Metal–Organic Frameworks Constructed from Versatile [WS4Cux]x−2 Units: Micropores in Highly Interpenetrated Systems

Five metal–organic frameworks (MOFs) formed by [WS₄Cu_x]^x?2 secondary building units (SBUs) and multi‐pyridyl ligands are presented. The [WS₄Cu_x]^x?2 SBUs function as network vertexes showing various geometries and connectivities. Compound 1 contains one‐dimensional channels formed in fourfold interpenetrating diamondoid networks with a hexanuclear [WS₄Cu₅]³⁺ unit as SBU, which shows square‐pyramidal geometry and acts as a tetrahedral node. Compound 2 contains brick‐wall‐like layer also with a hexanuclear [WS₄Cu₅]³⁺ unit as SBU. The [WS₄Cu₅]³⁺ unit in 2 is a new type of [WS₄Cu_x]^x?2 cluster unit in which the five Cu⁺ ions are in one plane with the W atom, forming a planar unit. Compound 3 shows a nanotubular structure with a pentanuclear [WS₄Cu₄]²⁺ unit as SBU, which is saddle‐shaped and acts as a tetrahedral node. Compound 4 contains large cages formed between two interpenetrated (10,3)‐a networks also with a pentanuclear [WS₄Cu₄]²⁺ unit acting as a triangular node. The [WS₄Cu₄]²⁺ unit in 4 is isomeric to that in 3 and first observed in a MOF. Compound 5 contains zigzag chains with a tetrahedral [WS₄Cu₃]⁺ unit as SBU, which acts as a V‐shaped connector. The influence of synthesis conditions including temperature, ligand, anions of Cu^I salts, and the ratio of [NH₄]₂WS₄ to Cu^I salt on the formation of these [WS₄Cu_x]^x?2‐based MOFs were also studied. Porous MOF 3 is stable upon removal and exchange of the solvent guests, and when accommodating different solvent molecules, it exhibits specific colors depending on the polarity of incorporated solvent, that is, it shows a rare solvatochromic effect and has interesting prospects in sensing applications.     

Solid state synthesis of copper(I) thiotungstate cluster compounds at low heating temperatures. Crystal structures of [(n-Bu)4N]3-[WS4Cu3Cl3Br] and [Et4N]4[WS4Cu4I6]

Summary Reaction of [NH₄]₂[WS₄] with CuX (X = Cl or I) and R₄NX (R = Et or n-Bu) in the solid state gave two new bimetallic compounds with W:Cu compositions from 1:3 to 1:4. Compound (1), [(n-Bu)₄N]₃[WS₄Cu₃Cl₃Br], crystallizes in the hexagonal space group R3c with a = 17.051(5), c = 38.372(5) Å, V = 9661.8 ų, Z = 6. The cluster anion of (1) comprises a cubane-like cluster core [WS₃Cu₃Br] of C₃ symmetry with a Cl atom attached to each of the three Cu atoms and one terminal sulphido ligand attached to the W atom. Compound (2), [Et₄N]₄[WS₄Cu₄I₆], crystallizes in the monoclinic space group C2/m with a = 29.702(6), b = 12.7887(5), c = 15.327(3)Å, = 99.69(2), V = 5738.1 ų, Z = 4. In the cluster anion of (2), four edges of the WS₄ core are coordinated by four Cu atoms, giving a WS₄Cu₄ aggregate of approximate C_2V symmetry.     

Elektronenüberführungs-, IR-, RAMAN- und Photoelektronenspektren sowie röntgenographische Untersuchungen von Tl2MO2S2 Tl2MOS3und TB2MS4 (MMo,W) sowie Photoelektronenspektren zahlreicher Übergangsmetallverbindungen zum Vergleich

The electron transfer, i. r., RAMAN and photoelectron spectra and the powder diagrams of Tl₂MO₂S₂, TI₂MOS₃ Tl₂MS₄ (M = Mo, W) and, in comparison, the photoelectron spectra of some other transition metal compounds The electron transfer, i. r., RAMAN and photoelectron spectra and the powder diagrams of Tl₂MoO₂S₂, Tl₂WO₂S₂, Tl₂MoOS₃, Tl₂WOS₃, Tl₂MoS₄ and Tl₂WS₄ are reported and discussed. The different methods allow a discussion of the strong polarising effect of the Tl(I) cation on the anions. For the purpose of comparison the photoelectron spectra of the salts Tl₃MX₄ (M = V, Nb, Ta; X = S, Se); Tl₂MO₄ (M = Mo, W); Cs₂MX₄, (M = Mo, W; X = S, Se) and other similar salts were also measured.     

