Open-framework hybrid zinc/tin selenide as an ultrafast adsorbent for Cs+, Ba2+, Co2+, and Ni2.

Efficient adsorption of radioactive 137Cs+ and 60Co2+ and their decay products 137Ba2+ and 60Ni2+ bears significance for hazard elimination in case of nuclear emergency, which relies on the adsorption rate enhancement that takes advantages of compositional and structural optimization. Herein, we report a zinc-doped selenidostannate constructed from T2-supertetrahedral clusters, namely K3.4(CH3NH3)0.45(NH4)0.15Zn2Sn3Se10·3.4 H2O (ZnSnSe-1K). The soft Se and micro-porosity synergistically endow this material with a binding affinity to Cs+, Ba2+, Co2+, and Ni2+ ions and ultrafast kinetics with R > 97.6% in 2-60 min. In particular, ZnSnSe-1K can remove 99.34% of Cs+ in 2 min (KdCs > 1.5 × 105 mL g-1), contributing to a record rate constant k2 of 9.240 g mg-1 min-1 that surpasses all metal chalcogenide adsorbents. ZnSnSe-1K exhibits good acid/base tolerance (pH = 0-12), and the adsorption capacities at neutral are 253.61 ± 9.15, 108.94 ± 25.32, 45.76 ± 14.19 and 38.49 ± 2.99 mg g-1 for Cs+, Ba2+, Co2+, and Ni2+, respectively. The adsorption performances resist well co-existing cations and anions, and the removal rates can keep above or close to 90% even in sea water. ZnSnSe-1K is employed in continuous column and membrane filtration, both of which shows excellent elimination efficiency (R > 99%) for mixed Cs+, Ba2+, Co2+, and Ni2+. Especially, the membrane with an ultrathin (70 µm) ZnSnSe-1K layer can remove 97-100% Cs+ in suction filtration with a short contact time of 0.33 s. Combined with the simple synthesis, facile elution and great irradiation resistance, ZnSnSe-1K emerges as a selenide adsorbent candidate for use in environmental remediation especially that involving nuclear waste disposal.

Risk measurement and application of the international carbon market in the era of global conflict: A data-driven study using FCM.

The accurate measurement and effective estimation of carbon market risk are crucial for practitioners and policymakers to mobilize resources toward the transition to a climate-resilient economy, particularly in a new era of global conflict. However, existing studies that have explored factors contributing to carbon market risk primarily relied on experience or subjective judgment in selecting risk-related factors. Such approaches undermine the estimation accuracy while making it difficult to ascertain causal inferences related to the risk spillover. To fill the gap, we adopted a data-driven factor analysis strategy by introducing the Fuzzy Cognitive Maps (FCM) model to establish a carbon market network and identify risk-related factors. We then evaluate the carbon market's risk level and spillover effects using combined econometric methods and explore their application in portfolio management. We report three main findings. First, based on our sample of 3217 observations between 2008 and 2022, five factors influencing carbon market risk emerged from the FCM, including OIL, COAL, SP500ENERGY, SPCLEANENERGY, and GPR. Second, we find a notable rise in risk spillover from GPR to EUA during the Russia-Ukraine conflict and an escalation of total cross-market spillover during extreme events. Third, our study presents new evidence on the hedging effect for EUA of the SP500ENERGY before the Russia-Ukraine conflict and of the SPCLEANENERGY during the conflict. Finally, implications are discussed for policymakers and investors.

CSI-based sliding window fingerprinting method tailored for a signal blocking environment in VLP systems.

