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Two {AsO2(OH)}-bridging lanthanide(Ln)-incorporated arsenotungstates (ATs) [H2N(CH3)2]8LnNa5 {[W3Ln2(H2O)8AsO8(OH)][B-α-AsW9O33]2}2·65H2O [Ln = ErIII (1), YbIII (2)] were synthesized by reaction of Na2WO4·2H2O, Ln(NO3)3·6H2O and NaAsO2 in the presence of dimethylamine hydrochloride. The common structural features of 1 and 2 are that the AsIII ions not only act as heteroatoms of the AT fragments but also function as the bridging groups to link two identical {[W3Ln2(H2O)8AsO8(OH)][B-α-AsW9O33]2} half-units. The results of TG analyses indicate that 1 and 2 undergo the similar three-step weight loss procedure between 25 and 800 °C. The first-step weight loss is attributable to the liberation of sixty-five lattice water molecules, the second-step weight loss corresponds to the release of sixteen coordination water molecules, ten protons as well as eight dimethylamine groups, and the third-step weight loss can be assigned to the sublimation of three As2O3 molecules. In addition, the solid-state photoluminescence properties of 1 and 2 have been investigated and mainly demonstrate the characteristic emission behaviors of ErIII ions and YbIII ions.

Three rare-earth containing docosatungstates Na 3 H 2 [RE(H 2 O) 4 ][RE(H 2 O) 5 ] 2 [W 22 O 74 H 2 ]·36H 2 O [RE = Dy III ( 1 ), Ho III ( 2 ), Y III ( 3 )] have been synthesized by reaction of Na 2 WO 4 ·2H 2 O, dimethylamine hydrochloride (DMAHC) and RE(NO 3 ) 3 ·6H 2 O in the aqueous solution and characterized by elemental analyses, IR spectra, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. 1 – 3 are isomorphous and each molecular unit consists of a S -shaped docosatungstate [W 22 O 74 H 2 ] 14 − polyoxoanion with two supporting [RE(H 2 O) 5 ] 3 + cations and one disordered [RE(H 2 O) 4 ] 3 + cation. The [W 22 O 74 H 2 ] 14 − polyoxoanion can be viewed as combination of two hendecatungstate [W 11 O 38 H] 9 − subunits in the staggered fashion by sharing two μ 2 -O atoms. The TG curves of 1 – 3 reveal the one-step weight loss between 25 °C to 700 °C. Moreover, both 1 and 2 demonstrate the characteristic luminescence emission behaviors of the corresponding RE 3 + ions and their lifetime decay curves can be well fitted to the double exponential function. In addition, the CIE chromaticity coordinates of 1 and 2 have been obtained based on their corresponding emission spectra, and their dominant wavelengths and color purities have been also calculated.

We present that the guided surface magneto-plasmons (SMPs) can be finely tailored and truely stopped at specific location in a class of non-reciprocal graded waveguide system. By examining the dispersion properties of SMPs, the one-way propagating wave stops eventually at the band edge in the proposed waveguide system, where the group velocity vanishes. Meanwhile, the stopped location can be readily tuned by an external static magnetic field. Numerical calculations on the group velocity of propagating SMPs and the spatial field distribution are employed to verify the formation of hotspots. The impact of intrinsic absorption as well as fabrication disorder involved in the realistic waveguide structure is also investigated. The results may suggest an effective method for fast modulation on wave harvesting and energy concentration through external magnetic field.

Two organic–inorganic hybrid isonicotinate-bridging lanthanide substituted phosphotungstates [H2N(CH3)2]8[Ln(H2O) (INA)(α-HPW11O39)]2·14H2O (Ln = HoШ for 1, ErШ for 2) (HINA = isonicotinic acid) have been obtained by reaction of the Na9[α-PW9O34]·16H2O precursor, Ln(NO3)3·6H2O, C2H7N·HCl and HINA in aqueous solution and structurally characterized by elemental analyses, IR spectra, single-crystal X-ray diffraction and thermogravimetric analysis. Isostructural 1 and 2 consist of one inorganic–organic hybrid dimeric {[Ln(H2O)(INA)(α-HPW11O39)]2}8 − core constituted by two symmetrically mono-Ln substituted Keggin subunits [Ln(H2O)(INA)(α-HPW11O39)]4 − bridged by two INA− ligands in the (η2,μ-1,1) fashion. Intriguingly, adjacent hybrid dimeric {[Ln(H2O)(INA)(α-HPW11O39)]2}8 − cores can be extended into a 2-D supramolecular layer via hydrogen bonding interactions. To our knowledge, 1 and 2 represent the first isonicotinate-bridging dimeric mono-lanthanide substituted phosphotungstates. Furthermore, the solid-state fluorescence properties and lifetime decay behaviors of 1 and 2 in visible and near-infrared regions have also been investigated in detail.

