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The reaction of the carbazole ligand supported Ga(I) compound LGa(THF) (3) and 1-azido-4-(tert-butyl)benzene (ArN3) afforded the first stable tetrazagallole LGaN4Ar2 (4) bearing a three-coordinate Ga atom. Reduction of 4 with elemental potassium resulted in the radical dimer {[K(18-c-6)]+[4]˙-}2, featuring a strong antiferromagnetic interaction between the spin centers.

Although the water gas shift (WGS) reaction has sparked intensive attention for the production of high-purity hydrogen, the design of cost-efficient catalysts with noble metal-like performance still remains a great challenge. Here, we successfully overcome this obstacle by using Se-incorporated MoS2 with a 1T phase. Combining the optimized electronic structure, additional active sites from edge sites, and a sulfur vacancy based on the 1T phase, as well as the high surface ratio from the highly open structure, the optimal MoS1.75Se0.25 exhibits superior activity and stability compared to the conventional 2H-phase MoS2, with poor activity, large sulfur loss, and rapid inactivation. The hydrogen production of MoS1.75Se0.25 is 942 μmol, which is 1.9 times higher than MoS2 (504 μmol) and 2.8 times higher than MoSe2 (337 μmol). Furthermore, due to the lattice stabilization via Se-incorporation, MoS1.75Se0.25 exhibited excellent long-term stability without obvious change in more than 10 reaction rounds. Our resu...

Ferrous ion (FeII)-induced activation of persulfate (S2O82−), reference to the generation of sulfate radical (SO4 −), has attracted considerable attention in water treatment for refractory organic contaminants removal. However, two major challenges, i.e., the required acidic pH condition and the extremely slow FeIII/FeII redox cycle, limit the application of FeII/S2O82− process. Herein, the present work addresses S2O82− activation in aqueous solutions at neutral pH by a ferric-nitrilotriacetic (FeIII-NTA) complex under low pressure UVA irradiation. The results showed that UVA irradiation-induced FeIII-NTA reduction could effectively enhance FeIII/FeII redox cycle for the S2O82− activation under neutral pH condition. Electron spin resonance spectroscopy (ESR) and radicals quenching tests indicated that the major reactive species included SO4 − and hydroxy radicals (HO ) in UVA/FeIII-NTA/S2O82− process, which contributed more than 80% degradation of a model compound carbamazepine (CBZ). In addition, comprehensive investigations were conducted on the important parameters including NTA:FeIII molar ratio, initial pH, FeIII-NTA and S2O82− dosages and their impacts on CBZ degradation kinetics. The critical NTA:FeIII molar ratio was determined at 1:1, above this ratio the excess NTA would act as a scavenger of SO4 −/HO thereby inhibiting the degradation of CBZ. The secondary reaction rate constant of NTA with SO4 − was determined at 5.89 × 107 M−1 s−1. Moreover, the degradation of CBZ by UVA/FeIII-NTA/S2O82− process in real water matrix (lake water, groundwater and tap water) with environmentally relevant concentration were conducted, and the efficacies were compared with UVA/FeIII-NTA/H2O2 (i.e., photo-Fenton-like) process. The degradation mechanism and pathway of CBZ were proposed on the basis of the identified intermediates by using LC-QTOF-MS technique.

Aerosol-assisted methods possess a strong capability for synthesis of titania (TiO2) microspheres. For dynamic separation applications, rough TiO2 microspheres with uniform large micron sizes, high external-surface-area-to-volume ratios, high surface areas, uniform mesopores and abundant hydroxyl groups are desirable. Herein, we demonstrate the combination of evaporation induced self-assembly (EISA) with a microfluidic-jet spray drying process for scalable synthesis of novel mesoporous TiO2 materials with the above-mentioned properties for Cr(VI) removal under both static and dynamic conditions. The TiO2 materials are spherical with uniform large micron sizes (∼45 μm). They possess wrinkled surfaces and thus have high particle external-surface-area-to-volume ratios. They show high surface areas (22–138 m2 g−1), large pore volumes (0.15–0.27 cm3 g−1) and uniform mesopores (5.2–20.7 nm). They carry abundant surface Ti–OH groups due to the presence of oxygen vacancies and the Ti3+ valence state. Several experimental parameters, such as drying and calcination temperatures, are varied, leading to TiO2 samples with tunable surface areas and mesopore sizes. They can be adopted as batch sorbents for removal of Cr(VI) in water with fast adsorption rates, large capacities and pH-dependent adsorption behavior. Part of the adsorbed Cr(VI) can be reduced to Cr(III) in acidic solutions. The influences of adsorbent properties on adsorption performance are elucidated. Moreover, their uniform large micron sizes make them excellent fillers for efficient separation of Cr(VI) in dynamic flows with similar performance to that under static conditions, as well as easy regeneration and high cycling stability. Their adsorption performance under flowing conditions is much better than those of commercial TiO2 nanoparticles and mesoporous TiO2 materials prepared by a conventional EISA method, which make them very attractive for practical dynamic separation applications.

