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Three chiral [Eu2Ti4] enantiomers with circularly polarized luminescence (CPL) characteristics were synthesized. The quantum yields and luminescence lifetimes were regulated by switching various carboxylate ligands.

Hybrid organic-inorganic halide perovskites (HOIPs) have received continued interest for their structure diversity and potential application in optoelectronic, solar cells, nonlinear optics (NLO), and ferroelectrics. Structural symmetry breaking induced by water molecules in single-crystal-to-single-crystal (SCSC) transformations is beneficial to develop ferroelectrics or second-harmonic generation (SHG) materials. Along this line, a water-containing two-dimensional (2D) double perovskite, (C

A molecular tweezer

Hundreds of members have been synthesized and versatile applications have been promised for endofullerenes (EFs) in the past 30 y. However, the formation mechanism of EFs is still a long-standing puzzle to chemists, especially the mechanism of embedding clusters into charged carbon cages. Here, based on synthesis and structures of two representative vanadium–scandium–carbido/carbide EFs, VSc 2 C@ I h (7)-C 80 and VSc 2 C 2 @ I h (7)-C 80 , a reasonable mechanism—C 1 implantation (a carbon atom is implanted into carbon cage)—is proposed to interpret the evolution from VSc 2 C carbido to VSc 2 C 2 carbide cluster. Supported by theoretical calculations together with crystallographic characterization, the single electron on vanadium (V) in VSc 2 C@ I h (7)-C 80 is proved to facilitate the C 1 implantation. While the V=C double bond is identified for VSc 2 C@ I h (7)-C 80 , after C 1 implantation the distance between V and C atoms in VSc 2 C 2 @ I h (7)-C 80 falls into the range of single bond lengths as previously shown in typical V-based organometallic complexes. This work exemplifies in situ self-driven implantation of an outer carbon atom into a charged carbon cage, which is different from previous heterogeneous implantation of nonmetal atoms (Group-V or -VIII atoms) driven by high-energy ion bombardment or high-pressure offline, and the proposed C 1 implantation mechanism represents a heretofore unknown metal–carbon cluster encapsulation mechanism and can be the fundamental basis for EF family genesis.

Bulk chemicals such as ethylene glycol (EG) can be industrially synthesized from either ethylene or syngas, but the latter undergoes a bottleneck reaction and requires high hydrogen pressures. We show that fullerene (exemplified by C 60 ) can act as an electron buffer for a copper-silica catalyst (Cu/SiO 2 ). Hydrogenation of dimethyl oxalate over a C 60 -Cu/SiO 2 catalyst at ambient pressure and temperatures of 180° to 190°C had an EG yield of up to 98 ± 1%. In a kilogram-scale reaction, no deactivation of the catalyst was seen after 1000 hours. This mild route for the final step toward EG can be combined with the already-industrialized ambient reaction from syngas to the intermediate of dimethyl oxalate.

A model for photocatalytic nitrogen fixation was constructed by assembling lanthanide–transition metal (4f–3d) clusters on TiO2. Ln52Ni56 not only acts as a tool to improve charge separation but also enriches oxygen vacancies.

A novel nonclassical fullerene dihept-C70H6, captured from low-pressure combustion, is considered to be vital evidence for the further study of heptafullerenes.

Thermally induced charge transfer in a Cu3 compound (1) with a multi-center donor–acceptor architecture was observed. This work proves that dielectric measurement is a very effective means to detect charge transfer.

The precise identification of metal–metal bonds is critical to fully understanding the nature of metal–metal bonding but remains a fundamental challenge. Herein, we show the essence of Sc–Sc bonds ...

The designed synthesis of chiral luminescent molecules with excellent circularly polarized luminescence (CPL) performance and high quantum yield (QY) levels has attracted great interest but remains very challenging. Herein, we report three pairs of chiral europium-titanium-oxo clusters featuring both modest CPL characteristics and high QY levels (up to 79%), which can be regulated by switching between different ligand substituents.

