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Three novel donor–acceptor–acceptor configured small molecules with benzotriazole as the central A building block are synthesized as donor materials for vacuum‐deposited small‐molecule organic solar cells (SMOSCs). The effects of different lengths of the side chains attached to the benzotriazole block on the molecular structure, electrochemical behavior, and optical properties of these donors are investigated systematically. Vacuum‐deposited SMOSCs fabricated with these small molecule donors and C70 as the acceptor exhibit power conversion efficiencies (PCEs) in the range of 6.42–7.43% under air mass 1.5 global (AM 1.5 G) 100 mW cm−2 simulated solar illumination. Furthermore, the Me‐DTDCPT‐based devices deliver a promising PCE of 14.84% under 600 lux illumination by a fluorescent lamp, demonstrating its potential in indoor photovoltaic applications. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Stepwise assembly starting from a preassembled metalloligand is a promising approach to obtain otherwise unattainable silver nanoclusters, but hard to be intrinsically identified due to the lack of convincing evidence to justify such a process. Herein, hexagonal and rectangular Ag18 nanoclusters are constructed from the [Mo2O5(PTC4A)2]6− (H4PTC4A=p‐phenyl‐thiacalix[4]arene) metalloligand through stepwise assembly. The formation of the metalloligand is confirmed by electrospray ionization mass spectrometry, then assembled with silver ions to form two geometrically different Ag18 nanoclusters in different solvents. The cyclization from the metalloligand to [(Mo2O5PTC4A)6]12− can be realized without alcohols and otherwise blocked by them. The installation of this metalloligand not only provides comprehensive understanding of how the solvents regulate the silver nanocluster structures, but also brings new insights for the controllable ligand metallization and subsequent condensation. [ABSTRACT FROM AUTHOR]

The discovered giant clusters are always highly symmetric owing to the spontaneous assembly of one or two basic units. Herein we report the Gd44Co28 crown and Gd95Co60 cage, formulated as [Gd44Co28(IDA)20 (OH)72(CO3)12(OAc)28(H2O)64]⋅(ClO4)24 and [Na4Gd95 Co60(IDA)40(OH)150(CO3)40(OAc)58(H2O)164] ⋅ (ClO4)41 (H2IDA=iminodiacetic acid), respectively, by providing a library containing multiple low‐nuclearity units. The heart‐like units and crown‐like tetramer found in both compounds indicate unprecedented assembly levels, leading to an atypical geometry characteristic compared to the giant clusters directly assembled by regular units. These two clusters not only significantly increase the size of Ln−Co clusters but also exhibit the enhanced magnetic entropy change at ultra‐low temperatures. This work provided an effective way to fabricate cluster compounds with giant size and geometry complexity simultaneously. [ABSTRACT FROM AUTHOR]

Building blocks with multiple components are promising for the synthesis of complex molecular assemblies, but are rarely available. Herein, we report a modification procedure for a multi‐component building block [Ln3Ti(HSA)6(SA)4(H2O)]− ({Ln3Ti‐SA}, H2SA=salicylic acid, Ln=Eu/Gd) to form new building blocks {Ln3Tix‐MSA} (H2MSA=5‐methoxysalicylic acid, x=1, 2, 3) by constructing [Ti(MSA)3]2− units. The obtained {Ln3Tix‐MSA} can further assemble into a chiral Ln22Ti14 ring with the formulae [Eu22Ti14(MSA)48(HMSA)22(CH3COO)4(H2O)10(iPrOH)] and [Gd22Ti14(MSA)46(HMSA)26(CH3COO)4(H2O)8]. Parallel experiments without Ti4+ result in linear Ln chains. Detailed analysis shows that the [Ti(MSA)4]4− unit makes the originally variable Ln chains become available building blocks and the modified [Ti(MSA)3]2− further triggers interesting chiral‐sorting behavior. Finally, the electronic adsorption and magneto‐optic responses of these molecular rings are investigated. [ABSTRACT FROM AUTHOR]

Isomerism is common in fullerene derivatives, and the isomer‐dependent photovoltaic performance of fullerene derivatives is envisaged recently. This review article outlines recent progresses on isomerism of [6,6]‐phenyl‐C61 (or C71)‐butyric acid methyl esters (PCBMs), one of the most prevalent electronic acceptors in organic or perovskite solar cells. Recent developments about the effects of PCBMs isomers on the photovoltaic performance and device stability of organic or perovskite solar cells are summarized, including the mono‐ and bis‐adduct of PC71BM as well as the bis‐adduct of PC61BM. The open questions and future directions with involvement of isomeric PCBMs are also discussed. [ABSTRACT FROM AUTHOR]

Conical carbon, specifically multi‐walled carbon nanocones (CNCs) and single‐walled carboncones, is a new class of sp2‐hybridized carbon allotrope, in addition to fullerene, carbon nanotubes (CNTs), and graphene. Characterized by a conical and delocalized aromatic configuration, the conical carbon structure is considered the intermediate structure between planar graphene and open‐cage fullerene. CNCs can be stiffer than CNTs and exhibit intriguing physical and chemical properties owing to their unique hollow conical structure, which make these materials promising for application as field emission sources and scanning probes. The research on conical carbon structures is in its nascent stage, mainly because of the limitations in the synthesis and purification of conical carbons. This review summarizes the significant progress in the synthesis of CNCs and carboncones. Particularly, the synthetic methods, which can be divided into traditional physical‐chemical synthesis methods for multi‐walled CNCs and emerging bottom‐up organic synthesis methods for single‐walled carboncones, are comprehensively discussed. In addition, the advantages and disadvantages of the various synthetic methods as well as the possible formation and growth mechanisms of CNCs and carboncones are discussed. Finally, some outlooks on the potential solutions to the synthesis of single‐walled carboncones with uniform apex angles are presented. [ABSTRACT FROM AUTHOR]