Pyridine CTF (CTF-Py) grafted on the surface of NH2-functionalized TiO2 (NH2-TiO2) nanoparticles gave composite TiO2@CTF-Py covalently linking the inorganic semiconductor to the nitrogen-rich porous, conjugated and coordinating organic functionality. Co2+-modified TiO2@CTF-Py was an efficient photocatalyst for the reduction of CO2 to CO with high selectivity using water as the electron donor and without exogenous photosensitizers or a sacrificial agent. The covalent connection between the semiconductors and NNN coordination group were important for this photocatalytic activity and selectivity.

Although the water gas shift (WGS) reaction has sparked intensive attention for the production of high-purity hydrogen, the design of cost-efficient catalysts with noble metal-like performance still remains a great challenge. Here, we successfully overcome this obstacle by using Se-incorporated MoS

Although a lot of thiogermanates with transition metal amine complexes have been successfully synthesized, thiogermanates with vanadium complexes are largely unexplored. Two such new thiogermanates, {[V(en)2]2O}Ge2S6 (1) (en = ethylenediamine) and [VO(dap)2]2Ge2S6·dap (2) (dap = 1,2-diaminopropane), are now synthesized and characterized crystallographically. Compound 2 shows a supramolecular structure with hexagonal nano tubes assembled through N–H⋯S hydrogen bonds. The nano-tubes are further closely packed with strong N–H⋯O hydrogen bond interactions to form a honeycomb-like structure. Although the sulfur (S)–amine systems are common in the synthesis of chalcogenidometalates, the results of this work give a new demonstration of amine induced variation in molecular structures and the valance state of vanadium, though the two amines are only different by a branched methyl group.

Remarkable progresses regarding pure inorganic frameworks and metal-organic frameworks (MOF) have been made. However, pure inorganic frameworks with MOF-like grid structures are rarely reported due to the weakness of inorganic moiety as a long linear linker. We report herein a fascinating inorganic framework assembled by a [Ge4S10]4- cluster node and a linear [-Cu-MS4-Cu-] (M = Mo (1) and W (2)) inorganic pillar. Their network shows MOF-like orthogonal structure with two interpenetrated two-dimensional (2D) plus 2D to 3D framework and a 1D nano tunnel. Electrodes with crystalline sample of 1 and 2, inorganic sulfide framework, were prepared, and their quasi-capacitance behaviors were investigated. Electrochemical performances were evaluated by cyclic voltammetry and galvanostatic charge-discharge techniques in CsOH, KOH, NaOH, and LiOH electrolytes. The results revealed that the crystal materials exhibit moderate specific capacitance values that are comparable to those of porous sulfide materials.

Three tantalum oxyfluoride compounds, [Fe(phen)3][Ta2OF10] (1), [Fe(phen)3][Ta2OF10]·2H2O (2), and [Ru(phen)3]2[Ta2OF10][TaF6]2 (3), were synthesized by a two-step hydrothermal method and their crystal structures were characterized by single-crystal X-ray diffraction. The unique characters of these compounds are the [M(phen)3]2+ cations. C–H···F interactions exist between cations and anions and O–H···F hydrogen bonds exist between the water molecules and anions. Photocurrent measurements reveal that compound 3 is the photoelectric responsive with the moderate current intensity.

