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Mixing an aqueous solution of K8[Nb6O19]⋅16H2O with a DMSO/H2O solution of Cu(ClO4)2 · 6 H2O and cyclen at room temperature afforded crystallization of blue crystals of [(Cu(cyclen))6Nb6O19]⋅[ClO4]4·≈4H2O after slow evaporation of the solvents. The crystal structure contains the Lindqvist anion [Nb6O19]8– which is covalently expanded by six symmetry-related [Cu(cyclen)]2+ complexes via Nb-μ 2-O-Cu bridges yielding the positively charged [(Cu(cyclen))6Nb6O19]4+ cluster shell. The ClO4 − anions and crystal water molecules reside in the empty spaces of the packed clusters. The compound shows two electronic d-d transitions at energetic positions explaining the blue color.

The synthesis, crystal structures and properties of two alkali metal 3-nitrohydrogenphthalates obtained by a 1:2 reaction of M2CO3 (M = K or Na) with 3-nitrophthalic acid (LH2) are reported. In the anhydrous potassium coordination polymer [K(LH)] (LH = 2-carboxy-3-nitrobenzoate) 1, the K+ cation is bonded to nine oxygen atoms from six symmetry related (LH)– ligands resulting in a distorted {KO9} coordination polyhedron. Five of the six oxygen atoms including a nitro oxygen atom of the crystallographically unique 2-carboxy-3-nitrobenzoate are involved in metal binding. The μ6-bridging mode of (LH)– places the K+ cations into the layers of the two-dimensional (2D) coordination polymer. Each {KO9} polyhedron in 1 shares edges with two other polyhedra along the b and c axes. A low temperature structure redetermination of [Na(L#H)(H2O)3]·H2O (L#H = 2-carboxy-6-nitrobenzoate) 2 has revealed that the (L#H)− anion is bonded to the Na+ cation in a monodentate fashion via the carbonyl oxygen atom of the –COOH group and two of the three unique aqua ligands exhibit a bridging bidentate mode stabilizing a chain polymer. The structure of compound 2 thus consists of chains of edge-sharing {NaO6} octahedra. Thermal decomposition of 1 or 2 results in the formation of metal carbonate residues.

The title compounds were prepared by precipitation from acidic solutions of the reactants in acetone/water. Bi(S2CNH2)2Cl (1) crystallizes in the non-centrosymmetric trigonal space group P32 with a = 8.6121(3) and c = 11.1554(4) Å, Z = 3; Bi(S2NH2)2SCN (2) in P21/c (monoclinic) with a = 5.5600(2), b = 14.3679(5), c = 12.8665(4) Å, and β = 90.37(3)°. In the crystal structure of 1 Bi3+ is in a sevenfold coordination of two bidentate and one monodentate S2CHNH2 − anions with an asymmetric coordination pattern of five Bi–S and two Bi–Cl− bonds. The linkage of these polyhedra via common Cl–S edges leads to a 1D polymeric structure with undulated chains propagating in the direction [001]. These chains are linked by strong and medium strong hydrogen bonds forming the 3D crystal structure. In the crystal structure of 2 the Bi3+ cation is in an eightfold coordination. The polyhedron can be described as a significantly distorted tetragonal anti-prism, capped by an additional S atom. Two of these prisms share a common quadrilateral face to form a “prism-double” (Bi2S10N2). These building units are linked by common edges, and the resulting 1D infinite angulated chains propagate along [100]. By contrast to organo-dithiocarbamate compounds, where C–H···X bridges are dominant, the interchain connections in the crystal structures of 1 and 2 are formed exclusively via N–H···S, N–H···Cl, and N–H···N interactions, generating the 3D networks. A significant eccentricity of the Bi3+ cation in the crystal structures of both complexes is observed. Both compounds emit light in the orange range of the electromagnetic spectrum.

The reaction of Na2MoO4·2H2O with 2-amino-2-(hydroxymethyl)propane-1,3-diol (LH) in water at room temperature results in the formation of the heterometallic coordination polymer [Mo2O6L2(Na2(H2O)4)]·2H2O 1 (L = 2-amino-3-hydroxy-2-(hydroxymethyl)propan-1-olato). The structure of 1 consists of a neutral (Mo2O6) unit located on an inversion center. The Mo atoms exhibit hexa-coordination and are bonded to two terminal and two bridging oxido ligands, an alkoxide oxygen and the amine N atoms of an anionic ligand L– resulting in the formation of an edge-sharing {Mo2O8N2} bioctahedron. The Na+ cations of a centrosymmetric bis(μ2-aqua)-bridged (Na2(H2O)4)2+ unit are penta-coordinated and bonded to two symmetry related L– ligands via the oxygen atoms of their OH groups. The µ3-bridging tetradentate binding mode of L– results in the formation of a two-dimensional heterometallic coordination polymer. The constituents of 1 viz. (Mo2O6), (L)–, (Na2(H2O)4)2+ and lattice water molecules are interlinked with the aid of three varieties of hydrogen bonding interactions. The corresponding tungstate reported recently has been obtained through a similar synthetic protocol and is isostructural.