The assembly of gigantic heterometallic metal clusters remains a great challenge for synthetic chemistry. Herein, based on the slow release strategy of lanthanide ions and in situ formation of lacunary polyoxometalates, two giant 3d‐4f polyoxometalate inorganic clusters [LaNi12W35Sb3P3O139(OH)6]23− (LaNi12) and [La10Ni48W140Sb16P12O568(OH)24(H2O)20]86− (La10Ni48) are obtained. The nanoscopic inorganic cluster La10Ni48 possesses a super tetrahedron structure, which can be viewed as assembly from four LaNi12 molecules encapsulating a central [La6(SbO3)4(H2O)20]6+ octahedron core. This giant aesthetic La10Ni48 tetrahedron containing 214 metal ions is the largest 3d‐4f cluster reported thus far in polyoxometalate system. More interestingly, the LaNi12 and La10Ni48 display high stability in solution and La10Ni48 displays excellent proton conductivity. [ABSTRACT FROM AUTHOR]

Incorporating metal clusters within the skeleton of the organic polymers through a click reaction cannot only effectively prepare cluster–polymer composites, but also effectively avoid the cluster aggregation. Herein, an azide‐containing lanthanide–titanium oxo cluster of Eu8Ti10‐N3 (Eu8Ti10‐N3=[Eu8Ti10(μ3‐O)14(H2O)4(OAc)2(tbba)30(paza)4(THF)2]⋅4 THF⋅8 H2O (1), Htbba=4‐tert‐butylbenzoic acid, Hpaza=4‐azidobenzoate, HOAc=acetic acid, THF=tetrahydrofuran) through an in situ solvothermal reaction of 4‐azidobenzoic acid and 4‐tert‐butylbenzoic acid. Reaction of 1 with PEG (PEG=methoxypoly(ethyleneglycol)alkyne, 2000 g mol−1) through CuI‐catalyzed click chemistry generates a lanthanide–polymer composite of Eu8Ti10‐N3@PEG (2). Investigation with IR, 1H NMR and ICP‐OES of 2 indicates that the structural integrity of 1 is maintained in 2. Study of the luminescent properties of 1 and 2 reveals that the quantum yield of 1 itself basically remains unchanged in 2. Significantly, the formation of 2 cannot only effectively prevent the cluster 1 from aggregation, but also greatly enhance its solubility and adhesion to the substrate. Owing to the solubility and adhesion of luminescent materials being the key to their practical application, present work is thus of great significance for the development of metal cluster–polymer composite luminescent materials. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Because of its unsaturated bonds, C60 is susceptible to polymerize into dimers. The implications of nitrogen doping on the geometrical and electronic structure of C60 dimers have been ambiguous for years. A quarter‐century after the discovery of azafullerene dimer (C59N)2, we reported its single crystallographic structure in 2019. Herein, the unambiguous crystal structure information of (C59N)2 is elucidated specifically, revealing that the inter‐cage C—C single bond length of (C59N)2 is comparable with that of an ordinary C(sp3)‐C(sp3) single bond, and that the most stable conformer of (C59N)2 is gauche‐conformer with a dihedral angle of 66°. To amend the structural deviations, geometrical structure of (C59N)2 is optimized by a B3LYP‐D3BJ function, which is proved to be more consistent with its single crystal structure than those by the commonly used B3LYP function. Moreover, the calculation method is also suitable for other representative fullerene dimers, such as (C60)2 and its divalent anion. Additionally, the dissociation of (C59N)2 at 473 K under mass spectrometric conditions suggests the inter‐cage C—C bond is relatively weaker than an ordinary C—C single bond, which can be explained by the interaction energies of inter‐cages. [ABSTRACT FROM AUTHOR]

The formation mechanism of ferrihydrite is the key to understand its treatment of pollutants in waste water and purification of surface water and groundwater. Although emerging evidence suggests that formation of the ferrihydrite occurs through the aggregation of prenucleation clusters, rather than classical atom‐by‐atom growth, its formation mechanism remains unclear. Herein, an iron–oxo anionic cluster of [Fe22(μ4‐O)8(μ3‐OH)20(μ2‐OH)18(CH3COO)16(H2O)2]4− viewed as a dimer of bivacant β‐Keggin‐Fe13 clusters was for the first time obtained by using lanthanide ions as stabilizers. Upon dissolution in a mixed solution of isopropanol and water, the lacunary β‐Keggin‐Fe13 cluster can transform into an α‐Keggin‐Fe13 cluster, distinctly demonstrating that the Keggin‐Fe13 cluster rotational isomerization can be realized through the vacant Keggin‐Fe13 cluster. [ABSTRACT FROM AUTHOR]

Magnetodielectric response mechanisms are critical for the rational design and synthesis of molecule‐based magnetodielectric materials. Herein, the magnetodielectric response was investigated in the molecule‐based material [Fe3O(CH3COO)6(py)3](py) (1). Its magnetodielectric coefficient (MD) is −2.8 % for phase transition III and −4.1 % for phase transition I. Study of the mechanism of the magnetodielectric response in 1 reveals that its magnetodielectric response at phase transition I is induced by the charge‐frustration of the trinuclear iron cluster, while that at phase transition III is attributed to the spin‐frustration of the trinuclear iron cluster, providing a new route for the design of magnetodielectric materials. [ABSTRACT FROM AUTHOR]

