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In this paper, we report on a non-oxidative topochemical route for the synthesis of a novel indate-based oxyfluoride, LaBaInO3F2 using a low-temperature reaction of Ruddlesden-Popper-type LaBaInO4 with polyvinylidene difluoride as a fluorinating agent. The reaction involves the insertion and substitution of oxide ions by fluoride ions. From the characterization via powder X-ray diffraction and Rietveld analysis as well as attenuated electron diffraction tomography it could be followed that the fluorination results in a symmetry lowering from I4/mmm (139) to monoclinic C2/c (15) with an expansion perpendicular to the perovskite layers and a strong tilting of the octahedra along the ab plane. While an ordering of vacancies on the interstitial sites is observed, disorder of anions on the three anion sites seems be favored. The most stable configuration for the anion ordering is estimated based on an evaluation of bond distances from ADT measurements via bond valence sums. The observed disordering of the anions in the oxyfluoride consequently resulted in changes of the bandgap, interestingly leading to an enhanced photocatalytic activity for the hydrogen (H2) evolution as compared to the pure oxide. Thus, we show that topochemical anion modification can present a viable route to obtain improved photocatalysts.

The complete series of sodium rare-earth metal(III) chloride oxotellurates(IV) with the composition Na2 RE 3Cl3[TeO3]4 (RE = Y, La–Nd, Sm–Lu) has been synthesized via solid-state reactions. For these conversions mixtures of the respective rare-earth metal(III) oxides, tellurium dioxide and sodium chloride as flux and reactant were prepared, intimately ground and heated for 5 days at 1225 K. The almost colorless single crystals were characterized via single-crystal X-ray diffractometry. In the monoclinic crystal structure of these compounds two crystallographically different rare-earth metal(III), but only one sodium cation sites occur. [REO8]13− polyhedra around both RE 3+ positions as well as sodium-centered polyhedra [NaO4Cl4]8− form layers via different connectivity modes. These layers spread out parallel to the (001) plane and arrange alternatingly resulting in the three-dimensional network of the Na2 RE 3Cl3[TeO3]4 structure, where the Te4+ lone-pair cations at two different sites work as linkers by forming isolated ψ 1-tetrahedra [TeO3]2−. Some of these compounds were represented before in different settings of space group C2/c. Now the complete series of the Na2 RE 3Cl3[TeO3]4 representatives with RE = Y, La–Nd, Sm–Lu is described consistently for a better comparison and understanding. Additionally, a single crystal of Na2Pr3Cl3[TeO3]4 was measured via energy dispersive X-ray analysis to verify the included elements, powder samples of Na2Nd3Cl3[TeO3]4 were characterized by X-ray diffractometer data for a phase-purity check and a single-crystal Raman spectrum of Na2Yb3Cl3[TeO3]4 served for proving the signature of discrete [TeO3]2− anions.

Lithium yttrium(III) oxidotungstate(VI), LiY5W8O32, was synthesized by solid-state reaction of a mixture of lithium chloride, yttrium sesquioxide, and tungsten trioxide. It crystallizes monoclinically in space group C2/c (a = 1908.34(5) pm, b = 561.80(1) pm, c = 1147.22(3) pm, β = 111.255(2)°, Z = 2). The structure comprises one mixed Li+/Y3+ cationic position (molar ratio Li:Y1 = 1:1) and one cationic position exclusively occupied by Y3+ cations. All W6+ cations are surrounded by six O2– anions, forming distorted octahedral coordination polyhedra, which are mutually linked by both edges and vertices to cascaded 2∞{[W4O16]8–} layers. Lithium yttrium(III) oxidosilicate(IV) oxidotungstate(VI), LiY5[SiO4]2[WO4]4, was obtained as by-product in the synthesis of YF[WO4] by sintering a mixture of Y2O3, YF3, and WO3 with lithium chloride as fluxing agent in sealed silica ampoules. It crystallizes orthorhombically in space group Pban ( a = 512.08(4) pm, b = 1673.35(12) pm, c = 493.68(4) pm, Z = 1) bearing one mixed crystallographic position occupied by Li+ and Y3+ cations in a molar ratio of 1:3 and one exclusive Y3+ position in its structure. The coordination polyhedra around the Si4+ and W6+ cations are isolated tetrahedra built up by four O2– anions each. The crystal structure of this silicate tungstate can be derived from the scheelite-type structure by inserting anionic 2∞{(Y2[SiO4])–} layers between cationic 2∞{[(Li/Y1)2[WO4]2]+} double layers.