The new compound K2[Ni(dien)2]{[Ni(dien)]2Ta6O19}·11 H2O crystallized at room temperature applying a diffusion based reaction in a H2O/DMSO mixture using K8{Ta6O19}·16 H2O, Ni(NO3)2·6H2O and dien (diethylenetriamine). In the crystal structure, the Lindqvist-type anion [Ta6O19]8– is structurally expanded by two octahedrally Ni2+-centered complexes via three Ni–µ 2-O–Ta bonds thus generating the new {[Ni(dien)]2Ta6O19}4– anion. Two KO8 polyhedra share a common edge to form a K2O14 moiety, which connects the {[Ni(dien)]2Ta6O19}4– cluster shells into chains. The isolated [Ni(dien)2]2+ complexes are located in voids generated by the structural arrangement of the chains. An extended hydrogen bonding network between the different constituents generates a 3D network. The crystal water molecules can be thermally removed to form a highly crystalline dehydrated compound. Partial water uptake leads to the formation of a crystalline intermediate with a reduced unit cell volume compared to the fully hydrated sample. Water sorption experiments demonstrate that the fully dehydrated sample can be fully reconverted to the hydrated compound. The crystal field splitting parameters for the octahedrally coordinated Ni2+-centered complexes have been evaluated from an UV/Vis spectrum yielding D q = 1056 cm−1 and B = 887 cm−1.

Syntheses were performed at room temperature using Ni(NO3)2·6H2O, cyclam (cyclam = 1,4,8,11-tetraazacyclotetradecane) and the precursors Li8[Nb6O19]· ≈22H2O or Na7[HNb6O19]·15H2O in a DMSO-H2O mixture. Yellow crystals of the new compound {[Ni(cyclam)]2H4Nb6O19}·12H2O could be obtained after one week applying the Li+ or Na+ salt as starting materials. The crystal structure is unique in polyoxoniobate (PONb) chemistry and displays two interpenetrating three-dimensional (3D) networks. The [Nb6O19]8– anion is expanded by four Ni2+ centered complexes via Ni–O bonds to terminal O2− anions of the hexaniobate anion. The 3D networks are generated by further Ni–O bond formation between neighboring [Nb6O19]8− anions. The remaining void space is occupied by H2O molecules which form a water cluster.

The room temperature reaction of Hg(NO3)2 · H2O, cyclam (cyclam = 1,4,8,11-tetraazacyclotetradecane) and K8{Nb6O19} · 16 H2O in a mixture of H2O and DMSO led to crystallization of the novel compound {[Hg(cyclam)]6Nb6O19}(NO3)4 · 14 H2O, which is the first mercury containing polyoxoniobate. The structure consists of a {Nb6O19}8− cluster core which is expanded by six [Hg(cyclam)]2+ complexes via Hg–μ 2-O–Nb bond formation. The title compound contains a positively charged polyoxoniobate cluster. The crystal water molecules form small aggregates by O–H · · · O hydrogen bonding which are joined into larger aggregates by N–O · · · H–O hydrogen bonding integrating the nitrate anions.

The first mixed germanato-antimonato derivative of the {V14E8O42} (E=semi-metal) cluster archetype has been synthesized under hydrothermal conditions and isolated as {Ni(phen)3}2[α-VIV14SbIII5GeIV3O42(OH)3(H2O)]· ≈16H2O (phen=1,10-phenanthroline). In the cluster anion, seven of the eight hetero-metal positions are occupied by disordered Ge/Sb atoms, while one position is fully occupied by Sb atoms. The [V14Sb5Ge3O42(OH)3(H2O)]6−anions are arranged in pairs with remarkably short inter-cluster Sb···O contacts. Bond valence sum calculation strongly suggests that the Sb···O contact must be taken into account as a weak bond. The magnetic properties are dominated by strong intra-cluster antiferromagnetic exchange interactions, and the cluster anion is magnetically quasi-isolated from the spins of the Ni2+complex cations.

Results of combined synchrotron X-ray diffraction and pair distribution function experiments performed on the layered compound CrTe3 provide evidence for a short range structural distortion of one of the two crystallographically independent CrTe6 octahedra. The distortion is caused by higher mobility of one crystallographically distinct Te ion, leading to an unusual large Debye Waller factor. In situ high temperature X-ray diffraction investigations show an initial crystallization of a minor amount of elemental Te followed by decomposition of CrTe3 into Cr5Te8 and Te. Additional experiments provide evidence that the Te impurity (4Te16 structural building units. An abrupt distortion of the structure occurs at T≈250 K, which then remains nearly constant down to 100 K. The structural distortion affects the spin exchange interactions between Cr3+ cations. A significant splitting between field-cooled (fc) and zero-field-cooled (zfc) magnetic susceptibility is observed below about 200 K. Applying a small external magnetic field results in a substantial spontaneous magnetization, reminiscent of ferro- or ferrimagnet exchange interactions below ~240 K. A Debye temperature of ~150 K was extracted from heat capacity measurements.

The new compound [Mn2(bipy)4SbS4](ClO4) was prepared by a new synthetic route for the preparation of thioantimonates(V) that can be used even at room temperature. Mixing aqueous solutions of [Mn(bipy)3](ClO4)2 and Na3SbS4 · 9H2O leads to immediate crystallization of the pure compound. In the structure an SbS4 3– anion acts as a tetradentate bridge connecting two Mn2+ cations of [Mn(bipy)3]2+ complexes (bipy = 2,2′-bipyridine). The compound features a hitherto unknown [Mn2(bipy)4SbS4]+ cation. Bipy ligands of adjacent cations are arranged parallel to each other leading to weak off-center parallel π-π interactions stabilizing the crystals. Magnetic measurements indicate weak antiferromagnetic exchange interactions between the Mn2+ centers.