A large room‐temperature magnetoelectric response is crucial for the practical application of magnetoelectric materials. However, such a response has never been achieved in molecular–ionic ferroelectric‐based laminated magnetoelectric composites. Herein, the laminated magnetoelectric composite of Metglas/1 (1 = [N(CH3)4][GaBrCl3] and Metglas = an amorphous FeBSi alloy) is prepared by combining the molecular–ionic ferroelectric 1 with Metglas in the longitudinally magnetized and transversely poled (L–T) mode. The room‐temperature magnetoelectric response of the composite is up to 8.74 V Oe−1 cm−1 at the resonance frequency (≈45 kHz), representing the largest room‐temperature magnetoelectric response reported for the molecular–ionic ferroelectric‐based laminated magnetoelectric composites to date. [ABSTRACT FROM AUTHOR]

Atomically precise molecular metal‐oxo clusters provide ideal models to understand metal oxide surfaces, self‐assembly, and form‐function relationships. Devising strategies for synthesis and isolation of these molecular forms remains a challenge. Here, the synthesis of four Ln‐Fe oxo clusters that feature the ϵ‐{Fe13} Keggin cluster in their core is reported. The {Fe13} metal‐oxo cluster motif is the building block of two important iron oxyhydroxyide phases in nature and technology, ferrihydrite (as the δ‐isomer) and magnetite (the ϵ‐isomer). The reported ϵ‐{Fe13} Keggin isomer as an isolated molecule provides the opportunity to study the formation of ferrihydrite and magnetite from this building unit. The four currently reported isostructural lanthanide‐iron‐oxo clusters are fully formulated [Y12Fe33(TEOA)12(Hyp)6(μ3‐OH)20(μ4‐O)28(H2O)12](ClO4)23⋅50 H2O (1, Y12Fe33), [Gd12Fe33(TEOA)12(Hyp)6(μ3‐OH)20(μ4‐O)32(H2O)12](ClO4)15⋅50 H2O (2, Gd12Fe33) and [Ln16Fe29(TEOA)12(Hyp)6(μ3‐OH)24(μ4‐O)28(H2O)16](ClO4)16(NO3)3⋅n H2O (Ln=Y for 3, Y16Fe29, n=37 and Ln=Gd for 4, Gd16Fe29n=25; Hyp=trans‐4‐Hydroxyl‐l‐proline and TEOA=triethanolamine). The next metal layer surrounding the ϵ‐{Fe13} core within these clusters exhibits a similar arrangement as the magnetite lattice, and Fe and Ln can occupy the same positions. This provides the opportunity to construct a family of compounds and optimize magnetic exchange in these molecules through composition tuning. Small‐angle X‐ray scattering (SAXS) and high‐resolution electrospray ionization mass spectrometry (HRESI‐MS) show that these clusters are stable upon dissolution in both water and organic solvents, as a first step to performing further chemistry towards building magnetic arrays or investigating ferrihydrite and magnetite assembly from pre‐nucleation clusters. [ABSTRACT FROM AUTHOR]

All previously reported C70 isomers have positive curvature and contain 12 pentagons in addition to hexagons. Herein, we report a new C70 species with two negatively curved heptagon moieties and 14 pentagons. This unconventional heptafullerene[70] containing two symmetric heptagons, referred to as dihept‐C70, grows in the carbon arc by a theoretically supported pathway in which the carbon cluster of a previously reported C66 species undergoes successive C2 insertion via a known heptafullerene[68] intermediate with low energy barriers. As identified by X‐ray crystallography, the occurrence of heptagons facilitates a reduction in the angle of the π‐orbital axis vector in the fused pentagons to stabilize dihept‐C70. Chlorination at the intersection of a heptagon and two adjacent pentagons can greatly enlarge the HOMO–LUMO gap, which makes dihept‐C70Cl6 isolable by chromatography. The synthesis of dihept‐C70Cl6 offers precious clues with respect to the fullerene formation mechanism in the carbon‐clustering process. [ABSTRACT FROM AUTHOR]

An effective strategy is developed to synthesize high‐nuclearity Cu clusters, [Cu53(RCOO)10(C≡CtBu)20Cl2H18]+ (Cu53), which is the largest CuI/Cu0 cluster reported to date. Cu powder and Ph2SiH2 are employed as the reducing agents in the synthesis. As revealed by single‐crystal diffraction, Cu53 is arranged as a four‐concentric‐shell Cu3@Cu10Cl2@Cu20@Cu20 structure, possessing an atomic arrangement of concentric M12 icosahedral and M20 dodecahedral shells which popularly occurs in Au/Ag nanoclusters. Surprisingly, Cu53 can be dissolved in diethyl ether and spin coated to form uniform nanoclusters film on organolead halide perovskite. The cluster film can subsequently be converted into high‐quality CuI film via in situ iodination at room temperature. The as‐fabricated CuI film is an excellent hole‐transport layer for fabricating highly stable CuI‐based perovskite solar cells (PSCs) with 14.3 % of efficiency. An effective strategy is developed to synthesize high‐nuclearity Cu53 clusters that are surface‐capped by alkynyl and acetate ligands. These nanoclusters are unexpectedly soluble in ether, enabling the easy formation of high‐quality films. The cluster films are readily converted into high‐quality CuI thin films for applications as a hole transport layer in perovskite solar cells. [ABSTRACT FROM AUTHOR]