Single-crystal x-ray diffraction refinements indicate $\mathrm{SrS}{\mathrm{n}}_{2}\mathrm{F}{\mathrm{e}}_{4}{\mathrm{O}}_{11}$ crystallizes in the hexagonal $R$-type ferrite structure with noncentrosymmetric space group $P{6}_{3}mc$ and lattice parameters $a=5.9541(2)\phantom{\rule{0.16em}{0ex}}\AA{}, c=13.5761(5)\phantom{\rule{0.16em}{0ex}}\AA{}, Z=2$ ($R(F)=0.034$). Octahedrally coordinated $2a$ [$M$(1) and $M$(1a)] and $6c$ sites $[M(2)]$ have random, mixed occupation by Sn and Fe; whereas the tetrahedrally coordinated $2b$ sites [Fe(3) and Fe(3a)] are exclusively occupied by Fe, whose displacement from the ideal position with trigonal-bipyramidal coordination causes the loss of inversion symmetry. Our dc and ac magnetization data indicate $\mathrm{SrS}{\mathrm{n}}_{2}\mathrm{F}{\mathrm{e}}_{4}{\mathrm{O}}_{11}$ single crystals undergo a ferro- or ferri-magnetic transition below a temperature ${T}_{C}=630\phantom{\rule{0.16em}{0ex}}\mathrm{K}$ with very low coercive fields ${\ensuremath{\mu}}_{\mathrm{o}}{H}_{c\ensuremath{\perp}}=0.27\phantom{\rule{0.16em}{0ex}}\mathrm{Oe}$ and ${\ensuremath{\mu}}_{\mathrm{o}}{H}_{c\ensuremath{\parallel}}=1.5\phantom{\rule{0.16em}{0ex}}\mathrm{Oe}$ at 300 K, for applied field perpendicular and parallel to the $\mathbit{c}$ axis, respectively. The value for ${T}_{C}$ is exceptionally high, and the coercive fields exceptionally low, among the known R-type ferrites. Time-dependent dc magnetization and frequency-dependent ac magnetization data indicate the onset of short-range, spin-glass freezing below ${T}_{f}=35.8\phantom{\rule{0.16em}{0ex}}\mathrm{K}$, which results from crystallographic disorder of magnetic $\mathrm{F}{\mathrm{e}}^{3+}$ and nonmagnetic $\mathrm{S}{\mathrm{n}}^{4+}$ ions on a frustrated Kagome sublattice. Anomalous ac susceptibility and thermomagnetic relaxation behavior in the short-range-ordered state differs from that of conventional spin glasses. Optical measurements in the ultraviolet to visible frequency range in a diffuse reflectance geometry indicate an overall optical band gap of 0.8 eV, consistent with observed semiconducting properties.