The hydrothermal reaction of K8Na2[A-α-GeW9O34]·25H2O, Cu(CH3COO)2·H2O, Ln(NO3)·6H2O and ethylenediamine (en) has led to a series of inorganic–organic hybrid copper–lanthanide heterometal comprising germanotungstates (GTs) [Cu(en)2(H2O)]6[Ln(H2O)(CH3COO)(α-GeW11O39)]2·8H2O [Ln = Nd3+ (1), Sm3+ (2), Eu3+ (3), Gd3+ (4), Dy3+ (5), Ho3+ (6)], which have been characterized by elemental analyses, IR spectra, thermogravimetric (TG) analyses and single-crystal X-ray diffraction. Their common feature of 1–6 is that they all comprise a CH3COO-bridging mono-Ln substituted dimeric GT fragment [Ln(H2O)(CH3COO)(α-GeW11O39)]212− with six supporting [Cu(en)2(H2O)]2+ complex cations. To the best of our knowledge, such monovacant Keggin-type GTs containing both Cu–Ln heterometal centers and mixed en and acetate ligands are very rare. The luminescence properties and the lifetime decay behavior of the solid sample of 3 have been intensively investigated at room temperature.

This review gives a brief overview on bioactivities of 8-mercaptoquinoline sulfide derivatives involving antimicrobial activity, anticancer activity, inhibitors as well as other activities. Special emphasis is given to the most recent examples.

To exploit the use of solar energy in photocatalysis, metal ion doping is one of the most effective ways. At present, atomically precise heterometallic polyoxotitanium clusters (HPTCs) are of great interest as well-defined models for the way in which metal ions are doped into bulk titanium dioxide. Recently, researchers have contributed great efforts in HPTCs where majority metal ions throughout the periodic table have successfully incorporated. The incorporation of particular characteristics of metal dopants provides the opportunity to modify the microscopic electronic structure, then optical response, and ultimate macroscopical performances. In this review, we aim to summarize the recent progress on such a rapidly evolving topic of HPTCs and provide potential theoretical models for the rational design of photocatalysts and solar energy capture. Firstly, a brief summary of the synthetic strategies and bonding models between the metals and PTCs is provided. Then clear definition and classification of the HPTCs reported up to date is given. Moreover, representative examples are illustrated from experimental, theoretical and photophysical/photochemical perspectives, particularly in light absorption, fluorescence, photocatalysis, and gas sorption etc. Finally, the main challenges and opportunities are proposed with the goal of expanding the sunlight harvesting application range of HPTCs.

Four kinds of thioether ligands (Q1–Q4) and their 21 kinds of transitional metal complexes have been synthesized, in which two new complexes have been prepared and tested. Some potential laws were obtained by comparing the pesticide activities of four kinds of ligands and their 21 kinds of transitional metal complexes based on the difference of metal ions, anions and spatial structures. The results revealed that the complexes with Ag + ion had very outstanding pesticide activities which might be related to the structure unit of a bimetallic ring and the bacteriostatic effects of anions decreased in the order Cl − > BF 4 − > ClO 4 − = CF 3 CO 2 − > CF 3 SO 3 − > NO 3 − . Compared with ligands Q1–Q4, the inhibitory effect of ligand Q1 was the best, which might be connected to the stable spatial structure.

The Mn(II) and Cd(II) complexes of an asymmetrical Schiff base ligand 4-(1H-benzimidazol-2-yl)-phenyl]-pyridin-4-methyl amine have been prepared by the method of diethyl ether diffusion. The structures of the complexes were identified by elemental analysis (EA), infrared spectra (IR) and single-crystal X-ray diffraction. It was revealed that complexes 1 and 2 were composed of discrete mononuclear structures, and formed schistose structures via two different kinds of hydrogen bonds. The antibacterial and antifungal activities of the ligand and two complexes were tested, which may provide useful information for the research and application in pharmaceutical chemicals.