Heterometallic lanthanide–transition‐metal (4f–3d) clusters with well‐defined crystal structures integrate multiple metal centers and provide a platform for achieving synergistic catalytic effects. Herein, we present a strategy for enhanced hydrogen evolution by loading atomically precise 4f–3d clusters Ln52Ni56 on a CdS photoabsorber surface. Interestingly, some Ni2+ ions in the clusters Ln52Ni56 were exchanged by the Cd2+ to form Ln52Ni56−xCdx/CdS composites. Photocatalytic studies show that the efficient synergistic multipath charge separation and transfer from CdS to the Eu52Ni56−xCdx cluster enable high visible‐light‐driven hydrogen evolution at 25 353 μmol h−1 g−1. This work provides the strategy to design highly active photocatalytic hydrogen evolution catalysts by assembling heterometallic 4f–3d clusters on semiconductor materials. Assembling lanthanide–transition‐metal (4f–3d) clusters Ln52Ni56 (Ln=Eu, Pr, Nd and Gd) onto CdS composites achieved enhanced photocatalytic H2 production. Some Ni2+ ions in the clusters were exchanged by Cd2+ to form Ln52Ni56−xCdx/CdS composites. An Eu52Ni56−xCdx/CdS species shows the highest activity of 25 353 μmol h−1 g−1 and an apparent quantum efficiency of 42.4 %. [ABSTRACT FROM AUTHOR]

Introducing phenylphosphonic acid (H2PPA) into the Ag/tBuSH assembly system has produced a family of nanoscale‐sized, high‐atom number, silver thiolate/PPA nests (SD/Ag45 a, SD/Ag66 a, and SD/Ag73 a) with impressive core–shell features. SD/Ag45 a is a 45‐atom ellipsoid comprised of an Ag36 shell trapping an Ag9S2 three‐bladed rotor inside. SD/Ag66 a comprises an inner rod‐like Ag20 core and an outer Ag44 shell, giving a 64‐atom nest. These Ag64 nests are further extended by Ag(CN)2 linkers to form a one‐dimensional chain structure. SD/Ag73 a is a three‐shell 73‐nucleus silver nest with a central silver atom enclosed in a rhombicuboctahedron of 24 silver atoms, which is itself enclosed in the outermost shell of a rectified version of a 48‐Ag octahedral Goldberg 2,0 cage. The solution behaviors and optical absorption properties of the three nests are described in detail. Of note, SD/Ag45 a and SD/Ag73 a emit in the near‐infrared region and show different luminescent thermochromic behavior. This work demonstrates that the participation of H2PPA strongly influences the structures of silver thiolate nests, thus providing a new route to fabricate and modify them in a more rational way. A place to call home: Introducing phenylphosphonic acid into the Ag/tBuSH assembly system has led to a family of nanoscale‐sized high‐nuclearity silver thiolate/PPA nests (see figure) with impressive core–shell features, the core and shell structures consisting of Ag9S2@Ag36, Ag20@Ag44, and Ag@Ag24@Ag48 clusters. Two of the nests luminesce in the NIR region and show different luminescent thermochromic behavior. [ABSTRACT FROM AUTHOR]

Abstract: A building blocks strategy is an effective approach for constructing the large molecular systems. Herein, we demonstrate that high‐resolution electro‐spray ionization mass spectrometry (HRESI‐MS) provides an effective chance to insight the assemble process of the building blocks and guides the construction of high‐nuclearity metal clusters on the basis of the reaction of Ti(OiPr)4, Eu(acac)3, and salicylic acid. The time‐dependent HRESI‐MS indicates that not only a Eu3Ti building block can be formed, but that it can further assemble into a Eu24Ti8 compound. Temperature‐dependent HRESI‐MS reveals that increase of the reaction temperature favors the formation and crystallization of the stable Eu24Ti8 structure. Single‐crystal structural analysis demonstrates that the Eu24Ti8 has a wheel‐like structure with diameter of ca. 4.1 nm and is the highest nuclearity lanthanide‐titanium oxo cluster reported to date. [ABSTRACT FROM AUTHOR]

Above room‐temperature dielectric tunability is observed in the metal‐organic frameworks (MOFs) [NH2(CH3)2]n[FeIIIFeII(HCOO)6]n (1) and [NH2(CH3)2]n[FeIIIFeII(1−x)NiIIx(HCOO)6]n (x = 0.64–0.69) (2). The relative tunability (defined as [ϵ′(0) – ϵ′(E)]/ϵ′(0) × 100% = Δϵ′/ϵ′(0) × 100%) values for 1 are up to 35% (at 410 K) for E⊥c and 21% (at 380 K) for E||c, while these for 2 are 14% for E⊥c and 11.5% for E||c. Investigation on the mechanism of the dielectric tunability in 1 and 2 reveals that the activation energy for the electron hopping between two adjacent metal ions and the magnetic exchange interaction play a key role in the dielectric tunability of these materials. [ABSTRACT FROM AUTHOR]