In visible light indoor positioning systems, the localization performance of the received signal strength (RSS)-based fingerprinting algorithm would drop dramatically due to the occlusion of the line-of-sight (LOS) signal caused by randomly moving people or objects. A sliding window fingerprinting (SWF) algorithm based on channel state information (CSI) is put forward to enhance the accuracy and robustness of indoor positioning in this work. The core idea behind SWF is to combine CSI with sliding matching. The sliding window is used to match the received CSI and the fingerprints in the database twice to obtain the optimal matching value and reduce the interference caused by the lack of the LOS signal. On this premise, in order to reflect the different contributions of various paths in CSI to the calculation of match values, a weighted sliding window fingerprinting (W-SWF) is also proposed for the purpose of further improving the accuracy of fingerprint matching. A 4 m × 4 m × 3 m indoor multipath scene with four LEDs is established to evaluate the positioning performance. The simulation results reveal that the mean errors of the proposed method are 0.20 cm and 1.43 cm respectively when the LOS signal of 1 or 2 LEDs is blocked. Compared with the traditional RSS algorithm, the weighted k-nearest neighbor (WKNN) algorithm, and the adaptive residual weighted k-nearest neighbor (ARWKNN) algorithm, the SWF algorithm achieves over 90% improvement in terms of mean error and root mean square error (RMSE).

M-Sn-Q (M = Zn, Cd; Q = S, Se) Compounds Templated by (Alkyl)ammonium Species: Synthesis, Crystal Structure, and Sr2+ Adsorption Property.

Deep investigations on the synthetic and structural chemistry of heterometallic chalcogenidostannates bear fundamental significance for the establishment of the structure-property relationship that would offer guidance on the functional material innovation. Presented here are four ammonium- and/or alkylammonium-directed M-Sn-Q (M = Zn, Cd; Q = S, Se) compounds, namely, [NH4]7[H3O]3Zn4Sn4S17 (1), [NH4]5[(CH3)2NH2]Zn4Sn5S17 (2), [CH3CH2NH3]22Zn16Sn12Se51(H2O)4·16H2O (3), and [NH4]2CdSnSe4 (4). All four compounds were synthesized in deep eutectic solvents (DESs) or ethylamine aqueous solution, both of which function simultaneously as reaction media and structure-directing agents. Compound 1 consists of discrete P1-[Zn4Sn4S17]10- clusters templated by mixed [NH4]+/[H3O]+ cations. In compound 2, such P1 clusters are bridged by Sn4+ ions in a 4,4-connection mode to form a [Zn4Sn5S17]n6n- framework with three types of cavities (I-III) varying in size. The two smaller cavities (I and II) accommodate NH4+ while the larger one(III) is occupied by [(CH3)2NH2]+, reflecting the rational size-dependence of cations on cavities. Compound 3 features an [Zn16Sn12Se51(H2O)4]n22n- open framework constructed from the 4,3-connection of P1-[Zn4Sn4Se17]10- clusters and {Zn(H2O)}2+ bridges. This linkage mode contributes to a large cage-like subunit (inner dimension: 21.99 × 9.06 Å2) and therefore an ultrahigh porosity that are occupied by [CH3CH2NH3]+ cations and water molecules (volume fraction: 57.7%). Compound 4 exists as a stacking of [CdSnSe4]n2n- chains, which are composed of alternatively arranged {CdSe4} and {SnSe4} tetrahedra, in combination with [NH4]+ cations as both charge-compensating and space-filling agents. Detailed synthetic, structural, and topological analyses were performed on these solid materials, coupled with extensive investigations on their optical and thermal properties. Compound 3 exhibits an efficient Sr2+ adsorption performance, featuring ultrafast kinetics (94.69% in 5 min), high removal rate (98.57% in 20 min) at equilibrium, and high capacity (104.17 ± 23.53 mg g-1).

A gradient Sn4+@Sn2+ core@shell structure induced by a strong metal oxide-support interaction for enhanced CO2 electroreduction.