Zwei- und dreikernige Komplexe des WS42– mit Tricarbonylrhenium(I)- und -mangan(I)-Fragmenten: Struktur,Spektroskopie und Elektrochemie

Di- and Trinuclear Complexes of WS₄^2– with Tricarbonylrhenium(I) and -manganese(I) Fragments: Structure, Spectroscopy, and Electrochemistry The reaction of (NEt₄)₂WS₄ with two equivalents of M(CO)₅(O₃SCF₃), M = Mn or Re, in acetonitrile yielded the crystallographically characterized neutral compounds [(CH₃CN)(OC)₃M(μ-S₂WS₂)M(CO)₃(NCCH₃)]. The individual molecules are chiral and contain WS₄ and MS₂(CO)₃(CH₃CN) moieties in approximately tetrahedral and octahedral configurations, respectively. Vibrational and electronic absorption spectra are in agreement with the crystal structure, comparable results were obtained for trinuclear complexes [(L)(OC)₃Re(μ-S₂WS₂)Re(CO)₃(L)](NEt₄)₂, L = Cl^– or CN^–, and for the dinuclear systems [(WS₄)Re(CO)₃(CH₃CN)](NEt₄) and [(WS₄)Re(CO)₃Cl](NEt₄)₂. Electrochemical processes are irreversible due to the lability of acetonitrile or chloride ligands in corresponding complexes, however, the cyanide compound [(NC)(OC)₃Re(μ-S₂WS₂)Re(CO)₃(CN)]^2– showed reversible one-electron reduction to a first tetrathiotungstate(V) species as detected by UV/Vis/IR spectroelectrochemistry.     

Strukturchemische Untersuchungen von Monammin-Kupfer(I)-Komplexen: [CuNH3]2[Pt(CN)6], [CuNH3]2[Pt(CN)4] und Cu3[Co(CN)6]-2 NH3

Structurally Chemical Investigation of Monoammin Copper (I) Complexes : [CuNH₃]₂[Pt(CN)₆], [CuNH₃]₂[Pt(CN)₄] and Cu₃[Co(CN)₆] · 2NH₃ The preparation and the properties of [CuNH₃]₂[Pt(CN)₆], [CuNH₃]₂[Pt(CN)₄] and Cu₃[Co(CN)₆] · 2NH₃ are described. I.R. and Raman spectra have been recorded and assigned. According to X-ray powder diagrams, [CuNH₃]₂[Pt(CN)₆] crystallizes in the trigonal space group D–P3 ml, a = 7.771, c = 5.988 Å, Z = 1. According to the spectroscopic and crystallographic data, it is concluded that the Cu_I ion is coordinated with one NH₃ group and with the N atoms of the cyanometallate anions. The coordination number of the Cu⁺ is 4 in [CuNH₃]₂[Pt(CN)₆] and 3 in [CuNH₃]₂[Pt(CN)₄]. In the Cu₃[Co(CN)₆] · 2 NH₃ complex two Cu atoms have the coordination number 2, the third Cu atom 4.     