The compound {[Cu(C5H14N2)2]3[V15As6O42(H2O)]} was synthesized under solvothermal conditions. During the reaction the VV species of NH4VO3 are reduced to VIV providing the 15 reduced VIV centers in the anionic cluster. The compound crystallizes in the non-centrosymmetric orthorhombic space group P212121 with four formula units in the cell, V =9464:8(4) Å3. The structure features [V15As6O42(H2O)]6- anions which are joinded by Cu2+-centered complexes to form linear chains. If a long Cu-O bond is considered as weak intermolecular interaction a three-dimensional network is generated. The compound is partially soluble in water as evidenced by UV/Vis spectroscopy and mass spectra. The magnetic susceptibility of the compound is dominated by strong intra-cluster antiferromagnetic exchange interactions.

A new metastable compound Cr3Sb was synthesized as thin film starting from modulated elemental reactant layers. The new compound is cubic and crystallizes in the A15 structure (Cr3Si-type). A variation of the occupancy of the Sb position (0, 0, 0) was observed leading to a Cr-rich sample with formula Cr∼6Sb. In-situ X-ray diffraction and reflectivity investigations indicate an interdiffusion of the multilayers and crystallization of the new compound below 350°C. Calculations of the crystal structure and lattice parameter agree well with the experimental results. In addition the existence of a further metastable phase, a Heusler-like alloy, is discussed and supported by DFT calculations.

The new compound [Mn(dien)2][Mn(dien)SbS4]2 (dien=diethylenetriamine) was synthesized under solvothermal conditions. It crystallizes in the non-centrosymmetric monoclinic space group P21 with a=7.5736(5), b=19.1081(16), c=13.1174(11) Å, b =90:022(9) , V =1898.3(3) Å3, and Z =2. The crystal structure is composed of one [Mn(dien)2]2+ cation and an anionic chain composed of [SbS4]3- anions and [Mn(dien)2]2+ cations. The [SbS4]3- anions connect [Mn(dien)2]2+ ions in a μ2-fashion to form an undulated {[Mn(dien)SbS4]}-2 chain running along [001]. The Mn2+ ions in the chain are in a rare distorted rectangular pyramidal coordination environment with 3 N and 1 S atom forming the base and one S atom being located at the apex of the pyramid. The anionic chains and the cations alternate along [010]. Several relatively strong intra- and inter-chain N-H-S bonding interactions are observed. From the Raman spectrum the reduction of the ideal Td symmetry of the [SbS4]3- anions is obvious because more resonances occur than expected for the undistorted geometry

The new compound {Mn(dien)2}2[MnSb2S7] (dien = diethylenetriamine) was obtained under solvothermal conditions and crystallizes in the orthorhombic space group Pbca. The main structural motif is the [MnSb2S7]4– anion being constructed by a [MnS4]6– tetrahedron, a [SbIIIS3]3– and a [SbVS4]3– anion. Each thioantimonate anion shares one edge with the Mn2+ centered cation generating the [MnSb2S7]4– unit. The two independent Mn2+ cations in the two {Mn(dien)2}2+ complexes are in a distorted octahedral environment of two tridentate acting dien molecules. One cation displays the λδ–λλ-conformation and the other the δλ–λδ-conformation. Several intermolecular S···H—N bonding interactions are found between the cations and the anions.

Single crystals of RbBaTaS4 (1) and K2BaTa2S11 (2) were obtained from the reactions of Ta, with in situ formed fluxes of A2S3 (A = K, Rb), BaS, and S at 500 °C. Compound 1 crystallizes in the orthorhombic space group Pnma with a = 9.3286(5), b = 7.0391(4), c = 12.4365(7) Å, V = 816.6(1) Å3, Z = 4. Compound 2 crystallizes in the monoclinic space group P21/c with a = 14.5280(10), b = 12.6347(7), c = 17.5148(12) Å , β = 94.744(8)°, V = 3203.9(4) Å3, Z = 4. The structure of RbBaTaS4 (1) consists of isolated tetrahedral [TaS4]3− anions and Rb+ and Ba2+ cations. The Ba2+ cations are surrounded by nine sulfur atoms forming distorted tricapped trigonal prisms, whereas the Rb+ cations are in an irregular environment of ten sulfur atoms. The structure of K2BaTa2S11 (2) consists of two different dinuclear [Ta2S11] units which are separated by Ba2+ and K+ cations. The Ta atoms are coordinated by S2 2− and S2− ligands according to the mode [Ta2(μ2-S)(μ2-η2,η1- S2)2(η2-S2)2(S)2]4−. Each Ta atom is surrounded by seven sulfur ions forming strongly distorted pentagonal bipyramids. The two [TaS7] polyhedra share a common face in the [Ta2S11] unit. The K+ and Ba2+ cations are statistically distributed over the crystallographic sites. Compound 2 has also been characterized by UV/Vis diffuse reflectance, IR and Raman spectroscopy

A rich variety of inorganic-organic hybrid thioantimonates and thiostannates were prepared during the last few years under solvothermal conditions applying organic amine molecules or transition metal complexes as structure directors. In this review synthetic approaches to and structural features of these thiometallates are discussed. For thioantimonates(III) the structures range from well isolated thioanions to three-dimensional networks, whereas the structural chemistry of thiostannates(IV) is strongly dominated by the [Sn2S6]4− anion, and no three-dimensional thiostannate has been reported so far. In the structures of thioantimonates(III) several primary building units like the [SbS3] trigonal pyramid, the [SbS4] unit or even the [SbS5] moiety are joined by vertex- and/or edge-linkages to form building blocks of higher structural hierarchy like [Sb3S4] semi-cubes or SbxSx heterocycles. A pronounced difference between thioantimonate and thiostannate chemistry is the tendency of Sb(III) to enhance the coordination geometry via so-called secondary bonds. In most cases the environment of Sb(III) is better described as a 3+n polyhedron with n = 1 - 3. The thioantimonate(V) structural chemistry is less rich than that of thioantimonates(III), and the [SbS4]3− anion shows no tendency for further condensation. By applying suitable multidentate amine molecules, transition metal cations which normally prefer bonding to the N atoms of the amines can be incorporated into the thiometallate frameworks