A lot of ternary In-Sb-Q (Q = S, Se) chalcogenido-metalates with amines or complex cations have been recently reported for their diverse structures, however, such a type of In-Sn-Q chalcogenido-metalate has been rarely announced. Herein, we report a series of 2-D In-Sn-Q compounds prepared using a metal-phenanthroline cationic template, [M(Phen)3](In2Sn2Q8)·(amine)·nH2O (M = Ni(II), Fe(II) or Co(II); amine = cyclohexylamine (Cha) or 1,6-diaminohexane (Dah); Q = S or Se). Their anions are isostructural and a 2-D porous network with large 16-tetrahedron-rings. The 2-D network joint of In-Sn-Q is a (In/Sn)3Q3 six-membered ring, which is different from the Sn3Q4 pseudosemicube of most 2-D Sn-Q binary compounds. The materials exhibit photocurrent response properties measured using a photo-electrochemical cell. The result shows that (1) the selenides exhibit more intense photocurrents than the sulfides and (2) the current intensity is related to the metal-phenanthroline cations.

Crystal structures and properties of two new ion pair charge-transfer (IPCT) compounds, [DMBPE]2Ge4S10·8H2O (1) and [DMBPE]2Ge4S10·5H2O (2), (DMBPE = N,N′-dimethyl-1,2-bis(4-pyridinium)-ethylene) are characterized. The IPCT property was confirmed by their charge-transfer absorption bands. Fluorescence emission for 1 in water was observed, that is affected by the cation–anion interaction. The photocurrent measurement showed that compounds 1 and 2 are also photoelectric responsive materials.

Two wheel-shaped In18Te30 clusters with M-phen complex cations, [M(phen)3]2[In18Te30(dapn)6]·2Hdapn·dapn (M = Fe(II), and Ni(II), dapn = 1.3-diaminepropane), were prepared. The In18Te30 anion shows a double-layered ring structure that assembled by six In2Te6 subunits and six InTe3N tetrahedra. The size of the wheel-shaped clusters is about 1.6 nm. In the crystals clockwise and anticlockwise complex cations [M(phen)3]2+ are coupled through π⋯π interaction forming a dimer structure and the dimers are interacted with the clusters via C⋯Te (about 3.60 A) short contacts. The sizes of the dimer cation and the anion are well compensated in crystal packing. Although there is wider range absorption of the In–Te anion, the MLCT transition of the Fe-phen cation still contributes to the low energy absorption.

Our efforts have focused on the synthesis of novel chalcogenidometalates, in which M-phen/bpy complexes are embedded (M = transition metals, phen = 1, 10-phenanthroline, bpy = 2, 2′-bipyridine), because the MII-phen/bpy cations have offered extensive applications in light harvesting and energy conversion. We report herein discrete supertetrahedral Fe4In16S35 clusters (T4) co-crystallized with [Fe(bpy)3]2+ cations, namely [Fe(bpy)3]3[Fe4H2In16S35]·4Htean·2Hbpy·5H2O. The spectroscopic properties and thermal stability of the compound are discussed. It is the first example of a non-corner-capped discrete M4In16S35 T4 cluster. A notable feature of the compound is the soluble discrete nanoscaled thioindiate cluster. The related 1D InS T3 chain [Fe(bpy)3]2[H2In10S19]·2Htean·8H2O is also presented herein in order to understand the effect of the reaction conditions on the formation of the Tn structures.

We have reported main group metal chalcogenido clusters of cubic [InQ(phen)Cl] 4 (Q = S ( 1 ) and Se ( 2 ); phen = 1,10-phenanthroline). Herein two new cubic clusters with ligand of 2,2′-bipyridine (bpy) have been synthesized by solvothermal technique, [InSe(bpy)Cl] 4 ( 3 ) and [InS(bpy)Cl] 4 ·H 2 O ( 4 ). The molecular structures and electronic states of compounds 3 and 4 are presented by comparing with those of 1 and 2 . Though the clusters of 1 – 4 are similar, their packing structures show diverse modes. Spectroscopic study and theoretical calculation indicate that introducing phen/bpy to chalcogenido clusters can decrease the energy gap of frontier orbitals from HOMO to LUMO due to the cluster to ligand charge-transfer (CLCT). Increasing the conjugated system of the organic ligand or using the heavier chalcogenido element might improve the photophysical absorption of the materials.

Reaction of Au(PPh3)Cl with MET-TTF in the presence of air resulted in a new charge-transfer salt [AuCl2(DDDT)](MET-TTF) (1, DDDT = 5,6-dihydro-1,4-dithiin-2,3-dithiolate, MET-TTF = bis(methylthio)ethylenedithiotetrathiafulvalene). During the air-induced reaction, the Au(I) is oxidized to Au(III), while two C-S bonds in MET-TTF were cleaved simultaneously. In the crystal the radical cations in 1 are assembled into a 1D structure by intermolecular S・ ・ ・ S, S・ ・ ・C, and C・ ・ ・C contacts.