Two new non-isostructural lanthanide(III) nitride tellurides with the composition M4N2Te3 bearing terbium (Tb4N2Te3) and dysprosium (Dy4N2Te3) could be synthesized by the reaction of terbium (Tb) or dysprosium (Dy) metal with sodium azide (NaN3), tellurium (Te), iodine (I2), and sodium iodide (NaI) as flux in evacuated silica tubes for seven days at 950 °C. Tb4N2Te3 crystallizes orthorhombically in space group Pnna with the lattice parameters a = 727.14(5), b = 1164.37(8), c = 1100.93(7) pm, Vm = 140.33(2) cm3·mol–1 (Z = 4). In contrast, Dy4N2Te3 appears in the monoclinic space group P21/n with the lattice parameters a = 719.56(5), b = 1164.05(8), c = 1097.34(7) pm, β = 91.327(3)°, Vm = 138.34(2) cm3·mol–1 (Z = 4). Corresponding to the lanthanide contraction the cell parameters of Dy4N2Te3 show slightly smaller values compared to Tb4N2Te3, but the change of symmetry leads to a different crystal system. Symmetry operations related to a and c are lost according to P2/n21/n2/a P121/n1 and the two crystallographically independent M3+ cations in Tb4N2Te3 split into four in Dy4N2Te3. Both Tb3+ cations are coordinated by six anions in first sphere plus one Te2– anion further apart for (Tb1)3+ leading to capped trigonal prisms and distorted octahedra. The four Dy3+ cations with coordination numbers of six plus one and three times six also reside in capped and uncapped distorted octahedral anionic coordination. Both crystal structures have infinite zigzag chains in 1∞{[NM]3+} in common, which are formed by trans-edge connected [NM4]9+ tetrahedra. They run along [010] and exhibit two crystallographically different N3– anions in both cases. The latter are coordinated on the one hand to two sorts of Tb3+ cations in Tb4N2Te3 and on the other hand to four sorts of Dy3+ cations in Dy4N2Te3 as major structural difference. However, both crystal structures show a clear group-subgroup relationship.

The complex cations [Cu(dippf)(DML)]+ ([1]+) and [Cu(dppf)(DML)]+ ([2]+), where dippf = 1,1′-bis(diisopropylphosphino)ferrocene, dppf = 1,1′-bis(diphenylphosphino)ferrocene, and DML = 1,3-dimethyllumazine, were prepared and crystallized as BF4– or PF6– salts. Structure determinations of the tetrafluoroborates revealed asymmetric O4,N5 chelation of DML to copper(I) with longer Cu–O bonds of about 2.25 A. Reversible oxidation to [1]2+ and [2]2+ proceeds at the ferrocene units, while reduction leads to the neutral radical complexes [1] and [2] with the unpaired electron localized on the DML ligand. The occurrence of two voltammetric steps for the one-electron-reduction process is attributed to a two-species equilibrium caused by the hemilabile coordination of DML. Electrochemical and spectroelectrochemical measurements (UV–vis, IR) reveal increased coordination lability of the reduced complexes and their slow fragmentation.

Solid-state reactions of La2O3, LaBr3, and MoO3 in molar ratios of 1:1:3 lead to single crystals of LaBrMoO4 among a few by-products, which emerge from redox reactions of Br– with hexavalent molybdenum. To obtain the analogous cerium compound, Ce2O3 was synthesized in situ by using CeO2 and Ce in a 3:1 molar ratio. The two rare-earth metal bromide ortho-oxidomolybdates(VI) REBrMoO4 (RE = La and Ce) crystallize isotypically in the monoclinic space group Pc (a = 982 – 977 pm, b ≈ 581 pm, c = 810 – 803 pm, β ≈ 90°, Z = 4). In the crystal structure, two crystallographically unique RE3+ cations are present, both with similar coordination environments of three plus one Br– and six O2– anions in the shape of distorted tetracapped trigonal prisms. The two distinguishable Br– anions both display coordination spheres of three plus one RE3+ cations each, building up distorted tetrahedra. These are fused together via four common edges to form anti-PbO-type 2∞{[BrRE]2+} layers (e = edge-connecting) parallel to the (100) plane. Two crystallographically different oxidomolybdate(VI) units are also found in the structure, which can be best described as strands of apically vertex-shared [MoO5]4– trigonal bipyramids along [001] represented by the formula 1∞{[MoOO]2–} (v = vertex-connecting, t = terminal). The aforementioned 2∞{[BrRE]2+} layers and the 1∞ {[MoOO]2–} chains are alternately stacked along the a axis. The peculiarity of this structure is expressed by the position of the Mo6+ cations, which are not situated in the center of the bipyramids, but reside offset in a trigonal pyramid. Since both the (Mo1)6+ and the (Mo2)6+ cations are located in the same partial tetrahedron, relative to the triangular plane of the trigonal bipyramid, a structure description in a non-centrosymmetric space group is immanent. Both title compounds display a twinned crystal structure with strong similarities to those of the chloride homologues REClMoO4 (RE = La – Pr) and LaClWO4.