Lanthanide-iron clusters usually display interesting structures and outstanding magnetic properties. However, due to the high reactivity (acidity) of the Fe

Accurately controlling the hydrolysis of metal ions can not only yield the desired structure of metal hydroxide clusters but also provide a deeper understanding of the formation process of natural hydroxide minerals. However, the capture of hydrolysis intermediates remains a significant challenge, and metal hydroxide clusters are mainly obtained by employing adventitious hydrolysis. In this study, we realized a hierarchical building block assembly from Y3+ ions to large Y12, Y34, and Y60 clusters by controlling the hydrolysis process of lanthanide ions under different pH conditions. Single-crystal structural analysis showed that the Y12 wheel, Y34 ship, and Y60 sodalite cage contain 4, 12, and 24 cubane-like [Y4(µ3-OH)4]8+ units, respectively. The structure of the Y60 cluster can be attributed to two Y34 clusters or six Y12 clusters linked by vertices. These clusters can be synthesized through the hydrolysis of Y3+ under different pH conditions, and Y60 can be prepared from the obtained Y12 or Y34 crystals by the simple addition of Y3+ ions. The capture and conversion of the intermediates of lanthanide series hydroxide clusters, Y12 or Y34, during the assembly from Y3+ ions to Y60 can facilitate an understanding of the formation process of high-nuclearity lanthanide clusters.

Hundreds of C60 derivatives stand out as electrontransporting materials(ETMs), for example, in perovskite solar cells(PSCs), due to their properties on electron extraction or defect passivation. However, it still lacks of guidelines to update C60-based ETMs with excellent photoelectric properties. In this work, crystallographic data of eight C60-based ETMs, including pristine C60 and the well-known PCBM as well as six newly synthesized fullerenes, are analyzed to establish the connections between derivatized structures and photoelectric properties for the typical carbon cluster of C60. In terms of packing centroid-centroid distance between neighboring carbon cages, the crystallographic data are useful for probing photoelectric properties, such as electrochemical properties, electron mobility and photovoltaic performances, and therefore facilitate to design novel C60-based ETMs for PSCs with high performances.

The asymmetric assembly and spontaneous resolution of chiral heterometal-organic frameworks from achiral precursors remain a great challenge. Herein, we report the formation and spontaneous resolution of three-dimensional (3D) chiral 3d–4f heterometal-organic frameworks from achiral ligands in the presence of lactic acid enantiomers as chiral inducers. In the absence of a chiral inducer, the reactants randomly generated both enantiopure crystals in equal measure. However, enantiopure lactic acid induced asymmetric resolution to achieve single chiral crystallization. DFT theoretical calculations showed that the absolute chiral resolution of the enantiomers is due to the difference in the interactions between the two enantiomeric Λ/Δ-[FeL3]3− units and the chiral inducer.

Isolating reductive silver kernel from shell is a challenging task but is quite important to understand the embryonic form during the formation of silver nanoclusters. The intercalation of suitable anionic species may be of benefit for passivating then capturing such highly active kernel. Herein, we successfully isolated a novel silver thiolate nanocluster [Ag13@Ag76S16(CyhS)42(p-NH2-PhAsO3)4]3+ (SD/Ag89a, CyhSH = cyclohexanethiol) that contains a well-isolated icosahedral Ag13 kernel passivated by four AgS47− tetrahedra and four p-NH2PhAsO32− piercing from outer Ag72 shell. Of note, this Ag13 kernel is the largest isolable subvalent silver kernel beneath the silver shell with extremely legible core-shell boundary ever before and represents a precise embryonic model formed in the reducing Ag(I) to Ag(0) followed by aggregating to large silver nanoparticles. The reductive role of DMF and the introduction of anionic passivation layer (APL) synergistically modulate the reduction kinetics, facilitating the capture of ultrasmall subvalent silver kernel. SD/Ag89a emits in near infrared (NIR) region (λem = 800 nm) at low temperature. The synthetic strategy shown in this work opens up new opportunities for precisely capturing and recognizing diverse reductive silver kernels in different systems.

A promising route toward the enantioselective recognition and separation of racemic molecules is the design of chiral metal-organic frameworks (CMOFs) with high enantioselectivity and stability. Herein, we report porous CMOFs Δ- and Λ-RuEu-MOFs constructed from the D3-symmetry helical chiral Ru(phen)3-derived tricarboxylate ligand and Eu2 units, which can be utilized as adsorbents for the enantioselective recognition and separation of 1,1'-bi-2-naphthol (BINOL) derivatives. Investigation of the circular dichroism enantiodifferentiation between the host and guest suggested that Δ- and Λ-RuEu-MOFs can be employed as chiral sensors to discriminate axial enantiomers due to their diastereomeric host-guest relationship. Density functional theory calculations reveal that chiral recognition is attributed to the distinguishing binding affinities stemming from N···H-O hydrogen bonds and π-π stacking between the host and guest. Moreover, the reticulate structure of Δ- and Λ-RuEu-MOFs can be readily recycled and reused for the successive enantioselective separation of BINOL up to 80% ee.