Oxidation states of Sn in tin oxides are hard to regulate due to the uncontrollable evolution during the electrochemical CO2 reduction reaction (CO2RR), thus limiting the adsorption capabilities and reaction kinetics. Herein, we propose a metal oxide-support interaction-mediated strategy to modify the electronic properties of tin oxides. A gradient Sn4+@Sn2+ core@shell structure was formed as a result of electron transfer from g-C3N4 to anchored SnO2, unlike reduced graphene oxide (rGO)-supported SnO2 with Sn4+-rich surfaces. Such unique structures were revealed by the depth profiles of X-ray photoelectron spectra, and they enhanced the adsorption and stabilization of the *CO2˙- intermediate and accelerated the reaction kinetics. Consequently, SnO2/g-C3N4 delivered a faradaic efficiency of 95.1% for the C1 products at -1.06 V, exceeding those of SnO2/rGO and most reported catalysts. Moreover, the performances were sustained for 70 h without obvious degradation. This work offers an alternative route to efficient catalyst design by combining oxidation state regulation and metal oxide-support interaction and contributes to the development of sustainable technologies for achieving carbon neutrality.

Tailoring Hybrid Aluminoborate Frameworks by Incorporating Multicomponent Cadmium-Amine Complexes with Various Conformations.

Inorganic-organic hybrid aluminoborates represent a subclass of porous materials, which rely on effective construction method and structure-directing agents. Herein, we prepared a series of hybrid aluminoborates through covalent decoration of unsaturated Cd2+ complexes, whose formation take advantage of chelating amine and long-chain diamine as mixed ligands. These isolated compounds, that is, [Cd(en)(1,4-dab)0.5][AlB5O10] (1a; its analogue with discrete complex [Cd(en)(dien)H2O][AlB5O10] is denoted as 1b), [Cd(1,2-dap)1.5(1,4-dabH)0.5]{Al[B5O8(OH)2](B5O10)0.5} (2), and [Cd(en)(1,3-dap)][AlB5O10] (3) feature open frameworks (1a, 1b, and 3) or a sandwich-like porous layer (2) that are constructed by AlO4 tetrahedra and [B5O10]5-/[B5O8(OH)2]3- clusters. However, they exhibit different structural features in interconnection, channel environment, and topology as a result of diversified interactions between unsaturated complexes and aluminoborate frameworks, that is, through forming two Cd-O bonds with (i) a pair of neighboring BO3 and AlO4, (ii) the same AlO4, or (iii) the same BO3. The variation in connection mode exerts essential influence on binding effects and steric hindrance that are reflected by changes in interatomic distance, bond angle, window configuration, and interlinkage of units. In addition, the incorporation of unsaturated Cd2+ complexes endows these aluminoborate materials with photoluminescence function. Compound 3 with a noncentrosymmetric structure exhibits second harmonic generation (SHG) response approximately 0.7 times that of KDP. The preparation strategy for hybrid aluminoborates proposed here combines well molecular design with templating assembly, whose synergistic effect would be crucial for drawing a rational pathway for inorganic synthesis, especially with focus on structural and functional innovation.

RSS-based visible light positioning based on channel state information.

As a result of the influence of indoor multipath effects, visible light positioning (VLP) technology based on the received signal strength (RSS) has difficulty providing stable and highly accurate position estimation. In order to cope with this challenge, a trilateration-based positioning method using channel state information (CSI) is proposed. Two algorithms that can estimate the number of channel paths are studied, which are the prerequisites for the obtaining of an accurate ratio of received power of the line-of-sight (LOS) path to total received power. Unlike traditional trilateration positioning methods where total received power is used, the proposed method introduces CSI as a means of estimating the received power of the LOS path, which it uses for ranging. By reducing interference from the reflected paths in the received power, the proposed method has high-precision and high-reliability positioning capabilities. The positioning performance of the proposed method in an indoor environment with four LED bulbs and a single photodetector (PD) is evaluated through simulation. The simulation results demonstrate that the proposed method provides an average accuracy of 6.1 cm and a maximum positioning error of 17.7 cm in a cubic space with a size of 4 m×4 m×3 m. Compared to the existing least-squares (LS) method that uses total received power, the new method achieves approximately 83% improvement in the mean error of positioning and 81% in root mean square error (RMSE).

Efficient removal of Ba2+, Co2+ and Ni2+ by an ethylammonium-templated indium sulfide ion exchanger.

