the adsorption of a high-affinity gas and increases the adsorption of a low-affinity gas. Herein, an "opposite action" strategy is demonstrated for boosting CO

Recently, non-crystalline coordination materials have been shown to represent a versatile class of functional materials. However, such materials incorporating metal complex clusters have remained largely unexplored. Herein, we demonstrate that a luminescent tetranuclear ReV cluster melts at 489 K, with the cluster structure being maintained in the corresponding supercooled ionic liquid phase.

Metal node design is crucial for obtaining structurally diverse coordination polymers (CPs) and metal-organic frameworks with desirable properties; however, Fe

Cell membranes contain lateral systems that consist of various lipid compositions and actin cytoskeleton, providing two-dimensional (2D) platforms for chemical reactions. However, such complex 2D environments have not yet been used as a synthetic platform for artificial 2D nanomaterials. Herein, we demonstrate the direct synthesis of 2D coordination polymers (CPs) at the liquid-cell interface of the plasma membrane of living cells. The coordination-driven self-assembly of networking metal complex lipids produces cyanide-bridged CP layers with metal ions, enabling "pseudo-membrane jackets" that produce long-lived micro-domains with a size of 1-5 μm. The resultant artificial and visible phase separation systems remain stable even in the absence of actin skeletons in cells. Moreover, we show the cell application of the jackets by demonstrating the enhancement of cellular calcium response to ATP.

Inorganic chemical cells (iCHELLs) are compartment structures consisting of polyoxometalates (POMs) and cations, offering structured and confined reaction spaces bounded by membranes. We have constructed a system capable of efficient anisotropic and hierarchical photo‐induced electron transfer across the iCHELL membrane. Mimicking photosynthesis, our system uses proton gradients between the compartment and the bulk to drive efficient conversion of light into chemical energy, producing hydrogen upon irradiation. This illustrates the power of the iCHELL approach for catalysis, where the structure, compartmentalisation and variation in possible components could be utilised to approach a wide range of reactions.

The palladium-hydrogen system is one of the most famous hydrogen-storage systems. Although there has been much research on β-phase PdH(D)x , we comprehensively investigated the nature of the interaction between Pd and H(D) in α-phase PdH(D)x (x

Coordination polymer (CP) nanoparticles (NPs) formed by a self-assembly of organic ligands and metal ions are one of the attractive materials for molecular capture and deliver/release in aqueous media. Control of particle size and prevention of aggregation among CP NPs are important factors for improving their adsorption capability in water. We demonstrate here the potential of a liposome incorporating an antibiotic ion channel as a vessel for synthesizing Prussian blue (PB) NPs, being a typical CP. In the formation of PB NPs within liposomes, the influx rate of Fe2+ ions into liposome encapsulated [Fe(CN)6]3– through channels was fundamental for the change of NPs’ sizes. The optimized PB NP–liposome composite showed higher adsorption capacity of Cs+ ions than that of aggregated PB NPs that are prepared without liposome in aqueous media.

Three types of cubane-based complexes, [Co4(L1-H)4Cl2(MeOH)2] (1) [H2L1-H = N-(2-hydroxymethylphenyl)salicylideneimine], [Ni4(L1-Bz)4(EtOH)4] (2) [H2L1-Bz = N-(2-hydroxymethylphenyl)-5,6-benzosalicylideneimine], and [Co2Ni(L1-H)2(HL1-H)(CH3COO)2] (3), have been characterized by X-ray crystal structure analyses and magnetic measurements. Homo-metal complexes 1 and 2 are tetranuclear complexes. Complex 1 has a defective double-cubane metal core. The valence state of cobalt ions is assigned to mixed valence Co(II)2Co(III)2. On the contrary, 2 takes a simple cubane core comprised of four [Ni(II)(L1-Bz)] monomer units. Complex 3 has a novel hetero-metal and mixed-valence trinuclear metal core structure. Cryomagnetic studies for 1–3 indicate that ferromagnetic interactions are dominate due to the cubane-based metal core structures.

We report size-controllable syntheses of spherical coordination polymer particles using only K2[Pt(CN)4], Zn(NO3)2·6H2O, and water, and their conversion to Pt-ZnO composite and PtZn alloy. This method can control both the size and surface morphology of coordination polymer particles by changing the concentrations of the starting materials without any organic solvents, surfactants, and heating treatment. For example, the increasing of [Pt(CN)4]2− concentration reduced the particle size and improved the smoothness of particle surface. Thermal treatment of the particles in oxidative atmosphere at 500 °C results in the formation of Pt-ZnO composite. Upon further treatment in reducing atmosphere at 400 °C, the composite was converted to PtZn alloy compound. After conversion to composite and alloy, the initial particle size and surface morphology were retained.

Selective partitioning of fluorescein and zinc protoporphyrin into a liquid disordered (Ld) lipid domain was achieved in liposomes, providing an appropriate platform for fluorescence resonance energy transfer (FRET). The efficiency of FRET in the resulting liposome composites was regulated by simply adjusting the domain size. As the domain size was reduced, the density of fluorophores and zinc protoporphyrin in the Ld domain increased, resulting in the improvement of FRET efficiency.

Controlled nucleation in a micromixer and further crystal growth were used to synthesize Ni2(2,6-ndc)2dabco (2,6-ndc – 2,6-naphthalenedicarboxylate, dabco – 1,4-diazabicyclo[2.2.2]octane), also termed DUT-8(Ni) (DUT = Dresden University of Technology), with narrow particle size distribution in a range of a few nm to several μm. The crystal size was found to significantly affect the switching characteristics, in particular the gate opening pressure in nitrogen adsorption isotherms at 77 K for this highly porous and flexible network. Below a critical size of about 500 nm, a type Ia isotherm typical of rigid MOFs is observed, while above approximately 1000 nm a pronounced gating behaviour is detected, starting at p/p0 = 0.2. With increasing crystal size this transition gate becomes steeper indicating a more uniform distribution of activation energies within the crystal ensemble. At an intermediate size (500–1000 nm), the DUT-8(Ni) crystals close during activation but cannot be reopened by nitrogen at 77 K possibly indicating monodomain switching.

Mesocrystals of a porous coordination polymer {Fe(pz)[Pt(CN)4]} (1) showing spin transition were prepared by the reverse micelle method, and the size-controlled mesocrystal 1 kept its porous property and magnetic bistability and exhibited higher guest-responsivity with switching the spin state in both solid and aqueous suspension states than the bulk 1.

The linear multidentate-type ligand 2,6-di(acetoacetyl)pyridine (H2L) selectively gave di- and octa-nuclear complexes, [M2(HL)2(NO3)2(H2O)2] (M2(HL)2) and [M8(L)6(μ3-O)2] (M8L6), with metal ions (MII = Mn, Co, Zn) by adjusting pH. M2(HL)2 formed an enolate-bridged dinuclear structure, in which metal ions were in hepta-coordinated pentagonal-bipyramid geometry. The structure of M8L6 consisted of two tetranuclear components including mononuclear [MnL3]4− and trinuclear [Mn(μ3-O)]4+ units, and the tetrads were interdigitated by enolate-bridges. In methanolic solution, M2(HL)2 was irreversibly transformed to M8L6 with liberation extra L2− by the addition of base.