Based on the Venturi self-pumping effect, real-time sniffing with mass spectrometry (R-sniffing MS) is developed as a tool for direct and real-time mass spectrometric analysis of both gaseous and solid samples. It is capable of dual-mode operation in either gaseous or solid phase, with the corresponding techniques termed as R

A double-heptagon-containing C

要将荧光油墨应用于实际, 通常要求该油墨对环境友好且稳定, 并且具有良好的黏度和优异的发光性能. 本文中, 我们通过含有氨基的稀土钛氧簇Eu2Ti4-NH2 (1)与PEG (PEG = 甲氧基聚乙二醇琥珀酰亚胺碳酸酯, 2000 g mol−1)反应合成了稀土钛氧簇-高分子复合材料Eu2Ti4-NH2@PEG (2). 对2的相关表征表明, 1的结构在2之内是完整的. 1和2的发光性质表明其固态量子产率分别为50.91%和30.69%. 与化合物1相比, 2在极性溶剂中的溶解度和成膜性能大大提高. 当使用2的乙醇/乙二醇(v/v = 4/1)混合溶液用于喷墨打印的墨水时, 喷墨打印的标签显示出良好的隐蔽性和有效性.

A high-nuclearity 3d-4f cluster of [Gd30CoII6CoIII6(OH)56(NO3)12(CH3COO)30(H2O)30]·(NO3)22·(en)3·(H2O)3 (1) was synthesized through the reaction of Gd(NO3)3·6H2O, Co(NO3)2·6H2O, and sodium acetate in a mixture of ethanediamine (en), ethanol, and deionized water. The cluster core in 1 features a double-shell structure with a Co12 icosahedron encapsulating a Gd30 icosidodecahedron. A magnetic study reveals that separating Co2+ ions with Gd3+ ions can effectively reduce the magnetic interaction of 3d-4f clusters. Significantly, the magnetocaloric effect (MCE) of 1 at 2 K and 7 T is up to 44.7 J kg-1 K-1, the largest MCE reported to date in the 3d-4f metal clusters.

A 3D coordination polymer, [Gd(HCOO)(C2O4)]n was prepared. Its magnetocaloric effect (MCE) (32.7 J K-1 kg-1 at 2 K and 2 T) is significantly larger than that of commercial Gd3Ga5O12 (GGG) (14.6 J kg-1 K-1 at 2 K and 2 T), while its thermal conductivity (9.9 W m-1 K-1 at 3 K) is comparable to that of the commercial GGG (about 10 W m-1 K-1 at 3 K).

The construction of inorganic porous frameworks from discrete polyoxometalate (POM) units is a major research challenge. Herein, a three-dimensional (3D) all-inorganic porous structure {Mo154}n that consists of classic Mo154 rings connected by Mo-O-Mo covalent bonds was synthesized. Interestingly, the proton conductivity of the 3D-{Mo154}n framework is 1.1×10−2 S cm−1 at 22 °C and 100% relative humidity (RH), which is one of the highest proton conductivities reported thus far for POM-based conductive materials. Compared to the discrete {Mo154} cluster and 1D-{Mo154}n, the enhanced conductivity of 3D-{Mo154}n suggests that assembling POM-based all-inorganic porous frameworks is a promising method for designing proton-conductive materials.

Herein, a hetero(S,N)-quintuple [9]helicene (SNQ9H) molecule with an azacorannulene core was synthesized, currently representing the highest hetero-helicene reported in the field of multiple [n]helicenes. X-ray crystallography indicated that SNQ9H includes not only a propeller-shaped conformer SNQ9H-1, but also an unforeseen quasi-propeller-shaped conformer SNQ9H-2. Different conformers were observed for the first time in multiple [n≥9]helicenes, likely owing to the doping of heteroatomic sulfurs in the helical skeletons. Remarkably, the ratio of SNQ9H-1 to SNQ9H-2 can be regulated in situ by the reaction temperature. Experimental studies on the photophysical and redox properties of SNQ9H and theoretical calculations clearly demonstrated that the electronic structures of SNQ9H depend on their molecular conformations. The strategy of introducing heteroatomic sulfurs into the helical skeleton may be useful in constructing various conformers of higher multiple [n]helicenes in the future.

