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An alternative approach for achieving negative thermal expansion (NTE) in a molecular crystal of [Ni(dmit)2]− salt with supramolecular cation composed of pyridazinium and dibenzo[24]crown-8. Deformation of supramolecular cation induces NTE and peculiar magnetic responses.

BACKGROUND: The clinical spectrum of idiopathic normal pressure hydrocephalus (iNPH) comprises the triad of gait disturbance, cognitive impairment, and urinary incontinence. However, motor abnormalities involving the upper extremities in iNPH patients have few quantitative studies. OBJECTIVE: The present study was designed to quantitatively assess bimanual tapping tasks in iNPH patients and to compare with the control groups. METHODS: The subjects were divided into three groups: iNPH patients, older healthy group, and younger healthy group. The tasks were three synchronization finger-to-thumb tapping tasks with the auditory stimuli specified at 1 Hz by metronome: unilateral, bimanual simultaneous, and bimanual alternate. Two-way ANOVA was used to compare the outcomes of the three errors (absolute error: AE, variable error: VE, and constant error: CE) for tapping cycles. RESULTS: In the iNPH group, the absolute and variable errors increased in bimanual alternate tapping task with statistical significance (AE: p

Using Na-encapsulated benzo[18]crown-6 (Na)(B18C6) as a counter cation, we successfully magnetically isolated a fluoride-bridging Dy dinuclear complex {[(PW11O39)Dy(H2O)(2)](2)F} (Dy2POM) with lacunary Keggin ligands. (Na)(B18C6) formed two types of tetramers through C-HMIDLINE HORIZONTAL ELLIPSISO, pi MIDLINE HORIZONTAL ELLIPSIS pi and C-HMIDLINE HORIZONTAL ELLIPSIS pi interactions, and each tetramer aligned in one dimension along the c-axis to form two types of channels. One channel was partially penetrated by a supramolecular cation from the +/- a-axis direction, dividing the channel in the form of a bamboo node. Dy2POM was spatially divided by this bamboo node, which magnetically isolated one portion from the other. The temperature dependence of the magnetic susceptibility indicated a weak ferromagnetic interaction between the Dy ions bridged by fluoride. Dy2POM exhibited the magnetic relaxation characteristics of a single-molecule magnet, including the dependence of AC magnetic susceptibility on temperature and frequency. Magnetic relaxation can be described by the combination of thermally active Orbach and temperature-independent quantum tunneling processes. The application of a static magnetic field effectively suppressed the relaxation due to quantum tunneling.

Mechanical force can be employed not only to efficiently synthesize new materials under environmentally friendly conditions but also to change the macroscopic and microscopic properties of materials. Although coordination polymers (CPs) are attractive functional materials because they possess high structural designability and diversity, mechanical force-induced structural and functional changes of CPs are challenging issues. In this study, two one-dimensional CPs, one a densely packed nonporous CP [Cu

The orientation of (4-carboxybutan-1-aminium)([18]crown-6), as well as the rotational behaviour of [18]crown-6, is triggered by guest CH3OH through hydrogen bond reorganisation.

Slider-crank like force conversion of linear thermal expansion to rotational motion of the coordination chains were observed in the molecular crystal.

We demonstrate that a dipole-dipole interaction of benzo[c][1,2,5]thiadiazole moieties, directional H-bond formation of carboxy groups, and a rigid molecular skeleton enable a structurally-predicta...

A rigid hydrogen-bonded organic framework (HOF) was constructed from a C

Semiconductors that emit intrinsic white light are considered next-generation lighting sources. Herein, the broadband emission of one-dimensional (1D) lead halide perovskites, TMAPbBr

Breast cancer susceptibility gene 1 (BRCA1)-associated ovarian cancer patients have been treated with A poly (ADP-ribose) polymerase (PARP) inhibitor, extending the progression-free survival; however, they finally acquire therapeutic resistance. Interleukin (IL)-34 has been reported as a poor prognostic factor in several cancers, including ovarian cancer, and it contributes to the therapeutic resistance of chemotherapies. IL-34 may affect the therapeutic effect of PARP inhibitor through the regulation of tumor microenvironment (TME).In this study, The Cancer Genome Atlas (TCGA) data set was used to evaluate the prognosis of IL-34 and human ovarian serous carcinoma. We also used CRISPR-Cas9 genome editing technology in a mouse model to evaluate the efficacy of PARP inhibitor therapy in the presence or absence of IL-34.We found thatThese results suggest that tumor-derived IL-34 benefits tumors by creating an immunosuppressive TME and conferring PARP inhibitor therapeutic resistance. Thus, we showed the pathological effect of IL-34 and the need for it as a therapeutic target in ovarian cancer.