Ternäre Thalliumplatin- und Thalliumpalladiumchalkogenide Tl2M4X6. Synthesen,Kristallstruktur und Bindungsverhältnisse

Ternary Thallium Platinum and Thallium Palladium Chalcogenides Tl₂M₄X₆. Syntheses, Crystal Structures, and Bonding Relations The compounds Tl₂Pt₄S₆, Tl₂Pt₄Se₆, Tl₂Pt₄Te₆ and Tl₂Pd₄Se₆ can be synthesized by a melting reaction from the elements or by the reaction of thallium carbonate, transition metal powder and chalcogen powder in the temperature range between 400°C and 950°C. X-Ray investigations on single crystals and powdered samples revealed a new structure type for the compounds, that can be understood as stacking variant of the already known atom arrangement of the alkaline metal platinum chalkogenides A₂Pt₄X₆ (A ? alkaline metal, X ? S, Se). The short distances thallium-platinum and thallium-palladium, respectively, as well as the results of Extended-Hückel-calculations indicate covalent bonds between the main group and transition metal atoms.     

Radiale Verteilungsfunktionen. V. Strukturuntersuchungen an nichtkristallinem Molybdäntrisulfid,Wolframtrisulfid und Molybdäntriselenid

Radial Distribution Functions. V. Structural Studies on Noncrystalline Molybdenum Trisulfide, Tungsten Trisulfide, and Molybdenum Triselenide The noncrystalline compounds MoS₃, WS₃ and MoSe₃ were studied by X-ray diffraction. From the diffuse intensities radial distribution functions were computed and interpreted in terms of pair distribution functions. The substances are built up by microcrystallites which contain three metal atoms and are bridged statistically to each another. The shortest metal chalcogen distances d(MoS) ≈ d(WS) = 2.40 ± 0.05 Å and d(MoSe) = 2.50 ± 0.05 Å are significantly longer than in MS- or MSe compounds with a d° configuration of the metal respectively and metal–metal distances within the microcrystallites are less than 3 Å.     

Synthesis of a new salt containing polyoxometallate anion and M?Cu?S cluster cation [MS4Cu4(γ-MePy)8][M6O19] (M = Mo,W). Crystal structure of [WS4Cu4(γ-MePy)8] [W6O19]

Reactions of (NH₄)₂MS₄, AgBr and CuBr in γ-methylpyridine produced one new compound, [MS₄Cu₄(γ-MePy)8][M₆O₁₉] (1, M = W; 2 , M = Mo), of which 1 was characterized by single crystal X-ray analysis. The crystal data: orthorhombic, Pbcn, a = 15.434(4), b = 16.732(2), c = 28.657(7) Å, V = 7400.8(8) ų, Z = 4 , R = 0.072 for 3121 independent data. The compound is the first example which contains both polyoxotungstate anion and heteropolynuclear cluster cation. In the structure of the cation four edges of the tetrahedral WS^2?₄ core are coordinated by four copper atoms, giving a WS₄Cu₄ aggregate of approximate D_2h symmetry. The differences between the reaction of Cu⁺ with MS^2?₄ and that of Ag+ with MS^2?₄ in pyridine and its derivatives are discussed.     

Thiochlorowolframate von Wolfram(V) und -(VI). Die Kristallstrukturen von PPh4[WSCl4] und (PPh4)2[WS2Cl4] · 2 CH2Cl2

Thiochlorowolframates with Tungsten(V) and (VI). Crystal Structures of PPh₄[WSCl₄] and (PPh₄)₂[WS₂Cl₄] · 2 CH₂Cl₂ Diamagnetic (NEt₄)₂[WSCl₄]₂, having tungsten atoms linked via sulfur atoms, is obtained by the reaction of WCl₅ with NEt₄SH as well as by the reduction of WSCl₄ with NEt₄I in dichloromethane. If the reduction is performed with PPh₄I, PPh₄[WSCl₄] with monomer anions is formed. Reaction of WCl₆ with H₂S in dichloromethane yields brown, insoluble WS₂Cl₂ which has terminal W?S groups and bridging W? S? W groups according to its IR spectrum. WS₂Cl₂ and PPh₄Cl react to afford PPh₄[WS₂Cl₃] · 2 CH₂Cl₂ and (PPh₄)₂[WS₂Cl₄] · 2 CH₂Cl₂. IR spectra are reported. The crystal structures of PPh₄[WSCl₄] and (PPh₄)₂[WS₂Cl₄] · 2 CH₂Cl₂ were determined by X-ray diffraction. PPh₄[WSCl₄]: tetragonal, space group P4/n, Z = 2, a = 1292.3 pm, c = 763.2 pm; R = 0.054 for 898 observed reflexions. The [WSCl₄]^? ion has the structure of a square pyramid with a rather short W?S bond of 206 pm length. (PPh₄)₂[WS₂Cl₄] · 2 CH₂Cl₂: triclinic, space group P1 , a = 1017.7, b = 1114.5, c = 1243.4 pm, α = 70.61, β = 79.73, γ = 80.80°; R = 0.076 for 1804 reflexions. The [WS₂Cl₄]^2? has cis configuration; as it is situated on an inversion center it shows positional disorder.     