The new thioantimonate [Mg(en)3][Sb4S7] containing for the first time a [Mg(en)3]2+ cation as structure-directing unit was synthesized under solvothermal conditions applying elemental Mg, SbCl3, S and ethylenediamine. The compound crystallizes in the monoclinic space group P21/c with a = 9.9267(6), b = 14.254(1), c = 17.259(1) A° , β = 102.611(7)°, V = 2383.1(3) °A3, Z = 4. In the structure trigonal SbS3 pyramids are joined to form an Sb3S3 ring. The rings are connected through SbS3 units yielding an undulated chain anion running along [001]. Considering so-called secondary Sb-S bonds, a layer-like thioantimonate anion is formed. The [Mg(en)3]2+ cations are located between the layers. Relatively short S・ ・ ・H-N contacts suggest hydrogen bonding interactions between the cation and the [Sb4S7]2− anion. The compound starts to decompose at about 220 °C. The optical band gap of 2.35 eV is in agreement with the orange color of the crystals. In the Raman spectrum prominent Sb-S resonances are seen between 250 and 400 cm−1 which can be assigned to different Sb-S vibrations

Two new thiostannates with Mn2+ ions were obtained under solvothermal conditions applying different amine concentrations. [Mn(C6H14N2)2(H2O)]2Sn2S6 (1) (C6H14N2 = 1,2-diaminocyclohexane, 1,2-dach) crystallizes in the monoclinic space group C2/c (with a = 23.7500(18), b = 15.5655(16), c = 12.1072(9) Å , β = 113.532(8)°, Z = 8). The second compound, [Mn(C6H14N2)2]- Sn2S6 ・2 C6H15N2 (2), crystallizes in the triclinic space group P¯1 with a = 7.3019(6), b = 11.1798(9), c = 13.2837(11) Å , α = 76.877(10), β = 74.719(9), γ = 82.972(10)°, Z = 1. Both structures feature [Sn2S6]4− anions acting as bidentate ligands and joining the octahedrally coordinated Mn2+ cations, but in 1 a molecular complex is formed, whereas in 2 a one-dimensional coordination polymer is observed. In 1 the Mn2+ cation has bonds to four N atoms of two 1,2-dach ligands, to one H2O molecule, and to one S atom of the [Sn2S6]4− anion. The [Sn2S6]4− anion is located on a center of inversion joining two symmetry related complexes. In 2 Mn2+ is surrounded by four N atoms of two 1,2-dach ligands and by two S atoms of two neighboring [Sn2S6]4− anions. In contrast to 1 a negatively charged coordination polymer is formed with [Sn2S6]4− anions acting as linkers and the Mn2+ centered complexes being the nodes. The co-crystallized 1,2-dach molecules are protonated, and they are located between the chains. The first compound was obtained from diluted aqueous solutions of 1,2-dach, and 2 crystallized from solutions containing < 25% H2O. In both compounds several short S···H distances indicate weak hydrogen bonding interactions. Compound 1 is stable up to 121 °C and 2 up to 220 °C. In the Raman spectra of 1 and 2 resonances which are typical for [Sn2S6]4− units could be observed. The band gaps are found to be 2.6 eV (477 nm) and 3.1 eV (400 nm) for 1 and 2, respectively.

The new tetraalkylammonium tetrathiomolybdates (Me4N)2[MoS4] (1) and (nBu4N)2[MoS4] (2) were prepared via a direct salt substitution using (NH4)2[MoS4] as starting material. Compound 1 crystallises in the non-centrosymmetric orthorhombic space group P212121 with a = 8.9233(4), b = 15.5210(9) and c = 37.255(3) Å. Compound 2 crystallises in the orthorhombic space group Fdd2 with a = 28.9142(18), b = 35.7811(10) and c = 15.6774(17) Å. The structures of both compounds consist of slightly distorted [MoS4]2− tetrahedra and tetraalkylammonium cations which are packed in different ways. Single crystals of (Et4N)2[MoS4] (3) were also investigated giving the lattice parameters a = 14.0346(7) and c = 12.5143(8) Å. A very strong disorder prevented a successful structure refinement and only the anion and one cation could be located. It is remarkable that the disorder of parts of the alkyl groups decreases with increasing chain length, in correlation with the IR and Raman vibrations of the [MoS4]2− tetrahedron showing a slight shift to lower energy with increasing alkyl chain length. The most prominent IR band of [MoS4]2− is broad but not split, indicating that the distortion of the tetrahedra is small.