Porous organic frameworks possessing interactive free sites in the pore have attracted much attention due to their potential to show the site-originated specific functionalities. Herein, we demonstrate that such a framework could be constructed using a concept of geometrically mismatched frameworks composed of phenanthroline-based tetratopic carboxylic acid CP-Phen. Simple recrystallization of CP-Phen yielded a solvent included porous framework CP-Phen-1, in which three of four carboxy groups form hydrogen-bonded dimer to form a ladder-shaped framework, while the remained one does not participate in framework formation due to geometrical mismatch and interacts with solvent molecules through weak hydrogen-bonding. This result implies that our proposed strategy is effective to provide free interactive sites in porous frameworks. Although CP-Phen-1 undergoes two-step structural transformation presumably accompanied by hydrogen-bond rearrangements upon loss of solvent molecules, the activate framework shows good thermal stability up to 360 °C and selective CO

Molecular motion within crystals can significantly affect their dielectric properties and functionalities. Crystals of (m-XAni+)(DB[18]crown-6)[Ni(dmit)2]− (m-XAni+ = m-halogenated anilinium (X = F...

A series of mononuclear CuII complexes, [CuII(4-FBA)2(py)2(H2O)] (1), [CuII(3-FBA)2(py)2(H2O)] (2), and [CuII(3,4-F2BA)2(py)2(H2O)] (3), where 4-FBA = 4-fluorobenzoate, 3-FBA = 3-fluorobenzoate, 3,4-F2BA = 3,4-difluorobenzoate, and py = pyridine, respectively, was synthesized and the complexes crystallographically identified. All the CuII complex crystals share a one-dimensional O–H⋯O hydrogen-bonding chain substructure, although the mutual alignment of fluorinated benzoate (FxBA) ligands exhibits subtle differences among the various compounds, i.e., FxBA ligands align in an antiparallel fashion in crystals 1 and 3, while 3-FBA ligands in crystal 2 are interdigitated with a tilt along the a axis. Reversible phase transitions were found upon heating at 170.7, 171.3, and 267.5 K for crystals 1, 2, and 3, respectively; all crystals showed approximately 3% expansion and shrinkage of the intermolecular O–H⋯O hydrogen bond distances associated with the thermally activated orientational fluctuations of the FxBA ligands in crystals 1 and 3. The increase in dielectric constant with increasing temperature, at 240 K, activated molecular fluctuation in the 3,4-F2BA ligands in crystal 3. Heat capacity measurements indicated that both the expansion and shrinkage of hydrogen bonds, and the molecular fluctuation in 3,4-F2BA ligands, contributed to phase transition, and the latter caused dipole fluctuation, resulting in a dielectric anomaly in crystal 3.

Redox-active hexakis(4-carboxyphenyl) tri(dithiolylidene)cyclohexanetrione (CPDC) was synthesized. The CPDC-based porous framework, constructed via anomalistic helical hydrogen-bonding, exhibites permanent porosity and photoconductivity.

Supramolecular cations, consisting of ethylammonium derivatives (X–CH2CH2–NH3+) complexed with [18]crown-6, were incorporated into [Ni(dmit)2]− crystals in order to promote molecular motion. Crystals of (X–CH2CH2–NH3+)([18]crown-6)[Ni(dmit)2]− (1: X = H, 2: X = F, 3: X = Cl and 4: X = Br) were prepared for this purpose. Although large amplitude molecular motions do not occur in crystal 1, dynamic disorder of F–CH2 groups takes place between two sites in crystal 2. Similar disorder of Cl–CH2 groups along with rotation of [18]crown-6 molecules also exists in crystal 3. Crystal 4 exhibits dynamic disorder of Br–CH2–CH2 groups between four sites. This is especially the case for crystal 4 which undergoes a distinct dielectric response with relaxer-like behavior in the temperature dependence of the dielectric loss tangent. Interactions between [Ni(dmit)2]− ions in all crystals are antiferromagnetic, and the magnitudes of the interactions are qualitatively consistent with the strength of intermolecular interactions estimated from transfer integrals, where interactions within [Ni(dmit)2]− dimers are the larger than the others in all crystals.