Removal of radioactive 133Ba, 60Co and 63Ni and their nonradioactive isotopes through ion exchange method would be highly beneficial for the safe disposal of liquid industrial waste, and it also bears importance for the emergency response to nuclear accident. Herein, we report the employment of an indium sulfide [CH3CH2NH3]6In8S15 (InS-2) with exchangeable ethylammonium cations for efficient and selective uptake of Ba2+, Co2+ and Ni2+. The corner-sharing linkage of P1-{In8S17} clusters in InS-2 endow the layered structure with nanoscale windows, which facilitates both transfer and accommodation of the large hydrated divalent metal ions. This results in ultrafast exchange kinetics (10-20 min) and top-level exchange capacities of 211.73 mg g-1 for Ba2+, 103.57 mg g-1 for Co2+, and 111.78 mg g-1 for Ni2+. Particularly, InS-2 achieves ultrahigh Kd values of 2.3 × 105 mL g-1 for Ba2+, 2.0 × 105 mL g-1 for Co2+ and 1.6 × 105 mL g-1 for Ni2+, corresponding to remarkable removal efficiencies larger than 99.4% (C0 ~ 6 ppm). InS-2 shows high ß and γ irradiation resistance, wide pH durability (pH 3-13 for Ba2+, pH 3-11 for Co2+ and Ni2+), and outstanding selectivity against competitor ions (e.g. Na+, K+, Mg2+, Ca2+). The InS-2-filled ion exchange column exhibits a fantastic removal effect (R > 99%) for mixed Ba2+, Co2+, Ni2+, as well as Sr2+. The ultralong column-treatment on 20000 BVs of flow reveals an affinity order of Co2+ > Ni2+ > Ba2+ > Sr2+ for InS-2, which gives deep insights into the adsorption process and interaction between competitor ions. This excellent uptake of Ba2+ (Ra by analogy), Co2+ and Ni2+ ions by InS-2 highlights the great potential of metal chalcogenides as a type of promising materials for minimizing contamination in complex wastewater.

Mixed Solvothermal Synthesis of Tn Cluster-Based Indium and Gallium Sulfides Using Versatile Ammonia or Amine Structure-Directing Agents.

Metal chalcogenide supertetrahedral Tn clusters are of current interest for their unique compositions and structures, which rely highly on the structure-directing agents. Herein, we report four novel Tn cluster-based indium and gallium sulfides, namely, [NH(CH3)3]4In4S10H4 (1), (NH3)4Ga4S6 (2), [NH3CH2CH3]5(NH2CH2CH3)2Ga11S19 (3), and [NH3CH2CH2OH]6Ga10S18·2NH2CH2CH2OH (4). All four compounds were solvothermally synthesized in mixed amine-ethanol solutions or deep eutectic solvent (DES), where ammonia/amine molecules play significant structure-directing roles in the speciation and crystal growth. (1) Being protonated, the trimethylamine and ethanolamine molecules surround the T2-[In4S10H4]4- clusters (for 1) and [Ga10S18]n6n- open framework (for 4), respectively, compensating for the negative charge of the inorganic moieties. (2) With the lone pair of electrons, the ammonia molecules in 2 coordinate directly to corner Ga3+ ions of the {Ga4S6} cage to give a neutral T2-(NH3)4Ga4S6 cluster. (3) For compound 3, part of the ethylamine molecules act as terminating ligands for the T1 and T3 units in the [Ga11S19(NH2CH2CH3)2]n5n- layer, while the rest act as interlamellar countercations upon protonation. Theoretical studies reveal the contributions of N, C, and H to the density of states (DOS) for 2 and 3 because of their hybrid structures that combine the ammonia/amine ligands with sulfide moieties together.

Removal of Sr2+ Ions by a High-Capacity Indium Sulfide Exchanger Containing Permeable Layers with Large Pores.