The synthesis of the transition metal coordination polymers containing a tetrathiafulvalene (TTF) moiety substituted with a tetracarboxylate group of the formulas [Mn(L)(0.5)(phen)(H(2)O)(2)](n).nH(2)O (1), [Mn(L)(0.5)(bpy)](n).nH(2)O (2), [Mn(L)(0.5)(bpy)(CH(3)OH)](n).2nH(2)O (3), and [Cu(L)(0.5)(bpy)(DMF)](n).n(DMF) (4) (L(4-) = TTF-tetracarboxylate; phen = 1,10-phenanthroline; bpy = 2,2'-bipyridine) is reported. Complex 1 is a two-dimensional (2-D) coordination polymer constructed of infinite carboxylate bridged Mn(II) chains and TTF moiety linkages. Complex 2 possesses a 3-D polymeric structure formed by infinite -Mn-(O-C-O)(2)-Mn- bridged one-dimensional (1-D) chains, which are further coordinated by TTF-tetracarboxylate ligands of two different orientations. Both complexes 3 and 4 show 1-D extended chain structures but are constituted by different dinuclear metal(II) units with a -Mn-(O-C-O)(2)-Mn- bridge in 3 and a -Cu-(O)(2)-Cu- bridge in 4. Electrochemical study of the solid-state compounds attests to the redox activity of the coordination system. Magnetic investigations reveal the existence of antiferromagnetic interactions between magnetic centers in complexes 3 and 4, while in 1, the paramagnetic metallic centers are isolated, in agreement with the solid-state structure.

Four coordination compounds of calcium and magnesium with tetrathiafulvalene (TTF) bicarboxylate ligand have been synthesized and characterized by single-crystal analysis. As well-studied bicarboxylate complexes, the carboxylate groups in this ligand coordinate to alkaline earth metal ions in multidentate modes forming compounds 1−4. Calcium compounds [CaL(DMF)2] (1) and [Ca2L2(H2O)2(EtOH)]·MeOH (2) take a seven-coordinated sphere with a pentagonal bipyramid geometry, while magnesium compounds [Mg2L2(H2O)7]·EtOH·4H2O (3) and [Na2(DMF)2(H2O)9][MgL2(DMF)2] (4) are six-coordinated with an elongated octahedral geometry. The effect of metal ion radii on the coordination structure is clearly exhibited. The molecules of these alkaline-earth metal complexes are assembled to a sandwiched structure with hydrophobic layers of a sulfur-rich TTF matrix and hydrophilic layer of the metal carboxylate. Equilibriums of the metal coordination, acid dissociation, and ligand oxidation have been studied in the solution system...

Two new thiostannates [M(tepa)]2(μ-Sn2S6) (tepa = tetraethylenepentamine, M = Fe2+ 1 and Co2+ 2) were prepared by solvothermal method. Compounds 1 and 2 are isostructural. Both the compounds crystallize in the tetragonal system, space group I41/a (no. 88) with the crystal parameters of 1: a = 25.683(2) A, b = 25.683(2) A, c = 9.9860(9) A, V = 6,586.7(11) A3, Z = 8, and 2: a = 25.742(3) A, b = 25.742(3) A, c = 9.8977(12) A, V = 6,558.5(14) A3, Z = 8. The Sn2S6 4− anion acts as a bidentate bridging ligand connecting two transition metal complex cations by trans terminal S atoms to form neutral centrosymmetric [M(tepa)]2(μ-Sn2S6) moieties. The Sn2S6 4− anion acts as a bidentate bridging ligand connecting two transition metal complex cations by trans terminal S atoms to form neutral centrosymmetric [M(tepa)]2(μ-Sn2S6) moieties.

Two high porous thioindates with 1,6-diaminohexane (DAH), DAH-InS-1 and DAH-InS-2, were prepared by solvothermal reaction. Though the same T3 supertetrahedral frameworks were reported, the cations are different. DAH is a non-cyclic diamine and also an economical reagent for synthesis. Because of the structural difference of the structural directing agents, the dimensions of crystal cells of DAH-InS-1 and DAH-InS-2 are elongated and the total volumes for the cation and solvent are 74.6 and 72.1 % (Platon) larger relative to those reported previously. The two compounds were obtained in one reaction system by controlling the reaction time. Their structures are briefly discussed and the correlativity of crystal shape with the parameters of microstructure is discussed.