Cyclophanes featuring luminophores are considered promising candidates as thermal or mechanical stimuli-responsive luminescent materials. The mechanism of the changes in the photophysical properties on the crystal–crystal or crystal–amorphous phase transitions can be easily clarified, owing to the crystal structure of the cyclophanes. However, in the case where flexible aliphatic chains are introduced to the target cyclophane, the procurement of the crystals suitable for single-crystal X-ray analysis is challenging. Conversely, the introduction of significantly shorter linkers between large π-conjugated groups leads to difficulties in compound purification, resulting in incorrect photophysical properties, particularly in the solid state. Herein, we report the crystal structure of a 1,6-bis(phenylethynyl)pyrene-based cyclophane and mechanoresponsive luminescence. The cyclophane has a naphthalene group as another aromatic group, and the two different π-conjugated groups are bridged by tetraethylene glycol linkers. Single-crystal X-ray analysis revealed that the pyrene and naphthalene moieties form intramolecular π-stacked structures in the crystals, and intermolecular excimer formation of the luminophores was not observed. The arrangement of the isolated luminophore results in light-blue emission with a well-resolved vibronic structure in the fluorescence spectrum. Mechanical grinding induces a phase transition from crystal to amorphous, which was confirmed by the powder X-ray diffraction measurements, and the emission colour turns green. The photoluminescence spectroscopy and emission lifetime measurements clarified that the green emission is ascribed to intermolecular excimer formation. Subsequent thermal treatment recovers the initial light-blue-emissive crystalline state. The crystalline phase is thermodynamically stable, whereas the amorphous state is thermodynamically metastable.

Achieving multiple mechanoresponsive luminescence-related functions from a single molecule remains challenging. Here, we demonstrate that both two-step mechanoresponsive luminescence and the release of small guest molecules are achieved by a 9,10-bis(phenylethynyl)anthracene-based cyclophane. When gently crushed, the yellow-emissive crystal of the cyclophane exhibits a hypsochromic shift of the emission band, because of alterations in molecular packing at the surface. Subsequent grinding results in a bathochromic shift of the emission band due to excimer formation accompanying the transition from the crystalline state to an amorphous state. Another pseudopolymorph of the cyclophane exhibits the release of chloroform from its crystal structure in response to mechanical stimuli, accompanied by a photoluminescent color change from yellow-green to yellow. These results reveal that luminescent cyclophanes are promising candidates for creating sophisticated mechanoresponsive luminescent materials.

To date, proton-conducting organic crystalline materials based on crown ethers have rarely been investigated. In this work, we reveal that flexible organic 18-crown-6 derivatives with one or two 4, 40-dicarboxy-o-terphenyl (CT) groups formed four kinds of crystalline frameworks: 1CT-18C6-I (P2(1)/n), 2CT-18C6-I (P (1) over bar), 2CT-18C6-II (P (1) over bar) and 2CT-18C6-III (Cmc2(1)). Single crystal X-ray diffraction analysis clearly suggested that the water molecules were involved a hydrogen-bonded network for two frameworks. In particular, a unique one-dimensional (1D) water pathway had formed in 2CT-18C6-III and the activation energy was evaluated by Arrhenius plots to be 0.14 eV, indicating that the proton jumps from H3O+ to the neighboring H2O in the hydrogen-bonded network of 2CT-18C6-III.