Exfoliated transition metal dichalcogenides (MoS2, MoSe2, WS2, WSe2): An electrochemical impedance spectroscopic investigation

Owing to the enthralling properties which transition metal dichalcogenides present, they are facing immense scientific interest from researchers. Till date, these two-dimensional materials have been assessed for a wide array of different applications and there are various synthetic methods of attaining them in their respective bulk and exfoliated forms. Herein, we explore the effects of lithium ion intercalation exfoliation process on the charge transfer resistance of transition metal dichalcogenide materials (MoS₂, MoSe₂, WS₂ and WSe₂). We also show that electrochemical activation of the transition metal dichalcogenides results in decreased resistance towards charge transfer, as demonstrated by electrochemical impedance spectroscopy.     

Über Kupfer(I)-sulfat Cu2SO4. Darstellung und thermische Eigenschaften

Preparation and Thermal Properties of Copper(I) Sulfate Cu₂SO₄ Copper(I) sulfate Cu₂SO₄ can be prepared in high purity by reaction of Cu₂O with dimethyl sulfate (CH₃)₂SO₄ at 160°C in an argon atmosphere. Using an extremely fine grained Cu₂O, as obtained by reduction of cupric acetate with hydrazine, and a reaction time of 10 minutes a Cu₂SO₄ is obtained that contains less than 1% Cu₂O. Longer reaction times lead to partial decomposition of the Cu₂SO₄ to Cu(met.) and CuSO₄. In a closed system Cu₂SO₄ melts at about 400°C, however, the melt rapidly decomposes to Cu and CuSO₄, solidifying simultaneously. When heated in a thermoanalyzer in flowing argon or in a vacuum, Cu and CuSO₄ react under liberation of SO₂. Increasing the temperature leads to CuO in three steps, which converts to Cu₂O when heated to 1000°C. The question of formation of Cu₂SO₄, occasionally mentioned in the literature, being responsible for the liquid phases observed in the system Cu? S? O at temperatures below 500°C, is discussed.     

Schwingungsspektren und strukturchemie von heterometall-komplexen und -clustern mit thiometallat-liganden

The thioanions of the early transition metals, e.g. MoOS₃^2?, WOS₃^2?, MoS₄^2? and WS₄^2?, form hetero-metal complexes, which are interesting because of their electronic properties and their relevance to problems of bioinorganic chemistry. Their vibrational spectra are discussed in relation to the molecular structure of the compounds and especially to the wide variety of the coordination types of the thiometalate ligands. It is demonstrated that vibrational spectroscopy (especially Raman and resonance Raman) is a powerful tool for the determination of the local symmetry of the thioanions in polynuclear coordination compounds.     

Über Verbindungen des Typs Cu3MSxSe4−x(M = Nb,Ta). Bestimmung der Kristallstruktur von Cu3TaSSe3

On Compounds of the Type Cu₃MS_xSe_4?x(M = Nb, Ta). Determination of Crystal Structure of Cu₃TaSSe₃ The preparation, X-ray data, vibrational, and electronic spectra of Cu₃NbS₃Se, Cu₃NbS₂Se₂, Cu₃NbSSe₃, Cu₃TaS₃Se, Cu₃TaS₂Se₂, and Cu₃TaSSe₃ are reported. The powder patterns of all compounds could be indexed on the basis of a simple cubic lattice. The compounds crystallize in pseudo-sulvanite type with the sulfur and selenium atoms in random distribution.     