Solvothermal growth of cuprous selenide films on copper substrate has been succeeded by treating copper foil in the mixture of selenium powder and amines or hydrazine. The films were characterized by methods of XRD, SEM, TEM and optical spectra (Cu2Se, JCPDS 47-1448). Films with hexagonal microcrystals can be obtained in hydrazine/water reaction system. When CTAB (CTAB = cetyltrimethylammonium bromide) is added to the system, the film is composed of thin leaf-like microcrystals. When ethylenediamine (en) is used as solvent, the leaf-like microcrystals are crimped.

Inorganic–organic hybrid chalcogenidometalate materials have attracted considerable interest, because they are a new type of materials with unique topologic structures. The syntheses of these materials are typically carried out under hydro(solvo)thermal conditions at relatively low temperatures. Organic amines have been demonstrated to be successful and versatile molecules to be used in template-directed synthesis of numerous chalcogenide-based open-framework materials. Some comprehensive reviews have summarized the preparation and structures of the chalcogenidometalates with non-chelating amines. Extended and embedded researches on the chelating amines containing a different number of N -donor atoms have recently attracted more interest in synthetic chemistry. A series of unique inorganic–organic hybrid chalcogenidometalate materials are successfully isolated lately. This review focuses on the recent developments in solvothermal synthesis of main group chalcogenidometalates in the presence of organic chelating amines or polyamines as reaction medium. In contrast to the non-chelating amines, the roles of the chelating amines in the syntheses and the effects of the chelating amines on the crystal structures are discussed. A comprehensive outline of the chalcogenidometalate compounds with metal complex cations is also presented.

Two new indium selenides [In(en)2Se]2·2I (1) and [In(teta)Se]2·2I (2) (en = ethylenediamine, teta = triethylenetetramine) were obtained under mild solvothermal conditions and structurally characterized. Compounds 1 and 2 consist of unusual organic hybrid indium selenide cations and I− anions. These ions are assembled to two different supramolecular structures by N-H···I and N-H···Se H-bonds, namely extended 3-D network structure for 1 and extended sheet structure for 2. The optical band gaps of 2.92 eV for 1 and 3.15 eV for 2 were derived from optical absorption spectra. The thermal stability of 1 and 2 was investigated by thermogravimetric measurements.

Four new gallium chalcogenides [H2dap]4Ga4Se10 (1), [Mn(dap)3]0.5GaSe2 (2), {[Ni(tepa)]2SO4}[Ni(tepa)(Ga4S6(SH)4)] (3) and [Mn(atep)]Ga2S4 (4) (dap = 1,2-diaminopropane, tepa = tetraethylenepentamine, atep = 4-(2-aminoethyl)triethylenetetramine) have been synthesized by solvothermal methods and structurally characterized. The effects of the strong chelating amines on the topology of gallium chalcogenidometalates have been enumerated. First, in the absence of transition metal ions, the chelating amine can offer more N−H groups than the monoamines to form hydrogen bonds; therefore, compound 1 takes a 2-D polymeric structure constructed by supertetrahedral clusters ([Ga4Se10]8−, T2). Second, when transition metals are incorporated into the chelating amine system, larger [M(dap)3]2+complex cations are formed, which force the anions of compound 2 to adopt a 1-D structure ([GaSe2]− chain). Third, when an appropriate chelating amine (e.g., tepa) is selected, unsaturated transition metal complex cations can be ob...