An ethylammonium-templated indium sulfide, [CH3CH2NH3]6In8S15 (InS-2), featuring anionic layers perforated with large, 24-membered rings that facilitate the accommodation of hydrated Sr2+ ions is reported. InS-2 exhibits an excellent adsorption performance toward Sr2+ with a top-ranked capacity (qm = 143.29 mg g-1), rapid kinetics, wide pH durability (3-14), ß- and γ-radiation resistances, and a facile elution.

Efficient Cs+-Sr2+ Separation over a Microporous Silver Selenidostannate Synthesized in Deep Eutectic Solvent.

Efficient Cs+-Sr2+ separation, highly desirable for radionuclide recovery in medical and industrial applications, was achieved by the ion exchange technique over a novel microporous silver selenidostannate, [NH3CH3]0.5[NH2(CH3)2]0.25Ag1.25SnSe3 (AgSnSe-1). This material was synthesized in deep eutectic solvent (DES), where the alkylammonium cations play significant structure-directing roles in the construction of micropores that allow for selective ion exchange toward Cs+ against Sr2+. The much greater KdCs (1.06 × 104 mL g-1) over KdSr (87.7 mL g-1) contributes to an outstanding separation factor SFCs/Sr of ∼121.4 that is top-ranked among inorganic materials. An ion exchange column filled with AgSnSe-1 exhibits a remarkable separation effect for 10 000 bed volumes of continuous flow, with removal rates of ∼99.9% and ∼0 ± 5.5% for Cs+ and Sr2+, respectively. AgSnSe-1 exhibits excellent ß and γ radiation resistances and a chemical stability over a broad pH range of 1-12. The Se leaching level below the safe guideline value for drinking water highlights the environmental-friendly nature of AgSnSe-1. The high Cs+ exchange performance is almost unaffected by Na+, Mg2+, and Ca2+ cations. The Cs+-laden product AgSnSe-1Cs can be facilely eluted for recycling use, highlighting the great potential of open framework metal selenides in nuclear waste treatment and renewable energy utilization.

Di-lacunary [In6S15]12- cluster: the building block of a highly negatively charged framework for superior Sr2+ adsorption capacities.

In this study, the construction of a highly negatively charged layered material [CH3CH2NH3]6In6S12 (InS-1) by introducing a lacunary cluster as the building block is reported. The pronounced framework negative charge density (5.59 × 10-3) and the soft Lewis basic S component endow InS-1 with an effective ion exchange performance toward heavier Sr2+, with a top-level adsorption capacity qm of 105.35 mg g-1. InS-1 exhibits a good exchange activity over pH 3-12, and the Sr2+-laden product can be facilely eluted.

Deep eutectic solvothermal synthesis of an open framework copper selenidogermanate with pH-resistant Cs+ ion exchange properties.

Presented here is the deep eutectic solvothermal synthesis of an open framework copper selenidogermanate, namely [NH3CH3]0.75Cu1.25GeSe3 (CuGeSe-1), which exhibits a rapid and effective Cs+ ion exchange performance (qm = 225.3 mg g-1). CuGeSe-1 shows a structural flexibility upon Cs+ exchange. The robust selenide-based framework contributes to an excellent pH stability (1-12). The Cs+-laden product could be facilely eluted.

Stepwise Conversion from GeO2 to [MGe4S10]n3n- (M = Cu, Ag) Polymer via Isolatable [Ge2S6]4- and [Ge4S10]4- Anions by Virtue of Templating Technique.