Abstract: The largest known polyoxometalate (POM)‐templated silver‐alkynyl cluster, [(EuW10O36)2@Ag72(tBuC≡C)48Cl2⋅4 BF4] (SD/Ag20), was isolated under solvothermal conditions and structurally characterized. It was confirmed by single‐crystal X‐ray diffraction (SCXRD) as a {EuW10}2‐in‐{Ag72} clusters‐in‐cluster rod‐like compound. The high‐resolution electrospray ionization mass spectrometry (HR‐ESI‐MS) shows that such a double anion‐templated cluster is assembled from a crucial single anion‐templated Ag42 intermediate in the solution. The crystallization of Ag42 species (SD/Ag21), followed by SCXRD, gave an important clue about the assembly route of SD/Ag20 in solution: the Ag42 cluster eliminates six silver atoms laterally, then fuses together at the vacant face to form the final Ag72 cluster (elimination‐fusion mechanism). The characteristic emission of [EuW10O36]9− is well maintained in SD/Ag20. This work not only provides a new method for the synthesis of larger silver clusters as well as the functional integration of the silver cluster and POMs, but also gives deep insights about the high‐nuclear silver cluster assembly mechanism. [ABSTRACT FROM AUTHOR]

Abstract: Sulfonates were incorporated into six novel high‐nuclearity silver(I) thiolate clusters under the guidance of anion templates varied from S2−, SO42−, α‐[Mo5O18]6−, β‐[Mo5O18]6−, [Mo2O8]4−, to [Mo4O14(SO4)]6−. Single crystal X‐ray analysis revealed that SD/Ag1, SD/Ag3, SD/Ag5, and SD/Ag6 are discrete [S@Ag60], [α‐Mo5O18@Ag36], [Mo2O8@Ag30]2, and [Mo4O14(SO4)@Ag73] clusters, respectively, whereas SD/Ag2 and SD/Ag4 are one‐dimensional (1D) chains based on the [SO4@Ag20] and [β‐Mo5O18@Ag36] cluster subunits, respectively. Their silver skeletons are protected exteriorly by thiolates and sulfonates and interiorly supported by diverse anions as templates. Structurally, cluster SD/Ag1 is a typical core–shell structure comprised of an inner Ag12 cuboctahedron and an outer Ag48 shell. The sulfate‐templated drum‐like Ag20 cluster subunits are bridged by PhSO3− to give a 1D chain of SD/Ag2. Complex SD/Ag3 and SD/Ag4 are spindle‐like Ag36 clusters with isomeric [Mo5O18]6− inside, and the latter is further extended to a 1D chain through PhSO3− bridges. A pair of [Mo2O8]4− templated gourd‐like Ag30 clusters are dimerized in a head‐to‐head fashion to form SD/Ag5. Complex SD/Ag6 is the largest cluster in this family and doubly templated by unprecedented [Mo4O14(SO4)]6− anions. Geometrically, the silver shells of SD/Ag1–SD/Ag5 show the polyhedral features of Johnson solids, instead of the usual Platonic or Archimedean solids. Solution behaviors and luminescent properties were also investigated in detail. [ABSTRACT FROM AUTHOR]

The synthesis of Group 11 metal chalcogenide supertetrahedral clusters (SCs) still remains a great challenge mainly due to the high tendency of metal aggregation through metallophilicity and global charge balance. Demonstrated herein are the preparation, crystallographic characterization, and optical properties of two stable silver-sulfur SCs through ligand-control; one as a discrete zero-dimensional (0D) V 3, 4-type cluster and the other as a one-dimensional (1D) zigzag chain extended by alternating V 3, 2-type clusters. The notation V n, m (where n is the number of metal layers, and m is the number of vacant corners) is used to describe a new series of vacant-corner SCs, which can be derived from the regular T n clusters. The existence of vacant-corner-type SCs may be ascribed to the low valence and tri-coordinated environment of silver ions. These are the first representatives of structurally determined silver-sulfur tetrahedral clusters thus far. This work enriches the coinage-metal chalcogenide tetrahedral cluster portfolio, discovers vacant-corner SCs present in silver-sulfur hybrid tetrahedral clusters, and provides effective means for further development of Group 11 coinage-metal chalcogenide SCs. [ABSTRACT FROM AUTHOR]

The largest Ln-Fe metal cluster [Gd12Fe14(μ3-OH)12(μ4-OH)6(μ4-O)12(TEOA)6(CH3COO)16(H2O)8]⋅(CH3COO)2(CH3CN)2⋅(H2O)20 ( 1) and the core-shell monodisperse metal cluster of 1 a@SiO2 ( 1 a=[Gd12Fe14(μ3-OH)12(μ4-OH)6(μ4-O)12(TEOA)6(CH3COO)16 (H2O)8]2+) were prepared. Experimental and theoretical studies on the magnetic properties of 1 and 1 a@SiO2 reveal that encapsulation of one cluster into one silica nanosphere not only effectively decreases intermolecular magnetic interactions but also significantly increases the zero-field splitting effect of the outer layer Fe3+ ions. [ABSTRACT FROM AUTHOR]

This study demonstrates the simultaneous exfoliation and modification of graphitic carbon nitride (g-C3N4) via reductive alkylation. Our results reveal that the method is feasible and highly efficient in producing 2D g-C3N4 nanosheets which greatly overcome the drawbacks of bulk g-C3N4 photocatalyst. The reduced band gap caused by the covalent functionalization of alkyl chains on g-C3N4 lattice improves the photoresponse and the visible-light harvesting ability, indicating more charge carriers will generate under visible-light irradiation. In addition, the significantly enlarged surface area and the nanosheet structural benefits are favorable for the separation of photogenerated charge carriers. The photocatalytic activity of AGCNNs under visible-light irradiation is highly enhanced because of the synergistic effects of these favorable factors. The RhB photodegradation rate and the photocatalytic H2 evolution rate of AGCNNs are 3.9 and 1.9 times as fast as that of g-C3N4, respectively. The photocatalytic activity of AGCNNs is further improved when combined with a minority of graphene sheets which are employed as electron acceptors promoting the separation of photogenerated charge carriers. The RhB photodegradation rate and the photocatalytic H2 evolution rate of AGCNNs are further improved to 9.1 and 3.3 times as fast as that of g-C3N4, respectively. [ABSTRACT FROM AUTHOR]