Four complexes with 4′,5′-diaza-9′-[4,5-bis(methylthio)-1,3-dithiol-2-ylidene]fluorene (L1) or 4′,5′-diaza-9′-[4,5-bis(ethylthio)-1,3-dithiol-2-ylidene]fluorene (L2) were synthesized. The complexes [Co(L1)2Cl2]·2CH3OH (1), [Cu(L2)2Cl2]·CH3OH·0.5CH2Cl2 (3), and [Cu(L2)2Br2]·CH3OH (4) adopt a trans configuration and the compound [Cd(L1)2(NO3)2] (2) is a cis structure. Short S···S, C···C, and C···S contacts were found to be important in the molecular packing. Both the solution and solid-state electronic spectra show a redshift in the intramolecular CT bands when forming metal complexes. This intramolecular charge transition in the solid state is enhanced relative to that in solution. Their third-order nonlinear optical properties of compounds 1–4 were studied, and the results reveal that these complexes exhibit negative γ values (about 10–30) and are self-defocusing samples. These γ values are comparable to those of the known cluster compounds. The trans coordination of the two ligands to the metal center would be beneficial to the NLO properties. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Two new thioantimonates [M(dap)3]Sb4S7 (M = Ni2+ (1) and Co2+ (2)) were synthesized under solvothermal conditions by the reaction of NiS (or Co metal), Sb and S in an aqueous solution of 1,2-diaminopropane (dap). Compounds 1 and 2 are isostructural. The polymeric [Sb4S72−]n anion is composed of two SbS3 trigonal pyramids and two SbS4 units. The SbS3 and SbS4 units are interconnected by corners and edges to build a 2-D puckered layer with Sb4S4 and Sb16S16 heterorings. The apertures of the large Sb16S16 hetero-rings are filled by two [M(dap)3]2+ complex cations which serve as template ions. The band gaps of 2.44 eV for 1 and 2.43 eV for 2 have been estimated from optical absorption spectra.

A silver coordination compound [Ag(I)(DMT–TTF-py)2CH3CN] ClO4 · CH2Cl2 has been synthesized by reaction of DMT–TTF-py with AgClO4. Structure analysis shows that the cations self-assemble to dimeric units through Ag ··· Ag interactions. Each silver(I) has a T-shaped AgN3 coordination geometry. In the dimeric units, there are short C ··· S and C ··· C contacts between the two DMT–TTF-py molecules. The dimeric units are further assembled to a zigzag packing structure. The cyclic voltametric behavior of the ligand shows two-step reversible redox waves, which are shifted to lower values due to coordination to silver.

A series of one-dimensional (1-D) telluridoindate compounds built from InTe4 tetrahedra sharing opposite edges were synthesized, and the structures of the {[InTe2-]}∞ chains were classified as three types. Compound [Zn(taa)(μ-tren)0.5][InTe2]Cl (Ia) has a common structure feature of a 1-D straight chain (type I). Compounds [M(en)3]In2Te4·en (M = Ni (IIa) and Co (IIb)) have a sinusoidal 1-D structure with [In4Te8] 4- periodic units (type II), while compounds [M(en)3]2(en)0.5In4Te8 (M = Mn (IIIa), Fe (IIIb), and Zn (IIIc)) show another type of sinusoidal anionic chain (type III). The repeating unit of type III consists of eight edge-sharing tetrahedra for a complete sinusoidal period, [In8Te168-]n. Although numerous 1-D polymeric anion chains built from MQ4 tetrahedra with the formula of {[MQ2]n-}∞ exist, these chains are usually straight. The compounds of types II and III are rare examples of 1-D chains within main group chalcogenometalates.

Two new selenidostannates [M(tepa)]2(μ2-Sn2Se6) (tepa = tetraethylenepentamine, M = Fe2+ 1 and Co2+ 2) were prepared by solvothermal reaction at 157 °C. Compounds 1 and 2 are isostructural. The M2+ ion has a distorted octahedral geometry comprised of five N atoms from tepa ligands and one terminal Se atom of the Sn 2 Se 6 4 - anion. As a bridging ligand, Sn 2 Se 6 4 - anion connects two transition metal complex cations by trans terminal Se atoms to form neutral centrosymmetric [M(tepa)]2(μ2-Sn2Se6) moieties. Their thermal and optical properties were studied.

Three new radical salts, [DMT-TTF-(CONHMe)2]2CuBr4 (2), DMT-TTF-(CONHMe)2·ClO4 (3), and DMT-TTF-(CONHMe)2·Br (4), have been obtained by reacting DMT-TTF-(CONHMe)2 (1) with CuBr2 and Cu(ClO4)2 (DMT-TTF = dimethylthio-tetrathiafulvalene). The [DMT-TTF-(CONHMe)2]•+ cations of the three compounds are self-assembled to cation couples with short S···S and C···C stackings. Radical coupling was found within these TTF dimers, the intensity of which is related to the stacking distance between the coupled TTF molecules. When the S···S stacking is of a comparative intensity, the C···C stacking distance will play an important role in the antiferromagnetical coupling of the radicals. The intensity of the radical signals in electron spin resonance (ESR) was found to be in the order 2 < 3 < 4, which is related to the π···π stacking distance of the central CC bonds of the TTF moieties. The stronger the C···C interactions are, the weaker the radical signal becomes in the ESR spectra.