The Cu(I)-catalyzed reaction of 1-bromo-2-iodobenzenes and other 1,2-dihalobenzenes with 1,3-cyclohexanediones in DMF at 130 °C using Cs(2)CO(3) as a base and pivalic acid as an additive selectively delivers 3,4-dihydrodibenzo[b,d]furan-1(2H)-ones with yields ranging from 47 to 83%. The highly regioselective domino process is based on an intermolecular Ullmann-type C-arylation followed by an intramolecular Ullmann-type O-arylation. Substituted products are accessible by employing substituted 1-bromo-2-iodobenzenes and substituted 1,3-cyclohexanediones as substrates. Reaction with an acyclic 1,3-diketone yields the corresponding benzo[b]furan.

Single crystals of the novel compound BaZnRu5O11 were grown from a barium chloride flux. The composition was determined from refinements of single crystal X-ray diffraction data and microprobe analysis. BaZnRu5O11 crystallizes in a supercell of the R-type ferrite structure with doubled a and b unit cell parameters (space group P63/m, Z = 8, a = 11.7411(2) A, c = 13.6842(4) A). The reason for the superstructure is the formation of Ru–Ru pairs with short distances within the idealized kagome net extending in (001). No indication of Zn/Ru mixed occupied sites was observed. BaZnRu5O11 does not show any sign of magnetic ordering down to 1.8 K. A large negative Curie–Weiss temperature ΘW⊥ = −290 K (ΘW|| = −230 K) suggests strong Ru3+ (S = ½) antiferromagnetic interactions frustrated on the kagome network of this compound. It is suggested that distortion of the well-ordered kagome sublattice gives rise to unusual behaviour of magnetic and electrical transport properties at low temperatures: BaZnRu5O11 single crystals exhibit a susceptibility χ ∼ 1 − T and electrical resistivity ρ ∼ T1.6 below about 10 K which may indicate a non-Fermi liquid.

Crystals of the three novel oxorhutenates SrNiRu5O11 (a = 11.7374(2) Å, c = 13.2088(4) Å), SrZnRu5O11 (a = 11.7271(2) Å, c = 13.4246(4) Å), and Sr0.63(1)Ba0.37ZnRu5O11 (a = 11.7245(4) Å, 13.5268(4)) were obtained applying a flux-growth technique. A superstructure of the R-type ferrite crystal structure with doubled hexagonal a-axis (space group P63/m, Z = 8) originates from Ru—Ru pair formation within the kagome nets extending in (001). No indication for an intermixing of 3d metals at the Ru sites was observed.

Using the ‘Click Protocol’ the new ligands 1-(cyclohexyl)-4-(2-pyridyl)-1,2,3-triazole (1), 1-(2-trifluoromethyl phenyl)-4-(2-pyridyl)-1,2,3-triazole (2), 1-(4-hexyl phenyl)-4-(2-pyridyl)-1,2,3-triazole (3), 1-(2-mercaptomethyl phenyl)-4-(2-pyridyl)-1,2,3-triazole (4) and 1-(4-N,N-dimethylamino phenyl)-4-(2-pyridyl)-1,2,3-triazole (5) were prepared by reacting 2-ethynylpyridine with the corresponding azides. In the next step the ligands were reacted with suitable palladium and platinum precursors to yield the cis-dichloro-palladium complexes 1a–4a and platinum complexes 1b–4b. Investigation of the molecular structure of the free ligands 1 and 5 reveals the formation of infinite chains in the 3D structure which are governed by hydrogen bonds between the triazole units. Likewise the 3D structure of 1a shows infinite chains which are held together by multiple remarkably short C–H⋯Cl–Pd contacts. Electrochemical investigation of the free ligands by cyclic voltammetry showed irreversible reduction processes at highly negative potential. Upon metal complexation huge anodic shifts of the reduction potential were observed. To further characterize the electronic properties of all the compounds UV–Vis spectra were also analyzed.