The three new tetraalkylammonium tetrathiotungstates ((Me)4N)2[WS4] (1), ((Et)4N)2[WS4] (2) and ((nPr)4N)2[WS4] (3) were prepared via a direct salt substitution using (NH4)2[WS4] as starting material. Compound 1 crystallises in the chiral orthorhombic space group P212121 with a = 8.9433(4), b = 15.5658(9) and c = 37.279(2) Å . Compound 2 crystallises in space group P21/n with lattice parameters a = 16.6695(12), b = 9.3415(6), c = 16.9965(13) Å and β = 117.185(15)°. The third compound 3 crystallises in space group C2/c with the lattice parameters a = 32.440(2), b = 13.8453(6), c = 15.0563(10) Å and β = 109.19(7)°. The structures of all compounds consist of slightly distorted [WS4]2− tetrahedra and tetraalkylammonium cations which are packed in different ways. One interesting observation is that the disorder of parts of the alkyl groups decreases with increasing chain length. The IR and Raman spectra show the vibrations of the [WS4]2− tetrahedron with a slight shift with increasing alkyl chain length. The most prominent IR-band of the [WS4]2− tetrahedra is broad but not split, indicating that the distortion of the tetrahedra is small.

The new thioantimonate(III) (C6N2H18)Sb4S7 (C6N2H16 = 1,6-diaminohexane) was synthesized under solvothermal conditions using Sb, S and 1,6-diaminohexane (1,6-DAH). The compound crystallizes as orange needles in the triclinic space group P1̅ with lattice parameters a = 6.9834(5), b = 11.8748(10), c = 13.6588(12) Å , α = 115.248(9), β = 100.165(9) and γ = 92.568(9)°. A central SbS4 group shares edges with two other SbS4 moieties forming Sb3S8 units which are joined by SbS3 pyramids sharing vertices to form a chain of alternating Sb3S8 and SbS3 units. One S atom of the SbS3 pyramid connects neighboring chains into sheets which contain large Sb10S10 heterorings. The sheets are then further connected into four atoms thick double sheets. Six edge-linked SbS4 units are condensed yielding a complex Sb6S14 building block. Layers of diprotonated amines and thioantimonate( III) layers are stacked along [001] in a sandwich-like fashion with an interlayer distance of 8.46 Å . The amine layer is two molecules thick with the amines being oriented parallel to the anionic layers. The title compound represents the first example for a layered [Sb4S7]2− anion with a diamine as structure director. The compound is an optical semiconductor with a band-gap of about 1.9 eV

The new thioantimonate(III) [C6H17N3][Sb10S16] (C6H17N3 = 2-piperazine-N-ethylamine cation) was obtained under solvothermal conditions showing a unique anionic framework. The compound crystallizes in the monoclinic space group P21/c with four formula units in the unit cell. The lattice parameters are a=11.530(2), b=25.042(5), c = 13.709(3)Å, β =111.25(3)◦,V = 3689(2) Å3. The thioantimonate(III) anion is formed by interconnection of nine trigonal pyramidal SbS3 units and one SbS4 moiety. These primary building units share common corners and edges yielding Sb3S3 and Sb2S2 hetero-rings. Further condensation leads to strong undulated two atoms thick layers extending in the [010] direction, with a modulation period of about 14 Å. Very large Sb31S31 rings within the layers show a ‘double-ellipsoidal’ shape with approximate dimensions of 8.9 ・ 9.3 Å. The cations are located at the inflexion points of the layers and act as pillars between successive layers. The layers are stacked onto each other in a way that channels parallel to [001] are formed accommodating the organic cations. A remarkable observation is that the 2-piperazine-N-ethylamine cation is formed by cyclization of tren molecules (tren = tris(2-aminoethyl)amine) under in-situ conditions.

The new compounds Rb2CuTaS4 (1), Rb2CuTaSe4 (2), RbCu2TaSe4 (3), K3Ag3Ta2Se8 (4), and Rb3AgTa2Se12 (5) have been synthesized by the reactive flux method at 773 or 873 K. Their crystal structures were determined by single crystal X-ray diffraction. Crystal data for 1: space group Fddd, a = 5.598(1), b = 13.512(4), c = 23.854(5) Å , Z = 8; Crystal data for 2: space group Fddd, a = 5.782(1), b = 13.924(3), c = 24.653(5) Å , Z = 8; Crystal data for 3: space group C2cm, a = 5.7218(3), b = 19.2463(13), c = 7.7456(5) Å , Z = 4; Crystal data for 4: space group C2/c, a = 25.1374(19), b = 6.1007(3), c = 14.4030(11) Å , β = 119.703(8)◦, Z = 4; Crystal data for 5: space group P21/n, a = 9.8186(6), b = 13.7462(11), c = 15.7368(9) Å , β = 96.681(7)◦, Z = 4. The compounds 1 and 2 are built up of 1 ∞[CuTaQ4]2− anionic chains which are formed by edge-sharing CuQ4 and TaQ4 tetrahedra. The rubidium cations are located between the chains. Compound 3 consists of 2 ∞[Cu2TaSe4]− anionic layers separated by rubidium cations. The anionic layers are formed by1 ∞[CuTaSe4]2− chains which are connected by CuSe4 tetrahedra that share common edges with the TaSe4 tetrahedra of neighboring chains. In compound 4 1 ∞[Ag3Ta2Se8]3− anionic chains are found which are separated by potassium cations. These chains are formed by successive corner sharing of AgSe4 tetrahedra and edge sharing between AgSe4 and TaSe4 tetrahedra. All three structures are closely related with the sulvanite (Cu3VS4) structure type. Compound 5 contains a one dimensional 1 ∞[AgTa2Se12]3− anionic chain formed by interconnection of AgSe4 tetrahedra and [Ta2Se11] units. In the structure three monoselenide, three diselenide, and one triselenide anions are found. Raman and far-IR spectroscopic data of compounds 1 and 4 were collected and an interpretation is presented.