The synthesis and crystal structure of a new tetrathiafulvalene (TTF) derivative with an acetylacetone substituent are reported (3-(dimethylthio-TTF-thio)-2,4-pentane-dione, DMT-TTF-acac (1)). Compound 1 consists of a TTF plane and an acac plane, which are bridged by a sulfur atom. The bond distances and angles of 1 clearly indicate that the acetylacetone group adopts a keto–enol structure with an O–H⋯O intramolecular hydrogen bond. As usually observed for TTF derivatives, compound 1 exhibits two-step reversible redox waves on CV measurement, which are sensible to the metal ions being added. The stronger the metal coordination is, the larger the potential shift would be. Two complexes of 1, [M(DMT-TTF-acac)2] M = Mn(II) and Cu(II), have been prepared and they are very stable even in the state in which the ligands are oxidized. The iodine-doped compound of Mn(II) is a new organic–inorganic system consisting of paramagnetic metal ions and organic radicals.

A new dinuclear metal complex including tetrathiafulvalene (TTF) radicals as ligands has been prepared and characterized, [{DMT-TTF(CONH2)2}2Cu2Cl6] (1), DMT-TTF(CONH2)2 = o-bis(amido)-appended dimethylthio-tetrathiafulvalene. The compound is an uncommon example in which TTF radicals directly coordinate to the copper(II) halide by the amido group. Crystal structure analysis shows that it is a unique coordination bond/H-bond/S···S stacking cooperative system with two radicals and two paramagnetic transition metal ions, TTF+·–CuII–CuII–TTF+·. In the structure of 1, the DMT-TTF units form dimers with very strong S···S interactions. The CuII–O(amide) distance of the coordination bond is 2.271(2) A and the S···S stacking distances between the radicals are in the range 3.345–3.489 A. The metal–metal ions are mildly antiferromagnetically coupled (2J1 =–58.4 cm–1), while the radical pairs are strongly antiferromagnetically coupled (2J2 > –1000 cm–1).(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

The preparation and physical characterization are reported for a family of novel Mn12 single-molecule magnets having diphenylphosphate (labeled dppH) bridges, [Mn12O12(O2CR)16 − x(dpp)x(H2O)y] (R = CH3: x = 4, y = 0 (1); x = 8, y = 2 (2), R = Ph: x = 4, y = 4 (5); x = 8, y = 4 (6), and R = Et: x = 4, y = 4 (9)) and their tetraphenylphosphate salts [Ph4P][Mn12O12(O2CR)16 − x(dpp)x(H2O)4] (R = CH3: x = 4 (3); x = 8 (4) and R = Ph: x = 4 (7); x = 8 (8)). The crystal structures of 1 and 5 were characterized by X-ray. The X-ray structure analysis of 1 reveals that there are four five-coordinate MnIII ions with Mn⋯H approaches and without coordinating water molecules. The 1H NMR measurements show H2O can coordinate to a vacant site of 1 in CD2Cl2 solution. Ac magnetic susceptibility measurements indicate that nine complexes are single-molecule magnets. The increase of the number of dpp− ligands resulted in a decrease of the Ueff values of neutral Mn12 SMMs estimated from ac measurements. Complexes 1 and 5 show a quantum tunneling behavior, whose ground states were tentatively assigned to S = 10 with g = 1.78, and D = −0.60 K; S = 10 with g = 1.92, and D = −0.63 K, respectively.

The preparation and physical characterization are reported for three Mn12 single-molecule magnets (SMMs) having naphthalenecarboxylate bridges, [Mn12O12(2-nc)16(H2O)4] (1, 2-ncH = 2-naphthalenecarb...

Complex [Mn12O12(OAc)16(MeOH)4] having MeOH-coordination was synthesized and characterized, whose magnetic behaviors indicate it is a single-molecule magnet with the largest Ueff/kB of 76.2 K.

The metal complex, [Hg2I4(PEDT)]∞ (1), PEDT=4,5-(phenyl-ethylenedithio)-1,3-dithiole-2-thione, has been synthesized and characterized by single crystal X-ray diffraction. It is found to be an unusual organic–inorganic hybrid structure. The inorganic layer is composed of chains of Hg with bridging I, in one case doubly bridged and in the other singly, interconnected by further bridging I to complete the two dimensional connectivity. The organic layers contain pairs of centrosymmetrically related, and therefore head to tail, face to face molecules. Each molecule of such a pair participates in the formation of short S⋯S contacts with a molecule of a centrosymmetrically related neighboring molecule pair thus creating chains of molecules. The connectivity within the organic layer is completed by C–H⋯π contacts between the chains. Connectivity between the organic and inorganic layers is achieved by participation of the thione S in the coordination of one type of Hg.