Assembly of nanosized polynuclear metal clusters from simple building blocks usually involves complicated self-organization processes and thus is a long-standing challenge. Here, we demonstrate the controllable assembly, single-crystal structures and solution behaviors of four molecular assemblies based on nanosized silver alkynyl clusters, formulated as {[(CrO4)2Cl@Ag42(PhC≡C)34(CF3COO)2]⋅CF3COO} ( 1), {(NH4)[(CrO4)2Cl@Ag42(PhC≡C)34(CrO4)(H2O)2]⋅2BF4⋅CH3OH} n ( 2), [(CrO4)@Ag22(PhC≡C)16(CF3SO3)4] n ( 3), and {[(CrO4)2@Ag31(PhC≡C)22(CF3SO3)4]⋅CF3SO3⋅2CH3OH⋅H2O} n ( 4). In the presence of concomitant CrO42− and Cl− templates, we could isolate a discrete cluster 1 and a polymeric chain-like compound 2 by using different silver salts. Both 1 and 2 have a similar 42-metallic cage, which traps two CrO42− and one Cl− as anion templates. Using sole CrO42− template, 3 and 4 were simultaneously isolated in a one-pot reaction. Both of them are 1D chain structures based on single CrO42− templated Ag18 and double CrO42− templated Ag30 clusters, respectively. HR-ESI-MS was used to study the solution behaviors of 1- 4. This work has the following purposes: i) it presents the cluster engineering concept used in the assembly of polynuclear silver alkynyl clusters; ii) it exemplifies template effects from hetero and homo anions; and iii) it provides a controllable way to achieve assembly of silver alkynyl clusters. [ABSTRACT FROM AUTHOR]

Despite being widely used as electron acceptor in polymer solar cells, commercially available PC71BM (phenyl-C71-butyric acid methyl ester) usually has a 'random' composition of mixed regioisomers or stereoisomers. Here PC71BM has been isolated into three typical isomers, α-, β1- and β2-PC71BM, to establish the isomer-dependent photovoltaic performance on changing the ternary composition of α-, β1- and β2-PC71BM. Mixing the isomers in a ratio of α/β1/β2=8:1:1 resulted in the best power conversion efficiency (PCE) of 7.67 % for the polymer solar cells with PTB7:PC71BM as photoactive layer (PTB7=poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2- b:4,5- b′]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4- b]thiophenediyl]]). The three typical PC71BM isomers, even though sharing similar LUMO energy levels and light absorption, render starkly different photovoltaic performances with average-performing PCE of 1.28-7.44 % due to diverse self-aggregation of individual or mixed PC71BM isomers in the otherwise same polymer solar cells. [ABSTRACT FROM AUTHOR]

Cu(CF3COO)2 reacts with tert-butylacetylene ( tBuC≡CH) in methanol in the presence of metallic copper powder to give two air-stable clusters, [CuI15( tBuC≡C)10(CF3COO)5]⋅ tBuC≡CH ( 1) and [CuI16( tBuC≡C)12(CF3COO)4(CH3OH)2] ( 2). The assembly process involves in situ comproportionation reaction between Cu2+ and Cu0 and the formation of two different clusters is controlled by reactants concentration. The clusters consist of Cu15 and Cu16 cores co-stabilized by strong by σ- and π-bonded tert-butylethynide and CF3COO− (together with methanol molecule in 2). Their stabilities in solution were confirmed using electrospray ionization mass spectrometry in which the cluster core remains intact for 1 in chloroform and acetone, and for 2 in acetonitrile. Strong thermochromic luminescence in the near infrared (NIR) region was observed in the solid-state. Of particular interest, the emission maximum of 1 is red-shifted from 710 nm at 298 K to 793 nm at 93 K, along with a 17-fold fluorescence enhancement. In contrast, 2 exhibits red shift from 298 to 123 K followed by blue shift from 123 to 93 K. The emission wavelength was correlated with the structural parameters using variable-temperature X-ray single-crystal analyses. The rich cuprophilic interaction plays a significant role in the formation of 3LMCT ( tBuC≡C→Cux) excited state mixed with cluster-centered (3CC) characters, which can be considerably influenced by temperature, leading to thermochromic luminescence. The present work provides 1) a new synthetic protocol for the high-nuclear CuI-alkynyl clusters; 2) a comprehensive insight into the mechanism of thermochromic luminescence; 3) unusual emissive materials with the characters of NIR and thermochromic luminescence simultaneously. [ABSTRACT FROM AUTHOR]

Buckybowls are fascinating components of supramolecular assemblies owing to their unique bowl-shaped π-surfaces. Herein we present a protocol for the functionalization of a sulfur-doped buckybowl, trithiasumanene, via a brominated intermediate, from which thiolated trithiasumanenes were derived. The curved surface and electron-donating properties of thiolated trithiasumanenes promote their ready assembly with fullerenes to form concave-convex complexes. The supramolecular assembly behavior in solution was investigated by NMR analysis. The structures of supramolecular complexes were unambiguously characterized by crystallography. The crystals of the concave-convex complexes showed high thermal stability and photoconductivity. [ABSTRACT FROM AUTHOR]