Neue Oxocuprate (I). Über Cs3Cu5O4, Rb2KCu5O4, RbK2Cu5O4 und K3Cu5O4

New Oxocuprates(I). On Cs₃Cu₅O₄, Rb₂KCu₅O₄, RbK₂Cu₅O₄ and K₃Cu₅O₄ Cs₃Cu₅O₄ light yellow, powder as well as single crystals [a = 10.313(9), b = 7.630(1), c = 14.750(4) Å, β = 106.48(6)°], Rb₂KCu₅O₄ [a = 9.724(2), b = 7.443(0), c = 14.246(2) Å, β = 106.78(8)°], RbK₂Cu₅O₄ [a = 9.561(1), b = 7.411(0), c = 14.111(1) Å, β = 106.76(7)°] and K₃Cu₅O₄ [a = 9.422(1), b = 7.364(1), c = 13.995(2) Å, β = 107.00(2)°] are new prepared. The colour of the powders becomes lighter according to the sequence showed above. K₃Cu₅O₄ shows pale yellow. The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed.     

Koexistenzbeziehungen,Darstellung und Eigenschaften ternärer Phasen im System Cu/Mo/O

Coexistence Relations, Preparation and Properties of Ternary Compounds in the System Cu/Mo/O The phase diagram of the ternary system Cu/Mo/O is presented at 773 K. The compounds CuMoO₄, Cu₃Mo₂O₉, Cu₄Mo₅O₁₇, Cu₆Mo₅O₁₈, Cu_4–xMo₃O₁₂, and Cu_xMoO₃ are found to be thermodynamical stable. The homogeneity range of Cu_4–xMo₃O₁₂ runs to x = 0.1–0.2. Single crystals of CuMoO₄ and Cu₃Mo₂O₉ were grown by chemical transport reactions with TeCl₄, Cl₂, HCl, and Br₂ as transport agent. The results were compared with thermochemical calculations. The decomposition of CuMoO₄ and Cu₃Mo₂O₉ was investigated with thermal analysis and decompositon pressure measurements.     

Vanadium‐Doped WS2 Nanosheets Grown on Carbon Cloth as a Highly Efficient Electrocatalyst for the Hydrogen Evolution Reaction

Two‐dimensional transition‐metal dichalcogenides have been widely studied as electrocatalysts for the hydrogen evolution reaction (HER). However, limited active sites and poor conductivity hinder their application. To solve these disadvantages, heteroatom doping has attracted wide attention because it can not only increase the active sites but also affect the intrinsic catalytic properties of the electrocatalyst. Herein, we grew vanadium‐doped WS₂ nanosheets on carbon cloth (V‐WS₂/CC) as an electrocatalyst for HER under acidic and alkaline conditions. With a proper vanadium doping concentration, the electrochemical surface areas of V_0.065‐WS₂/CC were 9.6 and 2.6 times as large as that of pure WS₂ electrocatalyst under acidic and alkaline conditions, respectively. In addition, the charge‐transfer resistance also decreased with moderate vanadium doping. Based on this, the synthesized vanadium‐doped WS₂ nanosheets exhibited good stability with high HER catalytic activity and could reach a current density of 10 mA cm⁻² at overpotentials of 148 and 134 mV in 0.5 m H₂SO₄ and 1 m KOH, respectively. The corresponding Tafel slopes were 71 and 85 mV dec⁻¹. Therefore, our synthesized vanadium‐doped WS₂ nanosheets can be a promising electrocatalyst for the production of hydrogen over a wide pH range.     

Über Oxobismutate. Zur Kenntnis von Na3BiO4 und Na3SbO4

On oxobismuthates. The compounds Na₃BiO₄ and Na₂SbO₄ Na₃BiO₄ crystallizes monoclinic in C⁴_2h; a = 5.87₁ b = 6.69⁶, c = 5.65₀ Å and β = 109,8° with Z = 2. We have a variant of the NaCl type, forming chains ¹_∞[BiO_4/2+2/1] along [001]. The MADELUNG part of lattice energy (MAPLE) of Na₃BiO₄ and different other structure models are calculated und discussed. Na₃SbO₄[a = 5.79₅, b = 6.59₅, c = 5.41₈ Å, β = 109.4°] is isotypic with Na₃BiO₄.     