The solvothermal reaction of MnCl2·4 H2O, K2Se3 and Se in trans-cyclohexane-1,2-diamine (chxn) at 433 K yields dark blue crystals of [Mn(chxn)3]Se6 (1), and the reaction of MnCl2 ・4 H2O, K2Se3 and Te under similar conditions gives dark blue crystals of [Mn(chxn)3]2[H2chxn](TeSe2)2Se (2). While compound (1) crystallises in the orthorhombic space group Pbcn with the lattice parameters a = 13.7017(9), b = 19.9073(8) and c = 10.8058(5)Å , compound (2) crystallises in the monoclinic space group P21 with the lattice parameters a = 9.4396(6), b = 24.2450(2), c = 12.8170(8) Å and β =91.6(1)◦. In both structures discrete complex cations and polychalcogenide anions are found. In (1) the Se6 2− anions form a pseudo-layer arrangement with nearly rectangular pores. The complex cations are encapsulated by the arrangement of the Se6 2− anions. Some short distances between the amino groups of the ligands and the anions indicate weak hydrogen bonding. In compound (2) two independent [Mn(chxn)3]2+ and one unique H2chxn dications, two unique TeSe2 2− as well as one Se2− dianion coexist. The two complex cations exhibit different conformations. One of the two TeSe2 2− anions has the di-protonated chxn molecule in the neighbourhood and short Se···H separations indicate weak hydrogen bonding. The isolated Se2− ion is located above the ring of the di-protonated trans-cyclohexane-1,2-diamine molecule and again a short Se···H separation may be due to a weak hydrogen bond. Compound (1) decomposes in a single step when heated in an Ar atmosphere. In contrast, the thermal decomposition of compound (2) is complex and at least five different steps can be identified.

The non-stoichiometric chromium selenide Cr5.095(5)Se8 was prepared under high-pressure hightemperature conditions. The structure was refined from X-ray powder data with the Rietveld method in the non-conventional monoclinic space group F2/m, a = 12.2992(2), b = 7.12753(12), c = 11.4486(2) Å , β = 90.927(1)° and V = 1003.49(3) Å3. Three of the four unique Cr sites are fully occupied, and one site is only partially occupied. The structure may be viewed as being composed of alternating full and metal deficient layers which are oriented perpendicular to the crystallographic c axis of the pseudo-hexagonal unit cell. All Cr atoms are in an octahedral environment of six Se atoms. The CrSe6 octahedra of neighbouring layers share common faces whereas the octahedra with layers are joined by common edges. As a result short Cr-Cr distances of 2.867(3) and 2.951(6) Å are found across common faces while Cr-Cr separations between CrSe6 octahedra sharing edges are significantly longer. From a formal point of view charge balance requires a formulation as Cr4+ 0.715Cr3+ 4.38Se8. On the basis of the distortion of the CrSe6 octahedra the Cr4+ ions are mostly located on two different sites.

Treatment of germanium dioxide with a 33% aqueous solution of 1,2-diaminopropane (DAP) under solvothermal conditions leads to the formation of colourless octahedral crystals of the novel germanate (1,2-DAPH2)2Ge9(OH)4O18 · 2 H2O. The compound crystallises in the orthorhombic space group Pbca, a = 14.4155(10), b = 12.9384(9), c = 14.5417(8) Å,V =2712.2 (3) Å3; Z =4. The structure consists of an anionic [Ge9(OH)4O18]4− framework with isolated [1,2-DAPH2]2+ cations and water molecules in the channels of the structure. The primary building units of the anionic framework are GeO4 tetrahedra, GeO5 trigonal bipyramids, and GeO6 octahedra. The asymmetric unit consists of two GeO5 units sharing a common edge to form a Ge2O8 unit. This Ge2O8 unit is corner-linked to two GeO4 tetrahedra, and finally one GeO4 tetrahedron is connected to a GeO6 octahedron by cornersharing. The connectivity yields a chain-like Ge5O19 fragment as a secondary building unit (SBU). The chain fragments are interconnected with each other forming the three-dimensional framework. Three types of channels with diameters ranging from 5.98 to 8.025 Å intersect the three-dimensional germanate network. Upon heating the compound decomposes in three steps starting at about 125˚C losing the water and the 1,2-diaminopropane molecules. In situ X-ray diffraction experiments show that the water molecules are removed retaining the integrity of the skeleton of the material. The removal of H2O is accompanied with an anisotropic shrinkage of the structure. The original lattice parameters were obtained after the uptake of water.

The reactions of potassium polysulfides with elemental Nb were investigated with different analytical techniques. The amount of the polysulfide applied has no influence onto product formation, i. e. the ratio K2Sx: Nb is not important. The length of the polsysulfide chain, i. e. the value of x in K2Sx determines what product is formed. In sulfur-poor melts, K3NbS4 is observed. Increasing x to 5 - 6, K4Nb2S11 is formed with a structure containing S2 2− anions. Finally, applying a melt with x > 6, K6Nb4S25 is found as the product with a crystal structure containing the S5 2− polysulfide anion. When K2Sx (x < 5) is heated with sulfur in the first step the pentasulfide K2S5 is formed. Immediately after melting of K2S5 a reaction with elemental Nb occurs. The results of FT-IR and X-ray investigations have demonstrated that after oxidation the anion [Nb2S11]4− is formed relatively fast, and after a short time crystalline K4Nb2S11 can be detected. After 24 h the reaction is complete.