Herein, a nitrogen-embedded quintuple [7]helicene (

Four pairs of chiral 3D coordination polymers (CPs), [Zn2(BDC)(lac)(DMF)]·guest (2) (H2BDC = benzene dicarboxylic acid; H2lac = lactic acid; guest = 1.5DMF + i-PrOH), [Co2(BDC)(lac)(DMF)]·guest (3) (guest = DMF + 2H2O), [Fe4(BDC)3(lac)2(DMF)2](CO3)·guest (4) (guest = DMF + 2H2O), and {Zn11(BPDC)6(lac)6[NH2(CH3)2]2}·guest (H2BPDC = 3,3'-biphenyldicarboxylic acid; guest = 6DMF + 18H2O) (5), are prepared through the reactions of racemic lactic acid (rac-H2lac) with different metal ions and auxiliary ligands. Structural analyses and DFT calculations reveal that forming more and stronger coordination bonds between the auxiliary ligand and metal ions is more conducive to the spontaneous resolution of enantiomers in 3D CPs than simply increasing the entropy of the auxiliary ligand itself.

A pure inorganic uranyl phosphate-polyoxometalate of Na17{Na@[(SbW9O33)2(UO2)6(PO3OH)6]}·xH2O (abbreviated as Na@U6P6, with x ≈ 46) featuring a sandwich-type structure was prepared using Keggin-type trilacunary [α-B-SbW9O33]9- units as building blocks, which were formed in situ by SbCl3 and Na2WO4·2H2O. Crystal structural analysis showed that six UO22+ cations and six PO3OH2- anions generated a wheel-like cluster unit with a Na+ center ([Na@(UO2)6(PO3OH)6]+) that is stabilized by two [α-B-SbW9O33]9- units. Na@U6P6 displayed a solid-state photoluminescence quantum yield of 33% at 300 K. The temperature-dependent fluorescence emission spectra showed that Na@U6P6 has temperature-sensitive fluorescence in which its emission intensity decreased by 77% as the temperature increased from 200 to 300 K. These results suggest that such uranyl phosphate-polyoxometalate clusters could serve as potential temperature-sensitive molecular materials.

Great importance has been attached to magnetoelectric coupling in multiferroic thin films owing to their extremely practical use in a new generation of devices. Here, a film of [(n-C3H7)4N][FeIIIFeII(dto)3] (1; dto = C2O2S2) was fabricated using a simple stamping process. As was revealed by our experimental results, in-plane ferroelectricity over a wide temperature range from 50 to 300 K was induced by electron hopping between FeII and FeIII sites. This mechanism was further confirmed by the ferroelectric observation of the compound [(n-C3H7)4N][FeIIIZnII(dto)3] (2; dto = C2O2S2), in which FeII ions were replaced by nonmagnetic metal ZnII ions, resulting in no obvious ferroelectric polarization. However, both ferroelectricity and magnetism are related to the magnetic Fe ions, implying a strong magnetoelectric coupling in 1. Through piezoresponse force microscopy (PFM), the observation of magnetoelectric coupling was achieved by manipulating ferroelectric domains under an in-plane magnetic field. The present work not only provides new insight into the design of molecular-based electronic ferroelectric/magnetoelectric materials but also paves the way for practical applications in a new generation of electronic devices.

Cocrystallization of different metal nanoclusters facilitates the preparation of cluster-based nanomaterials with enhanced properties. Herein, two pairs of enantiomeric 3d-4f cocrystallization structures of clusters R/S-[Mn10Ln6] and R/S-[Mn6Ln2] (Ln = Dy for 1R and 1S, Y for 2R and 2S) have been reported. Compounds R/S-[Mn10Ln6][Mn6Ln2] exhibit a large optical activity and magneto-optic effect as verified by natural circular dichroism (NCD) and magnetic circular dichroism (MCD). In addition, alternating current (ac) magnetic measurements show that the chiral R/S-[Mn10Dy6][Mn6Dy2] cocrystallization structure displays slow magnetic relaxation with Ueff = 25.1 K.

Recently, Pt-based intermetallic nanoparticles (iNPs) have been intensely studied to improve the electrocatalytic activity/stability and Pt atomic utilization, but how to control the size of Pt-bas...