Organic ferroelectrics are attracting tremendous interest because of their mechanical flexibility, ease of fabrication, and low acoustical impedance. Although great advances have been made in recent years, topological defects such as vortices remain relatively unexplored in the organic ferroelectric system. Here, from [quinuclidinium]ReO4 ([Q]ReO4), we applied the molecular design strategy of H/F substitution to successfully synthesize the organic ferroelectric [4-fluoroquinuclidinium]ReO4 ([4-F-Q]ReO4). Through H/F substitution, the Curie temperature and spontaneous polarization are respectively increased from 367 K and 5.83 μC/cm2 in [Q]ReO4 to 466 K and 11.37 μC/cm2 in [4-F-Q]ReO4. Moreover, under mechanical stress fields, three kinds of stripelike domains with various polarization directions emerge to form a windmill-like domain pattern in the thin film of [4-F-Q]ReO4, in which intriguing vortex-antivortex topological configurations can exist stably. This work provides an efficient strategy for optimizing the properties of organic ferroelectrics and exploring emergent phenomena.

The selective carbon dioxide (CO2) absorption properties of ionic liquids (ILs) are highly pertinent to the development of methods to capture CO2. Although it has been reported that fluorinated components give ILs enhanced CO2 solubilities, it has been challenging to gain a deep understanding of the interactions occurring between ILs and CO2. In this investigation, we have utilized the soft crystalline material [Cu(NTf2)2(bpp)2] (NTf2‒ = bis(trifluoromethylsulfonyl)imide, bpp = 1,3-bis-(4-pyridyl)propane) as a surrogate for single-crystal X-ray diffraction analysis to visualize interactions occurring between CO2 and NTf2‒, the fluorinated IL component that is responsible for high CO2 solubility. Analysis of the structure of a CO2-loaded crystal reveals that CO2 interacts with both fluorine and oxygen atoms of NTf2‒ anions in a trans rather than cis conformation about the S–N bond. Theoretical analysis of the structure of the CO2-loaded crystal indicates that dispersion and electrostatic interactions exist between CO2 and the framework. The overall results provide important insight into understanding and improving the CO2 absorption properties of ILs.

Li+([12]crown-4)2(TCNQ)2 (1), Li+([15]crown-5)(TCNQ)2 (2a and 2b), and Li+([18]crown-6)(TCNQ)2·(H2O)2 (3) salts (TCNQ = 7,7,8,8-tetracyano-p-quinodimethane) were prepared and examined in terms of c...

Porous materials possessing fluid spaces are of great interest in the field of material science because they have the capability of undergoing unique, external stimuli-promoted and guest uptake/rel...

A porous hydrogen-bonded organic framework (HOF) composed of N-hetero pi-conjugated molecules (N pi-HOF) is a promising candidate for multifunctional porous materials. However, such HOFs are still limited and only a handful of examples have been reported. In this study, we investigated the positional effects of annelated pyrazine rings on the structure and stability of N pi-HOFs to establish a design principle for N pi-HOFs. A new isomer of hexaazatrinaphthylene (CPBTQ) was synthesized and subjected to N pi-HOF construction, activation, and an evaluation of stability and permanent porosity. A comparison between two kinds of N pi-HOFs composed of isomers (CPBTQ and CPHATN) possessing three pyrazine rings annelated at different positions indicates that the positional difference of the pyrazine rings strongly affects the conformation of the peripheral phenylene groups, which then leads to different structures and stabilities of the N pi-HOFs. The activated N pi-HOF composed of CPBTQ (CPBTQ-1a) is revealed to exhibit a Brunauer-Emmett-Teller surface area of 471 m(2) g(-1) and shows HCl responsiveness thanks to the basic pyrazine rings annelated to the triphenylene core. We believe that the present results can contribute not only to the construction of multifunctional porous materials but also to the chemistry of heteroaromatic compounds.

Introduction of functional groups that can form intermolecular hydrogen bonds into highly-emissive luminophores is a promising way to induce mechanochromic luminescence. Herein, we report that a 9,10-bis(phenylethynyl)anthracene derivative featuring two amide groups forms green-emissive crystals based on two-dimensional hydrogen-bonded molecular sheets. Mechanical grinding changed the emission from green to yellow, owing to a transition from a crystalline to an amorphous phase. Infrared spectroscopy revealed that mechanical stimuli disrupted the linear hydrogen-bonding formation. A thermal treatment recovered the original green photoluminescence.