Two non-stoichiometric chromium rich Cr5+ x S8 (x = 0.20 and 0.26) samples were prepared under high pressure and high temperature conditions. In the crystal structures three different metal atom sites are fully and the fourth site is only partially occupied. The results of single crystal and Rietveld refinements are in good agreement. The CrS6 octahedra share common corners and common faces. Across common faces extraordinary short Cr—Cr distances are observed suggesting metal-to-metal bonding. On the basis of the distortion of the CrS6 octahedra Cr4+ is located on two of the four Cr sites. With increasing Cr content the amount of Cr4+ is lowered and the distortion of two of the four CrS6 octahedra is significantly reduced.

A new transition metal thioantimonate(III) with composition Mn2(H2N(CH2)2NH2)Sb2S5 has been synthesised under solvothermal conditions. Two trigonal SbSb3 pyramids and two octahedrally coordinated Mn atoms are interconnected to form Mn2SbS4 heterocubanes as secondary building units (SBU’s). The SBU’s are covalently linked into linear infinite onedimensional rods. Long Sb-S bonds connect the rods to form layers. The two N atoms of the ethylenediamine molecule (en) are chelating one Mn(II) ion. The amino hydrogen atoms of the en ligand are engaged in hydrogen bonding which is responsible for the different structure pattern of the title compound compared to a previously reported series of Mn-amino-thioantimonates(III) with analogous stoichiometry built up from different amino ligands.

The new compounds Ni2(tren)3(MO₂O2S6)2 · 2.75 H2O (I) and CO₂(tren)3(MoS4)2 (II) (tren = tris(2-aminoethyl)amine) were prepared under solvothermal conditions. The structure of I is built up of one-dimensional [Ni2(tren)3]n 4+ chains and isolated [MO₂O2S6]2-anions. Each Ni atom in the cationic chain is surrounded by six N-atoms to form a distorted octahedron. The connection of the Ni-atoms in the [Ni2(tren)3]n 4+ -units with the tren molecules leads to zigzag chains in the (100) plane. The situation is different for compound II which consists of isolated [CO₂(tren)3]4+ cations and discrete tetrahedral [MOS4]2-anions. The Co atom in the cation is in a distorted trigonal bipyramidal environment of four N atoms of one tren molecule and of one N atom from a bridging tren-molecule, building up the dimeric structure of the [CO₂(tren)3]4+ unit. Between the anions and cations of both compounds hydrogen bonding is observed. The thermal behaviour of I and II was investigated using differential thermoanalysis and thermogravimetry. On heating I first looses the crystal water and then decomposes slowly in one step, whereas II decomposes also in one step, but at a significantly lower temperature.

Thioantimonates, Solvothermal Synthesis, Chalcogenides The reaction of elemental manganese, antimony and sulfur with ethylamine under mild solvothermal conditions yielded a thioantimonate(III) with composition Mn2(EA)2Sb2S5 (EA = C2H5NH2) that is a new member of a series of polymeric manganese thioantimo-nates(III). The structure of the title compound consists of layers of a neutral mesh-like Mn2Sb2S5 framework. The ethylamino ligands coordinated to the Mn centres separate the sheets and fill the voids within the layers formed by the interconnection of Mn2Sb2S4 hetero-cubane like building blocks. Below 273 K a reversible phase transition occurs, which is accom­panied by a doubling of the crystallographic a-axis.

The reaction of manganese(II)-chloride-tetrahydrate, caesium triselenide and elemental selenium or tellurium in 1,2-ethanediamine (en) under solvothermal conditions leads to the formation of two new isostructural compounds [Mn(en)3]Se3 (1) and [Mn(en)3]TeSe2 (2). The compounds crystallize in the orthorhombic space group Pbcn with the lattice parameters a = 1149.39(9), b = 1506.83(11), c = 935.96(6) pm for 1 and a = 1184.1(2), b = 1495.3(2), c = 949.8(1) pm for 2. Their crystal structures are built up of [Mn(en)3]2+ cations and Se3 2- or TeSe2 2- anions, respectively. Each cation is surrounded by six next neighbouring anions, and vice versa. Between the cations and the anions hydrogen bonding is observed. The thermal behaviour was investigated using differential thermal analysis, thermogravimetry as well as X-ray powder diffraction. Completely different properties were found. Compound 1 decomposes in two distinct endothermic steps, while compound 2 shows only one endothermic peak. The weight loss for 1 corresponds roughly to the emission of all en molecules, whereas the weight loss for 2 is significantly lower. The final products are composed of MnSe2 and elemental Se or Te, respectively, and an unknown crystalline phase which is different for the two samples

The new ternary one-dimensional chain compounds K2ZrS4 , Rb2ZrS4 and Rb2HfS4 were prepared at 350 °C by reacting A2S3 and S with elemental M (A = K, Rb; M = Zr, Hf). They are isostructural, crystallizing in the orthorhombic space group Pbca with Z = 8 . The M atoms are in a distorted octahedral environment of four S2− anions and one S2 2− unit. The structure consists of infinite anionic chains comprised of edge-sharing M S6 octahedra running parallel to the [001] direction separated by the alkali metal cations. The composition of the chain may be formulated as 1 ∞[MS4/ 2 (S2)2−]. The two crystallographically independent alkali cations are in eight-and ninefold coordination of S atoms.