Four binuclear dmit complexes of palladium(II), having μ-X or -S bridges, have been synthesized and characterized. The complexes, (Bu 4 N)[Pd 2 X 2 (dmit) 2 ] (X=Cl ( 1 ) and Br ( 2 )), were prepared by metathesis reaction from bridged precursors, [(Bu 4 N) 2 (Pd 2 X 6 )]. The complexes, D 2 [Pd 2 (Sph) 2 (dmit) 2 ] (D=Bu 4 N ( 3 ) and Et 4 N ( 4 )), were prepared by cracking reaction of polymeric precursor [Pd 2 Cl 2 (Sph) 2 ] n . The benzenthiolate-bridged anions of 3 and 4 exhibit dinegative ionic charge (2−), which can be deduced from the precursor. On the other hand, the halogen-bridged anions of 1 and 2 are oxidized during the synthetic reaction and show uninegative ionic charge (1−).

Four ‘unsymmetric’ complexes of palladium(II), [Pd(L)Cl 2 ] and [Pd(L)(dmit)], have been synthesized and characterized [L=4′,5′-diaza-9′-(4,5-bis(methylthio)-1,3-dithiole-2-ylidene)-fluorene (L 1 ) and 4′,5′-diaza-9′-(4,5-ethylenedithio-1,3-dithiole-2-ylidene)-fluorene (L 2 )]. Single crystal structure of [Pd(L 1 )Cl 2 ] was determined, in which, the atoms of the molecule, except two methyl-groups, are conjugated in a quasi-plane. The planar molecules are further stacked forming two unequivalent columns with C⋯C, S⋯C and S⋯Cl contacts. The differences between dichloro complexes and dmit complexes in IR, UV and oxidation properties were discussed in detail. The dmit complexes exhibit LLCT band from dmit (donor) to π* of L 1 (acceptor).

The preparation and crystal structure of a large wheel-shaped indium-telluride compound are reported. The inorganic cluster is decorated with 1,2-diaminocyclohexane molecules that play an important role in the formation of the nanoring. A related new 1D polymeric InTe compound is also presented in order to understand the effect of acidity on the formation of the ring structure.

Two sets of copper(I) halide complexes with the new type of ligands, 4′,5′-diaza-9′-(4,5-ethylenethio-1,3-dithiole-2-ylidene)fluorene (L1) and 4′,5′-diaza-9′-(4,5-dimethylthio-1,3-dithiole-2-ylidene)fluorene (L2), were prepared, [Cu(L1)X] (X=Cl, Br, I) and [Cu(L2)nX] (X=Cl, Br, n=1; X=I, n=0.5). The insoluble coordination polymers were characterized on the basis of the data obtained from elemental analyses, atomic absorption, IR, UV-Visible and fluorescence spectra. The conductivity of the iodine-doped complexes was also studied at room temperature (10−6–10−8 S cm−1). Ligand-centered oxidation is considered to be the reason of the conductivity.

As a new polymer compound, [(ZnS)2(en)]∞ has been synthesized by solvothermal method from elemental sulfur and zinc(II) salt in ethylenediamine. Detailed characterizations of the new coordination polymer have been discussed. The compound reveals a comparative good photocatalytic activity for degradation of dyestuff X-2R.

As most of the chalcogenidometalate anions are well-known electron-rich systems, design and preparation of ion pair compounds, by integrating an organic acceptor (A) with an inorganic chalcogenidometalate donor (D), are an attractive strategy to obtain new functional materials. We report herein the single-crystal structures and properties of three new ion pair charge-transfer (IPCT) compounds by incorporating thiogermanates with methylviologen (MV(2+), N,N'-dimethyl-4,4'-bipyridinium dication), [MV]2Ge4S10·xSol (Sol = solvent). Sharp and fast solvent-induced color changes and switchable fluorescence emission are observed for the compounds. The weak interactions that relate to the solvent and ions in the structures are likely the key points to modulate the cation-anion charge-transfer. A photocurrent response is observed for the photoelectric system of the IPCT compound upon repetitive switching of light on and off.