Rationale Mass spectrometry (MS) has been recognized as a powerful technique to detect accurate chemical information about metal clusters. Maintaining metal clusters intact, which is a great challenge in MS analysis, was achieved in this work by choosing a suitable mass analyzer and carefully optimizing analysis parameters. Methods Electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS) and electrospray ion trap mass spectrometry (ESI-IT-MS) were applied to characterize the synthesized ligand-protected metal clusters [Au6Ag2(C)(L1)6](BF4)4 (L1 = 2-diphenylphosphanyl-4-methylpyridine) ( 1) and [Au8(L2)3(L3)2](NO3)2 (L2 = bis(2-diphenylphosphinophenyl)ether, L3 = triphenyl-phosphane) ( 2). Three kinds of buffer gas (helium, mass: 2; nitrogen, mass: 28; argon, mass: 40) and various radiofrequency (RF) amplitudes (from 70 to 330) were chosen to study the fragmentation rate during the 'collision cooling' process in the ion trap analyzer. Results In the ESI-TOF-MS analysis, metal clusters 1 and 2 were mainly observed as intact clusters, which were Au6Ag2(C)(L1)6(BF4)22+, Au6Ag2(C)(L1)6(BF4)3+, Au6Ag2(C)(L1)64+ for 1 and Au8(L2)3(L3)22+ for 2. While, in the ESI-IT-MS analysis, only fragments could be found, such as Au6Ag(C)(L1)6(BF4)2+, Au6(C)(L1)62+, Au5Ag(C)(L1)42+, Au6Ag(C)(L1)63+, Au(L1)+ for 1 and Au8(L2)3(L3)2+, Au8(L2)32+, Au6(L2)32+ for 2. It is obvious that the two kinds of mass analyzers caused different MS behaviors of metal clusters. In the ion trap (IT) mass analyzer, particularly, 'collision cooling' was contributing to further dissociation of fragile compounds, in which a higher RF amplitude and a larger mass buffer gas led to more fragmentation. Conclusion In this work, intact metal clusters were obtained in ESI-TOF-MS, instead of ESI-IT-MS, in which the 'collision cooling' process caused more cluster dissociation. It was concluded that the analyzer in ESI-TOF-MS is 'softer' than that in ESI-IT-MS for metal clusters. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Monodisperse metal clusters provide a unique platform for investigating magnetic exchange within molecular magnets. Herein, the core-shell structure of the monodisperse molecule magnet of [Gd52Ni56(IDA)48(OH)154(H2O)38]@SiO2 ( 1 a@SiO2) was prepared by encapsulating one high-nuclearity lanthanide-transition-metal compound of [Gd52Ni56(IDA)48(OH)154(H2O)38]⋅(NO3)18⋅164 H2O ( 1) (IDA=iminodiacetate) into one silica nanosphere through a facile one-pot microemulsion method. 1 a@SiO2 was characterized using transmission electron microscopy, N2 adsorption-desorption isotherms, and inductively coupled plasma-atomic emission spectrometry. Magnetic investigation of 1 and 1 a revealed J1=0.25 cm−1, J2=−0.060 cm−1, J3=−0.22 cm−1, J4=−8.63 cm−1, g=1.95, and z J=−2.0×10−3 cm−1 for 1, and J1=0.26 cm−1, J2=−0.065 cm−1, J3=−0.23 cm−1, J4=−8.40 cm−1 g=1.99, and z J=0.000 cm−1 for 1 a@SiO2. The z J=0 in 1 a@SiO2 suggests that weak antiferromagnetic coupling between the compounds is shielded by silica nanospheres. [ABSTRACT FROM AUTHOR]

A general class of C3-symmetric Ag9 clusters, [Ag9S( tBuC6H4S)6(dpph)3(CF3SO3)] ( 1), [Ag9( tBuC6H4S)6(dpph)3(CF3SO3)2] ⋅CF3SO3 ( 2), [Ag9( tBuC6H4S)6(dpph)3(NO3)2] ⋅NO3 ( 3), and [Ag9( tBuC6H4S)7(dpph)3(Mo2O7)0.5]2 ⋅2 CF3COO ( 4) (dpph=1,6-bis(diphenylphosphino)hexane), with a twisted trigonal-prism geometry was isolated by the reaction of polymeric {(HNEt3)2[Ag10( tBuC6H4S)12]} n, 1,6-bis(diphenylphosphino)hexane, and various silver salts under solvothermal conditions. The structures consist of discrete clusters constructed from a girdling Ag9 twisted trigonal prism with the top and bottom trigonal faces capped by diverse anions (i.e., S2− and CF3SO3− for compound 1, 2×CF3SO3− for compound 2, 2×NO3− for compound 3, and tBuC6H4S− and Mo2O72− for compound 4). This trigonal prism is bisected by another shrunken Ag3 trigon at its waist position. Interestingly, two inversion-related Ag9 trigonal-prismatic clusters are dimerized by the Mo2O72− ion in compound 4. The twist is amplified by the bulkier thiolate, which also introduces high steric-hindrance for the capping ligand, that is, the longer dpph ligand. Four more silver-sulfur clusters (namely, compounds 5- 8) with their nuclearity ranging from 6-10 were solely characterized by single-crystal X-ray diffraction to verify the above-described synergetic effect of mixed ligands in the construction of Ag9 twisted trigonal prisms. Surprisingly, only cluster 1 emits yellow luminescence at λ=584 nm at room temperature, which may be attributed to a charge transfer from the S 3p orbital to the Ag 5s orbital, or mixed with metal-centered (MC) d10→d9s1 transitions. Upon cooling from 300 to 80 K, the emission intensity was enhanced along with a hypsochromic shift. The good linear relationship between the maximum emission intensity and the temperature for compound 1 in the range of 180-300 K indicates that this is a promising molecular luminescent thermometer. Furthermore, cyclic voltammetric studies indicated that the diffusion- and surface-controlled redox processes were determined for compounds 1 and 3 as well as compound 4, respectively. [ABSTRACT FROM AUTHOR]