2-Diphenylphosphanyl-1,3,2-diazaphospholidines were prepared via metathesis from 2-chloro-1,3,2-diazaphospholidines and LiPPh2. For some of the products, symmetrisation to tetraphenyldiphosphane and 2,2′-bis-1,3,2-diazaphospholidinyls was observed. Most of the derivatives were characterised by single-crystal X-ray diffraction, which showed that all compounds studied feature elongated exocyclic P–Cl or P–P-bonds, respectively. The extent of this bond lengthening is in the P-phosphanyl-substituted species similar and in the P-chloro-derivatives less pronounced than in corresponding CC-unsaturated 1,3,2-diazaphospholenes. Structure correlation involving comparison of exocyclic P–X and endocyclic P–N distances suggests that n(N)/σ*(P–X) hyperconjugation contributes strongly to the bond lengthening and induces a perceptible weakening of the P–P bonds in 2-diphenylphosphanyl-1,3,2-diazaphospholidines, which should render these compounds interesting substrates for P–P bond activation reactions.

Using the noninnocent ligand Q [= 4,6-di-tert-butyl-(2-methylthiophenylimino)-o-benzoquinone] with a thioether group as potential coordination function, it has been possible to substantiate a single-electron transfer induced oxidative addition within the complex [IrCp*Q]0/+ (Cp* = C5Me5) via structural characterization (catecholato → semiquinonato transition coupled with reversible S→Ir coordination), via cyclic voltammetry, EPR, and DFT (semiquinone formulation with about 8% Ir participation). The intramolecular rearrangement of the 16-electron precursor [IrCp*Q] triggered by electron removal illuminates the complementary activities of the substrate binding metal and the electron-buffering ligand as was recently employed by Ringenberg et al. in dihydrogen activation (Organometallics2010, 29, 1956).

Reduction of an unsymmetrically substituted α-diimine followed by condensation with PCl3 yielded a P-chloro-N-aryl-N′-alkyl diazaphospholene which was further converted into an unsymmetrical diazaphospholium triflate by reaction with trimethylsilyl triflate. Reaction of tetramers of N-H- or N-alkyl-benzo-1,3,2-diazaphospholes with methyl triflate or triflic acid led in one step to triflate salts of unsymmetrically substituted benzo-1,3,2-diazaphospholium cations. Determination of the crystal structures of two of these derivatives by single-crystal X-ray diffraction studies revealed that individual cations and anions in the crystal lattice interact via specific electrostatic, π-stacking, or van-der-Waals type interactions to form supramolecular assemblies. Thermoanalytical measurements disclosed that benzo-diazaphospholium triflates with medium length alkyl chains melt below 100 °C and exhibit a strong tendency to form supercooled liquids.

Single-crystal x-ray diffraction refinements indicate SrSn2Fe4O11 crystallizes in the hexagonal R-type ferrite structure with non-centrosymmetric space group P63mc and lattice parameters a = 5.9541(2) Å, c = 13.5761(5) Å, Z = 2 (R(F) = 0.034). Octahedrally coordinated sites are randomly occupied by Sn and Fe; whereas tetrahedrally coordinated sites are exclusively occupied by Fe, whose displacement from ideal trigonal-bipyramidal coordination causes the loss of inversion symmetry. DC magnetization data indicate SrSn2Fe4O11 single crystals undergo ferro- or ferri-magnetic order below a transition temperature TC = 630 K with very low coercive fields Hc⊥ = 0.27 Oe and Hc// = 1.5 Oe at 300 K, for applied fields perpendicular and parallel to the c-axis, respectively. The value for TC is exceptionally high, and the coercive fields exceptionally low, among the known R-type ferrites. Enhanced coercivity and thermomagnetic hysteresis suggest the onset of short-range, spin glass order occurs below Tf = 35 K. Optical measurements indicate a band gap of 0.8 eV, consistent with wide-gap semiconducting behavior and a previously established empirical correlation between the semiconducting gap and TC for R-type ferrites based upon Ru.