Rational synthesis of inorganic matter remains a great challenge encountered with modern synthetic chemistry. Here we reported the stepwise solvothermal conversion from GeO2 to [MGe4S10]n3n- (M = Cu, Ag) polymer via isolatable [Ge2S6]4- and [Ge4S10]4- anions by virtue of templating technique. The facile sulfuration of GeO2 resulted in the methylammonium-templated dimeric thiogermanate [CH3NH3]4Ge2S6 (1). This was used subsequently as a precursor for the formation of adamantane-like [Ge4S10]4- cluster, which was isolated as a mixed methylammonium/ethylammonium salt [CH3CH2NH3]3[CH3NH3]Ge4S10 (2). Compound 2 was then successfully used as a precursor to react with Cu+ and Ag+ cations in the presence of tetraethylammonium, resulting in alternating copolymeric products [(CH3CH2)4N]3MGe4S10 (M = Cu (3), Ag (4)), whose anionic moieties feature a novel zigzag chainlike structure constructed by [Ge4S10]4- clusters via two-coordinate Cu+/Ag+ linkers. Mixed amine/ethanol or deep eutectic solvents were applied as media for the syntheses of 1-4, and all the products were characterized in the solid state and solution. Crystal structural analysis of the title compounds revealed significant templating roles of the alkylammonium cations as both space-filling agents and hydrogen-bonding donors, suggesting the structure-directing mechanism for the species formation and crystal growth. The design and optimization of multistep structural conversion upon templating effects would be beneficial for drawing rational, predictable pathways for inorganic synthesis.

Effective and Rapid Adsorption of Sr2+ Ions by a Hydrated Pentasodium Cluster Templated Zinc Thiostannate.

Separation of 90Sr from radioactive wastewater not only is essential for human public health and environmental remediation but also bears importance for alternate medical and industrial applications. Here, we report the facile synthesis of an open framework zinc thiostannate, Na5Zn3.5Sn3.5S13·6H2O (ZnSnS-1), templated by hydrated pentasodium clusters. This compound exhibits an effective and rapid ion exchange property for Sr2+ ions. The exchange kinetics conforms to a pseudo-second-order model, implying that the chemical adsorption of Sr2+ may be the rate-determining step. According to the Langmuir-Freundlich isotherm, the maximum exchange capacity of ZnSnS-1 for Sr2+ is 124.2 mg/g and ranks ahead of those of all the reported metal sulfide Sr2+ adsorbents. High exchange performance is observed over the broad pH range 2.5-13, although it could be inhibited to some extent by coexisting ions, especially Na+ and Ca2+. ZnSnS-1 shows a higher affinity for Sr2+ compared to Cs+, and the performance is almost unaffected by the presence of coexisting Cs+ even in excess amounts. Importantly, the Sr2+ in the exchanged product can be conveniently eluted by a concentrated KCl solution, and the recycled exchanger can be further used for Sr2+ exchange. These advantages combined with the robust framework for recycling concerns make ZnSnS-1 a highly promising exchanger for removal of radioactive Sr from the liquid nuclear waste.

Selenidostannates and a Silver Selenidostannate Synthesized in Deep Eutectic Solvents: Crystal Structures and Thermochromic Study.

Deep eutectic solvents (DESs) have been adopted as reaction media for solvothermal synthesis of crystal materials. In the present work, we extended the scope of DESs in chalcogenidometalate preparation by including dimethylamine, ethylamine, and trimethylamine hydrochlorides and synthesized a series of novel Sn-Se and Ag-Sn-Se compounds: i.e., [NH2(CH3)2]2Sn3Se7·0.5NH(CH3)2 (1), [NH4]2Sn4Se9 (2), [NH3C2H5]2Sn3Se7 (3), and [NH4]3AgSn3Se8 (4). Compounds 1 and 3 possess honeycomb lamellar [Sn3Se7] n2 n- structures featuring large hexagonal windows, while compound 2 features a rare [Sn4Se9] n2 n- anionic layer consisting of tetrameric {Sn4Se10} clusters as secondary building units (SBUs). Compound 4 comprises infinite [AgSn3Se8] n3 n- chains built by {Sn3Se8} units with Ag+ linkers, and it represents the first heterometallic chalcogenide synthesized in DESs. The organic ammonium cations of halide salts or in situ formed ammonium cations from the decomposition of urea act as templating agents for the formation of the inorganic frameworks. Compound 4 exhibits a marked thermochromic performance in the visible light range owing to the negative temperature dependence of its band gap ( Eg = 2.305-2.119 eV in the range of 100-450 K). The gold-dark red-gold color change is highly reversible in five rounds of heating and cooling, without any phase transition of the material, shedding light on the consequent device innovations.

