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In this study, we investigated reversible intermolecular proton shifting (IPS) coupled with spin transition (ST) in a novel FeII complex. The host FeII complex and the guest carboxylic acid anion were connected by intermolecular hydrogen bonds (IHBs). We extended the intramolecular proton transfer coupled ST phenomenon to the intermolecular system. The dynamic phenomenon was confirmed by variable‐temperature single‐crystal X‐ray diffraction, neutron crystallography, and infrared spectroscopy. The mechanism of IPS was further validated using density functional theory calculations. The discovery of IPS‐coupled ST in crystalline molecular materials provides good insights into fundamental processes and promotes the design of novel multifunctional materials with tunable properties for various applications, such as optoelectronics, information storage, and molecular devices. [ABSTRACT FROM AUTHOR]

Some cyanide‐bridged complexes are known for exhibiting slow magnetic relaxation behavior in a light‐induced metastable state. Herein, an unexpected reverse effect is observed for the first time in the S=1/2 {FeIILS‐CoIIILS‐FeIIILS} (HS=high spin, LS=low spin) ground state of a novel V‐shaped trinuclear cyanide‐bridged {Fe2Co} complex. In this complex, light‐switchable iron‐cobalt charge transfer with repeatable off/on switching of slow magnetic relaxation is discovered upon alternating laser irradiation at 785 and 560 nm. An important characteristic of the present compound is that the S=1/2 ground state exhibits slow magnetic relaxation before irradiation, whereas this is accelerated after irradiation. This is different from the typical behavior, where the light‐induced metastable state exhibits slow magnetic relaxation. [ABSTRACT FROM AUTHOR]

Two new lanthanide metal–organic frameworks Ln(FBPT)(H2O)(DMF) (FBPT = 2′-fluoro-biphenyl-3,4′,5-tricarboxylate, Ln = Eu and Tb) were prepared under solvothermal conditions. Single crystal X-ray diffraction analyses reveal that the two compounds are isostructurally related with the same one-dimensional channel structure on the basis of FBPT as an organic linker. Herein, the Eu(FBPT)(H2O)(DMF) (EuL) is selected as a representative sample for luminescent measurements. Study of the photoluminescence properties reveals that the EuL exhibits red emission, corresponding to the 5D0→7FJ (J = 1–4) transitions of the Eu3+ ion under UV light excitation. Most interestingly, when this compound was immersed in the different organic solvents and metal ion DMF solutions, it shows highly selective and sensitive sensing for small organic molecules and Cu2+ ions. In connection to this, a probable sensing mechanism was also discussed in this paper. [ABSTRACT FROM AUTHOR]

A series of lanthanide anionic metal–organic frameworks,[NH2(CH3)2][Ln(MDIP)(H2O)] (Ln = Pr (1), Nd (2), Sm (3), Eu (4), Gd (5), Tb (6),Dy (7); H4MDIP = methylenediisophthalic acid)and [NH2(CH3)2][Ln(MDIP)(H2O)]·0.5NH(CH3)2(Ln = Er (8), Tm (9), Yb (10)), have been synthesizedand characterized. In compounds 1–7, the adjacent Ln3誉 are intraconnected to form infinitemetal-carboxylate oxygen chain-shaped building blocks along the [001]direction. In compounds 8–10, MDIPligands bridge dinuclear lanthanide centers to form three-dimensionalframeworks which can be rationalized as a (4,8)-connected topologicalnet with the Schläfli symbol of (410.614.84)(45.6)2. Dimethylamine cationsoccupy the vacancy of all the compounds as counterions. The photophysicalproperties of trivalent Pr, Nd, Sm, Eu, Tb, Dy, Er, Yb compounds atroom temperature were investigated and showed that MDIP is an efficientsensitizer of the luminescence of both the Tb3誉 emittingvisible light and the Yb3誉 emitting in the near-IR.Antiferromagnetic interactions between Gd3誉 were observedfrom magnetic susceptibility data. [ABSTRACT FROM AUTHOR]

Five new three/two-fold interpenetrated coordination polymers, namely, [Cd(mfda)(L1)] (1), [Cd(efda)(L1)] (2), [Zn2(mfda)2(L2)]·DMF·H2O (3), [Zn2(efda)2(L2)]·(DMF)0.25, (4) and [Cd2(mfda)2(L2)2]·DMF·H2O (5) (H2mfda = 9,9-dimethylfluorene-2,7-dicarboxylic acid, H2efda = 9,9-diethylfluorene-2,7-dicarboxylic acid, L1= Methylene bis(3,5-dimethylpyrazole) and L2= 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene), have been synthesized under solvent-thermal conditions with mixed ligands. Compounds 1and 2are isostructural and possess two-dimensional (6, 3) layered structures containing two kinds of rings. Three equivalent (6, 3) net interpenetrate in a parallel fashion to form an unprecedented mat-like 2D sheet. Compounds 3and 4are almost identical in structure and display threefold interpenetrating α–Po net structures. Compound 5displays a twofold interpenetrated 3D 6-connected net with α–Po topology. The luminescent properties of these compounds have been studied in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