Metal–organic frameworks with open metal sites are promising materials for gas separations. Particularly, the M2(dobdc) (dobdc4– = 2,5-dioxidobenzenedicarboxylate, M2+ = Co2+, Mn2+, Fe2+, ...) fram...

Crystals of (HDABCO+)9(DABCO)[Ni(dmit)2]9·6CH3CN were shown to have a space group of R3[combining macron], a hexapetal flower-like channel of [Ni(dmit)2] anions, and a one-dimensional hydrogen bonding chain composed of protonated DABCO and CH3CN molecules. The crystals display antiferromagnetic and ferromagnetic interactions within and between hexamers, respectively, whereas the flexible DABCO-CH3CN array shows dielectric relaxation.

Luminescent materials that change their photophysical properties and molecular arrangement in response to external stimuli have attracted attention because of the potential application in sensors, memory, security inks, and informational displays. The combination of external stimuli-responsive luminescence with the release of volatile molecules would give more sophisticated photofunctional materials. Herein we discuss a 9,10-bis(phenylethynyl)anthracene derivative that formed green-emissive crystals containing one-dimensional toluene channels. Amide groups of the compounds formed linear hydrogen-bonds in the crystals. Thermal treatment resulted in a phase transition to another crystalline state with the release of the guest toluene molecules. However, little alteration in the photoluminescent properties occurred during the transition. Mechanical stimuli led to the release of volatile molecules along with an emission colour change with a transition from the crystalline to an amorphous phase. Infrared spectroscopy showed that linear hydrogen bonds remained after a thermal treatment-induced phase transition, whereas mechanical stimuli disturbed them.

Introducing a cyclic structure to luminophores is a promising approach for achieving external stimuli-responsive luminescence. This is because luminescent cyclophanes containing flexible linkers tend to form several molecular assembled states. However, previously reported cyclophanes exhibiting thermoresponsive and/or mechanoresponsive luminescence have not given crystals suitable for single crystal X-ray structure analysis because of the flexible cyclic molecular structures. Such analysis is important because solved crystal structures can show unambiguous correlation between the arrangement of luminophores and photophysical properties. Here, we report the crystal structure of a cyclophane featuring a 9,10-bis(phenylethynyl)anthracene group and the thermoresponsive luminescence. The cyclophane was designed with shorter flexible oligo(ethyleneglycol) chains used as linkers bridging the luminophore and another aromatic group. The two different π-conjugated groups were orthogonally arranged in the individual molecule, and the luminophores partially overlapped between adjacent molecules. The cyclophane showed a supercooled nematic phase at room temperature upon cooling. Thermal treatment for the kinetically trapped state led to a transition to another crystalline state and, consequently, a change in photoluminescence colour. Emission spectroscopic studies and emission lifetime measurements revealed that the luminophores formed excimers in the supercooled nematic phase, whereas no excimer formation was observed for the crystalline phases.

Methods relying on the use of solid solutions can be used to produce solid materials having finely controlled physical properties. In the current investigation, we utilized this protocol to prepare solid solutions derived from two different Werner complexes in order to assess the effects of component ratios on acetone vapor adsorption properties. For this purpose, microcrystalline solid solutions with the basic elemental composition α-[Cu(PF6)2(py)4]x[Cu(CF3SO3)2(py)4]1-x (x = 0.75 and 0.5) (α-PAC-2-PF6/CF3SO3(x = 0.75 and 0.5), py = pyridine) were prepared by hexane induced precipitation of acetone solutions of [Cu(PF6)2(py)4] (PAC-2-PF6) and [Cu(CF3SO3)2(py)4] (PAC-2-CF3SO3). The results of acetone sorption isotherm measurements show that gate opening and closing pressures of the solid solutions are dependent on the composition ratios of PAC-2-CF3SO3 and PAC-2-PF6. Specifically, an increase in CF3SO3- anion content induces weakening of the interactions with acetone as a consequence of expansion of lattice constants and also strengthening host-host interactions. These effects cause an increase in gate opening and closing pressures.