Preparation of thermochromic selenidostannates in deep eutectic solvents.

Deep eutectic mixtures were deployed for the preparation of porous layered [Sn3Se7]n2n- single crystals. The perforation on the layers accentuates the negative temperature dependence of its band gap, resulting in remarkable thermochromic performance. Substitution of the hydroxo group by the methyl group provides an enhanced hydrophobicity for the organic template, leading to an anhydrous product with a remarkably improved thermal stability and thus reversible thermochromic properties.

Combination of Metal Coordination Tetrahedra and Asymmetric Coordination Geometries of Sb(III) in the Organically Directed Chalcogenidometalates: Structural Diversity and Ion-exchange Properties.

Chalcogenidometalates exhibit rich and diverse structures and properties applicable to ion exchange, thermoelectrics, photocatalysis, nonlinear optics, and so on. This personal account summarizes our recent progress in constructing chalcogenidometalates by combining metal coordination tetrahedra and the asymmetric coordination geometries of Sb(3+) in the presence of organic species (typically organic amines and metal-organic amine complexes), which has been demonstrated as an effective strategy for synthesizing chalcogenidometalates with diversified structures and interesting properties. The linkage modes of asymmetric SbQn (n = 3, 4) geometries and group 13 (or 14) metal coordination tetrahedra are analyzed, and the secondary building units (SBUs), with different compositions and architectures, are clarified. The crucial role and function of organic species in the formation of chalcogenidometalates are explored, with an emphasis on their powerful structure-directing features. In particular, some chalcogenidometalates in this family exhibit excellent ion-exchange properties for Cs(+) and/or Sr(2+) ions; the factors affecting ion-exchange properties are discussed to understand the underlying ion-exchange mechanism.

Ln12 -Containing 60-Tungstogermanates: Synthesis, Structure, Luminescence, and Magnetic Studies.

A new class of hexameric Ln12 -containing 60-tungstogermanates, [Na(H2 O)6 ⊂Eu12 (OH)12 (H2 O)18 Ge2 (GeW10 O38 )6 ](39-) (Eu12 ), [Na(H2 O)6 ⊂Gd12 (OH)6 (H2 O)24 Ge(GeW10 O38 )6 ](37-) (Gd12 ), and [(H2 O)6 ⊂Dy12 (H2 O)24 (GeW10 O38 )6 ](36-) (Dy12 ), comprising six di-Ln-embedded {ß(4,11)-GeW10 } subunits was prepared by reaction of [α-GeW9 O34 ](10-) with Ln(III) ions in weakly acidic (pH 5) aqueous medium. Depending on the size of the Ln(III) ion, the assemblies feature selective capture of two (for Eu12 ), one (for Gd12 ), or zero (for Dy12 ) extra Ge(IV) ions. The selective encapsulation of a cationic sodium hexaaqua complex [Na(H2 O)6 ](+) was observed for Eu12 and Gd12 , whereas Dy12 incorporates a neutral, distorted-octahedral (H2 O)6 cluster. The three compounds were characterized by single-crystal XRD, ESI-MS, photoluminescence, and magnetic studies. Dy12 was shown to be a single-molecule magnet.

Ti2-Containing 18-Tungsto-2-Arsenate(III) Monolacunary Host and the Incorporation of a Phenylantimony(III) Guest.

The novel Ti2-containing, sandwich-type 18-tungsto-2-arsenate(III) [(Ti(IV)O)2(α-As(III)W9O33)2](14-) (1) was successfully synthesized by the reaction of [TiO](2+) species with [α-As(III)W9O33](9-). The monolacunary polyanion 1 is solution-stable, and a further reaction with 1 equiv of phenylantimony(III) dichloride resulted in [C6H5Sb(III)(Ti(IV)O)2(α-As(III)W9O33)2](12-) (2). Both polyanions 1 and 2 were structurally characterized in the solid state and solution. Electrochemical studies were also performed on both polyanions.