Synthesis and characterization of the bimetallic polymers [MS4Ag2(Hmimt)2]n (where M = Mo or W,Hmimt = 1-methylimidazoline-2(3H)-thione): crystal structures of [WS4Ag2(Hmimt)2]n and [Ag2I2(Hmimt)]n

The title compounds were synthesized by the reactions of [NH₄]₂[MS₄] (M = Mo, W), AgI and Hmimt in acetone and characterized by IR, ¹H NMR and UV–Vis spectroscopy. The polymeric structure of [WS₄Ag₂(Hmimt)₂]_n was determined by X-ray crystallography. In this compound, there are two distinctly different coordination modes for the silver atoms. One Ag atom has a pseudo-tetrahedral geometry with one terminal monodentate-S Hmimt, two μ₂-S bridging Hmimt and one S atom of a monodentate WS₄ unit. The other is surrounded by four sulfur atoms belonging in pairs to two WS₄ fragments; the coordination geometry is distorted tetrahedral. The [WS₄Ag₂(Hmimt)₂]_n polymer represents the first example of tetrathiometalate anions [MS₄]²⁻ (M = Mo, W, or V) coordinated to another metal atom in a monodentate fashion. In both crystal structures determined the Hmimt ligands are present in the thione form, with coordination taking place via the sulfur atom only.     

Über die Darstellung von Tricyanmethanidometallbromiden und Organometalltricyanmethaniden durch Reaktionen mit Bromtricyanmethan BrC(CN)3

Different reactions of BrC(CN)₃ with metal bromides (MBr₄; M = Sn, Ti, Zr), metal organyles (SnR₄, MR₂ (R = C₂H₅, C₆H₅; M = Zn, Cd), C₆H₅HgBr) and with phosphorus tribromide are reported. These reactions lead to the formation of new compounds of the types MBr₃NCC(CN)₂, R₃MNCC(CN)₂, RMNCC(CN)₂ and PBr₄NCC(CN)₂, respectively. The structures of the new compounds are discussed, using results of infrared spectroscopic measurements. Mostly the pseudohalide group C(CN)₃ is bonded to the metal via the nitrogen of a cyano group. Unsolubility and IR spectra are characterizing the compounds of the types MBr₃NCC(CN)₂ and RMNCC(CN)₂ as coordination polymers. IIb-metal derivatives form pyridine complexes [RMNCC(CN)₂(C₅H₅N)₂].     

Über Polyphosphide von Chrom,Mangan, Ruthenium und Osmium. Synthese und Kristallstruktur von RuP4 und OsP4

On Polyphosphides of Chromium, Manganese, Ruthenium, and Osmium. Synthesis and Crystal Structure of RuP₄ and OsP₄ The new compounds RuP₄ and OsP₄ were prepared by annealing thr elemental components in the presence of iodine. Well developed crystals were obtained by reaction of the components in liquid tin. RuP₄ is triclinic, space group P1 , a = 7.519(8), b = 7.145(7), c = 4,713(5) Å, α = 100.48(10), β = 90.35(10), γ = 111.08(11)°, Z = 3. The structure was determined and refined from diffractometer data: R = 0.049 for 3532 F values, Ru is octahedrally surrounded by P. The P atoms are in tetrahedral coordination of Ru and P. All near neighbour interactions can be interpreted as two-electron bonds. This results in formal oxidation number +2 for Ru (d⁶ system). Thus, while the metal atoms in the related compounds CrP₄(Cr in d₄ configuration) and MnP₄ (d₅ configuration for Mn) form Cr chains and Mn pairs respectively, no short metal-metal interactions are present in RuP₄ · OsP₄ is isotypic with RuP₄ · CrP₄ and MnP₄ were prepared in the presence of iodine or from the tin melt without the application of pressure.