(CH3NH3)2Sb2S4 has been isolated from the reaction of antimony with sulfur in the presence of manganese in an ethanolic solution of methylamine under solvothermal conditions. Two pyramidal SbS3 units are linked via common S-S edges to give dimeric Sb2S4 2- anions, which are joined via secondary Sb···S contacts of 3.074(2) and 2.975(2) Å forming infinite 1 ∞ [SbS2]-2n chains consisting of edge-linked ψ-SbS4 trigonal bipyramids. The cis configuration of the Sb2S4 2- anions in the title compound is observed for the first time. A specific hydrogenbonding pattern between the amino-hydrogen and the sulfur atoms stabilizes this configuration and gives rise to anionic layers separated by the methyl groups.

The title compound has been synthesized under solvothermal conditions by the reaction of elemental chromium, antimony and selenium in a solution of 40% 1,2-ethanediamine (en) in methanol. The crystal structure consists of tetrahedral SbSe4 3- anions which are connected by monoprotonated 1,2-ethanediamine (enH+) cations via N-H--Se hydrogen bonding. The enH+ cations are joined via strong N-H -N hydrogen bonds between the ammonium hydrogen and the amino nitrogen atom forming four distinct chains, each built up of three crystallographically independent enH+ cations. Two of these chains are running parallel to [100], the other two are parallel to [010]. Based on this arrangement different centrosymmetric or non-centrosymmetric hydrogen bonding patterns are possible, but only in one chain the sequence of NH2 and NH3 + groups was determined by X-ray diffraction

The reaction of manganese with antimony and sulfur in an aqueous ethylenediamine (en) solution under hydrothermal conditions gives Mn(en)3Sb4S7. The structure of the title compound consists of Mn(en)3 2+ cations and infinite one-dimensional (Sb4S7 2-)„ anions forming slabs via long secondary interchain Sb···S bonds. A comparison between phases with polymeric (Sb4S7 2- )„ anions shows in general a trend towards a lower dimensionality of the thioantimonate assembly with increasing cation size. In the title compound the lowest number of interchain Sb···S interactions is observed among other phases with chainlike Sb4S7 2- anions.

Chelate complexes of 1,2-dimesitoylbenzene radical anion with alkali metal cations exhibit in aprotic solution extremely large ESR /ENDOR metal coupling constants. For rationalization, structures of both the neutral molecule (H3C)3H2C6 - CO - C6H4 - CO - C6H2(CH3)3, in which the two carbonyl groups are twisted out of the benzene ring plane by dihedral angles of ± 3̄7̄°, and a sodium contact ion quadruple have been determined. One of the dimers [dimesitoylbenzeneH⊖ (Na⊕H2N H2C - CH2NH2)]2, although generated by Na metal mirror reduction of 1,2-dimesitoylbenzene in aprotic DME solution with added ethylendiamine for better electron transfer, surprisingly contains two 245 pm short (!) hydrogen bridges ⊖O ··· (H)O and in addition two solvation bridges e ⊖O ··· Na⊕(H2NH2C - CH2NH2) ··· O⊖. Results of MNDO calculations based on the experimental coordinates support the proposed concept.

Source of material: Arsenic oxide, sulfur, manganese and tetraphenylphosphoniumbromide (molar ratio: 1:5:1:1 ) in 5 ml of 2m ammonia solution were reacted in teflon coated steal autoclaves at 398 К for 6 days. The product was filtered off and washed with deionized water. The structure of the title compound is built up of well-separated Ph4P' -cations and [As4S6]^~-anions. The tetraphenylphosphonium cations form pairs with sixtuple embracements of the phenyl rings with the midpoint located on a centre of inversion and relatively short Ρ···Ρ distances of 6.331(3) Â and 6.351(3) Â. These pairs are arranged in corrugated sheets parallel to ((Ю1) with a honey-comb like arrangement of the Ρ atoms, a pattern which is found in many compounds containing tetraphenylphosphonium cations. The [As4S6]^~-anion forming a bicyclic ring system of alternating As and S atoms consists of two five-membered rings with the two common arsenium centers As3 and As4. The structure of the [As4S6]^"-anion is related to that of AS4S4 (see ref. 1 ) by replacement of an As-As bond by two As-S~ units. The As3-As4 bond length of 2.621(2) Â is significantly longer than that in elemental As by about 0.12 Â. The other two arsenium atoms Asl and As2 are each bound to an additional exocyclic sulfur atom. All arsenium atoms have trigonal pyramidal coordination with sums of angles around Asl and As2 of 3(Ю.7(9)° and 298.4(9)° and around As3 and As4 of 308.1(8)° and 307.2(8)°. The As-S bond lengths to As3 and As4 are shorter than those to Asl and As2 by about 0.1 Â. The longer As-S distances as well as the stronger pyramidalization of Asl and As2 suggest that the negative charge is predominantely located on these centers. It is noted that the geometrical parameters of the [As4S6]^~-anion are comparable to those in piperidinium hexathiotetraarsenate (see ref. 2). C48H40AS4P2S6, orthorhombic, Pbca (No. 61), α =11.1998(6) Â, b =19.657(1) Â, с =44.177(5) Â, V=9725.5 Â^Z=8,R{F) =0.050, A w f f ^ ) = 0 . 1 1 6 .

Lattice constants at 100 K are: a=6.698, b=13.142, c=20.668 A, β=96.77 °, R=0.0193 and space group C2/c.

CsPPbS4, orthorhombic, Pnma (no. 62), a = 18.185(1) angstrom b = 6.8085(5) angstrom, c = 6.3518(5) angstrom, V = 786.4 angstrom(3), Z = 4, R-gt(F) = 0.039, wR(ref)(F-2) = 0.101, T = 293 K.