Atomically precise polyoxometalate-Ag2S core-shell nanoparticles were generated in a top-down approach under solvothermal conditions and structurally confirmed by X-ray single-crystal diffraction as an interesting core-shell structure comprising an in situ generated Mo6O228− polyoxometalate core and a mango-like Ag58S38 shell. This result demonstrates the possibility to integrate polyoxometalate and Ag2S nanoparticles into a core-shell heteronanostructure with precisely controlled atomical compositions of both core and shell. [ABSTRACT FROM AUTHOR]

Hybrid materials integrated with a variety of physical properties, such as spin crossover (SCO) and fluorescence, may show synergetic effects that find applications in many fields. Herein we demonstrate a promising post-synthetic approach to achieve such materials by grafting fluorophores (1-pyrenecarboxaldehyde and Rhodamine B) on one-dimensional SCO FeII structures. The resulting hybrid materials display expected one-step SCO behavior and fluorescent properties, in particular showing a coupling between the transition temperature of SCO and the temperature where the fluorescent intensity reverses. Consequently, synergetic effect between SCO and fluorescence is incorporated into materials despite different fluorophores. This study provides an effective strategy for the design and development of novel magnetic and optical materials. [ABSTRACT FROM AUTHOR]

Two molecular rotors were synthesized (see picture). An investigation of the rotator rotation based on the imaginary parts of the complex dielectric constant (ε′′) for each molecular rotor at various frequencies and temperatures revealed that the rotation of the mono‐component molecular rotor could be modulated through hydrogen‐bonding interactions between the rotator and the stator. [ABSTRACT FROM AUTHOR]

Four compounds with general formula [Fe(4-bphz)2(NCS)2] ·X [4-bphz = 1,2-bis(pyridin-4-ylmethylene)hydrazine; X = 2H2O ·2CH3CN ( 1·CH3CN), 4CH3COCH3 ( 2·CH3COCH3), 2.5C10H8 ( 3·C10H8), 2C6H5NO2 ( 4·C6H5NO2)] were synthesized and characterized. These compounds contain 2D gridlike networks that are diversely stacked or self-interpenetrated depending on the inclusive guest molecules. Magnetic studies showed that 1·CH3CN undergoes a two-step and almost complete spin transition and 2·CH3COCH3 showed an incomplete transition, whereas 3·C10H8 and 4·C6H5NO2 are paramagnetic in the whole temperature range. Correlations between structures and magnetic properties revealed that the size and shape of the guest molecules exerted great influence on the conformation of the ligand and the 3D structures of the complexes and, hence, spin-crossover behaviors. [ABSTRACT FROM AUTHOR]

A series of FeII complexes based on [Fe(tpa)]2+ building units and [N(CN)2]- bridging ligands with different anions for charge balance has been prepared and characterized. They have a general formula [Fe(tpa){N(CN)2}] x ·Y ·Z, where x = 4 ( 14+), Y = 4ClO4-, and Z = 2H2O for 1·(ClO4)4(H2O)2; x = n ( 2 n+), Z = 0, and Y = nClO4-, nPF6-, nAsF6-, and nBPh4- for 2·(ClO4) n, 2·(PF6) n, 2·(AsF6) n, and 2·(BPh4) n, respectively; x = 2 ( 32+), Z = 0, and Y = 2BPh4- for 3·(BPh4)2; x = 4 ( 44+), Y = 3SbF6- + [N(CN)2]-, and Z = [Fe(tpa){N(CN)2}2] ( 5) + 4H2O for ( 4+ 5). Single-crystal X-ray diffraction studies reveal that these complexes show various structures that are affected by different counteranions, i.e., square 1·(ClO4)4(H2O)2, zigzag polymers [ 2·(ClO4) n, 2·(PF6) n, 2·(AsF6) n, and 2·(BPh4) n], dimeric 3·(BPh4)2, and [4+1]-cocrystallized ( 4+ 5). Magnetic studies show that the square complex 1·(ClO4)4(H2O)2 undergoes a two-step complete spin crossover, whereas the dimer 3·(BPh4)2 is high-spin in the whole temperature range, and all zigzag polymer 2·anions show spin-crossover (SCO) behavior, the transition temperature ( T1/2) of which increases with increasing anion size. Interestingly, complex ( 4+ 5) displays a gradual two-step spin crossover, which is different from that of 1·(ClO4)4(H2O)2 and originates from the cocrystallized spin-crossover tetranuclear and monomeric species. Detailed studies on the crystal structures and magnetic properties have unveiled a remarkable anion-dependent formation of different structures and SCO behavior of these complexes. [ABSTRACT FROM AUTHOR]