Yttrium fluoride sub-microflowers were synthesized by facile hydrothermal route without using any expensive or environmental unfriendly agents. The influences of various hydrothermal parameters on the final products were investigated. It was found that the concentration of NH3·H2O had a significant effect on the morphology change of YF3sub-microcrystals. The growth mechanism of the as-obtained YF3sub-microflowers was proposed. The multicolor upconversion (UC) photoluminescence (PL) was successfully realized in Yb3+/Tm3+, Yb3+/Ho3+and Yb3+/Er3+doped YF3sub-microflowers when excited by 980 nm laser diode (LD). The pumping power dependence of the fluorescent intensity is investigated to understand the fundamental UC mechanism. [ABSTRACT FROM AUTHOR]

High-quality Y6O5F8/YF3microcrystals have been synthesised by using a hydrothermal and subsequent calcination route. Upon changing the initial solution pH value, the as-prepared microcrystal can be well tuned from YF3octahedron microcrystals to YF3hollow spheres and finally to Y6O5F8microtubes. The as-obtained microcrystals have been characterised by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and photoluminescence (PL) spectra. When the Y6O5F8:Ln3+microtubes are excited by a 980 nm continual wave laser diode, bright red, green, and blue room temperature upconversion PL emissions have been observed. A series of white light emissions have been obtained by precisely adjusting dopants concentration in Y6O5F8microtubes. [ABSTRACT FROM AUTHOR]

The first near-infrared luminescent ytterbium metal–organic framework has been realized for the highly selective and sensitive sensing of small molecules. [ABSTRACT FROM AUTHOR]

Abstract: Well-defined Sb2S3 microspheres consisted of many small nanoparticles were synthesized via a simple one-pot hydrothermal process. On the basis of a series of contrast experiments, the probable growth mechanism and fabrication process of the products were proposed. The optical properties of the products were studied as well and the results demonstrated that the products presented blue luminescence related to the corresponding microstructure. In addition, we firstly verified that the Sb2S3 microspheres could store hydrogen electrochemically, and a discharge capacity of 101 mA h g−1 was measured under normal atmosphere at room temperature. [Copyright &y& Elsevier]

Abstract: Uniform In2S3 octahedron-built microspheres were synthesized by using a mild hydrothermal treatment in the presence of L-glutamic acid at 180°C. The microsphere with an average size of 5μm was composed of interconnected octahedrons with diameters in the range from 100 to 150nm. The products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and X-ray photoelectron spectroscopy (XPS). The synthesis of various hollow and solid sphere structures and flower structures was achieved using different amino acids. This is the first report on synthesizing In2S3 nanostructures using different amino acids to modulate the morphology of the final products. Primary photoluminescence studies on the prepared In2S3 microspheres show promising results. [Copyright &y& Elsevier]

In this study, we investigated reversible intermolecular proton shifting (IPS) coupled with spin transition (ST) in a novel Fe II complex. The host Fe II complex and the guest carboxylic acid anion were connected by intermolecular hydrogen bonds (IHBs). We extended the intramolecular proton transfer coupled ST phenomenon to the intermolecular system. The dynamic phenomenon was confirmed by variable-temperature single-crystal X-ray diffraction, neutron crystallography, and infrared spectroscopy. The mechanism of IPS was further validated using density functional theory calculations. The discovery of IPS-coupled ST in crystalline molecular materials provides good insights into fundamental processes and promotes the design of novel multifunctional materials with tunable properties for various applications, such as optoelectronics, information storage, and molecular devices., (© 2024 Wiley-VCH GmbH.)

The crystallization of a complex having electron transfer properties in a polar space group can induce the polarization switching of a crystal in a specific direction, which is attractive for the development of sensors, memory devices, and capacitors. Unfortunately, the probability of crystallization in a polar space group is usually low. Noticing that enantiopure compounds crystallize in Sohncke space groups, this paper reports a strategy for the molecular design of non-ferroelectric polarization switching crystals based on the use of intramolecular electron transfer and chirality. In addition, this paper describes the synthesis of a mononuclear valence tautomeric (VT) cobalt complex bearing an enantiopure ligand. The introduction of enantiomer enables the crystallization of the complex in the polar space group (P2 1 ). The polarization of the crystals along the b-axis direction is not canceled out and the VT transition is accompanied by a change in the macroscopic polarization of the polar crystal. Polarization switching via electron transfer is realized at around room temperature., (© 2022 Wiley-VCH GmbH.)

Some cyanide-bridged complexes are known for exhibiting slow magnetic relaxation behavior in a light-induced metastable state. Herein, an unexpected reverse effect is observed for the first time in the S= 1 / 2 {Fe II LS -Co III LS -Fe III LS } (HS=high spin, LS=low spin) ground state of a novel V-shaped trinuclear cyanide-bridged {Fe 2 Co} complex. In this complex, light-switchable iron-cobalt charge transfer with repeatable off/on switching of slow magnetic relaxation is discovered upon alternating laser irradiation at 785 and 560 nm. An important characteristic of the present compound is that the S= 1 / 2 ground state exhibits slow magnetic relaxation before irradiation, whereas this is accelerated after irradiation. This is different from the typical behavior, where the light-induced metastable state exhibits slow magnetic relaxation., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)