La3FMo4O16 crystallizes in the triclinic crystal system with space group P1 ¯ [a = 724.86(2) pm, b = 742.26(2) pm, c = 1469.59(3) pm, α = 101.683(2)°, β = 102.118(2)°, γ = 100.279(2)°] with two formula units per unit cell. The three crystallographically independent La 3+ cations show a coordination number of nine each, with one F – and eight O 2– anions forming distorted monocapped square antiprisms. The fluoride anion is coordinated by all three lanthanum cations to form a nearly planar triangle. Besides three crystallographically independent tetrahedral [MoO4] 2– units, a fourth one with a higher coordination number (CN = 4 +1) can be found in the crystal structure, forming a dimeric entity with a for

The lanthanide chloride ortho-oxomolybdates LnCl[MoO4] (Ln = La, Ce, Pr) crystallize in the monoclinic space group P21/c(a = 1921–1906 pm, b ≈ 580 pm, c = 804–789 pm, β ≈ 90.04°, Z = 8).In the crystal structure, two crystallographically unique Ln3+ cations are present, both with the same coordination environment of four Cl– and six O2– anions in the shape of a distorted tetracapped trigonal prism. The two distinguishable Cl– anions both display a coordination sphere of three plus one Ln3+ cations, building up distorted tetrahedra. These are fused together via four common edges to form litharge-analogous layers (e = edge-connecting) parallel to the (100) plane. Two crystallographically different oxomolybdate units are also found in the structure, which can be best described as strandsof apically vertex-shared [MoO5]4– trigonal bipyramids of the formula (v = vertex-connecting, t = terminal) along [001]. These building blocks, the layers and the chains are alternately stacked along the a axis. The peculiarity of this structure is expressed by the position of the Mo6+ cations, which are not situated in the center of the bipyramids, but reside offset in their lower or upper trigonal pyramids (≈ tetrahedra). The Mo6+ cations with an x / a parameter between 0 and 0.5 can be found within the lower trigonal pyramids of those bipyramids (if viewed along the [001] direction), whereas those with 0.5 < x / a < 1 are located in the upper trigonal pyramid. Therefore, an alternating arrangement of the strands is observed. Due to the special constitution of the Ln3+ cations in distorted litharge-analogous layers, a special magnetic effect was assumed, but in phase-pure samples of e.g. CeCl[MoO4] mainly Curie–Weiss behavior could be detected.

The new chalcogenides CsCuNd2Se4 and CsCuGd2Te4 with analogous formulae were prepared from the elements by a flux method with CsCl as fluxing agent and cesium source. CsCuNd2Se4 crystallizes in the orthorhombic space group Cmcm (no. 63) with four formula units per unit cell (a = 424.69(3), b = 1475.81(8), c = 1465.42(8) pm), whereas CsCuGd2Te4 is monoclinic with the space group C2/m (no. 12) and twelve formula units per unit cell (a = 3764.75(19), b = 436.70(2), c = 2105.37(11) pm, β = 107.423(4)°). Both crystal structures feature three-dimensional arrangements of the lanthanide and coinage metal cations along with the chalcogenide anions according to {}^3_\infty{[CuLn2Ch4]–} (Ln = Nd or Gd, Ch = Se or Te), leaving channels behind, in which the Cs+ cations are incorporated. Hereby, vertex-linked [CuCh4]7– tetrahedra join to form {}^1_\infty{[CuCh3]5–} chains in both cases. Whereas for the CsCuNd2Se4 structure, these chains ({}^1_\infty{[CuSe3]5–}) are embedded into a three-dimensional network, erected by edge- and vertex-linked [NdSe6]9– octahedra, which form corrugated layers further connected by common edges, in CsCuGd2Te4 a different three-dimensional {}^3_\infty{[Gd2Te4]2–} framework arises, comprising {}^1_\infty{[CuTe3]5–} chains, as well as vertex- and edge-linked [GdTe6]9– octahedra. The major difference of the structures originates from the channels, in which the Cs+ cations are located. In the tunnels of CsCuNd2Se4, the Cs+ cations exhibit a bicapped trigonal prismatic selenide coordination, whereas in CsCuGd2Te4 with two Cs+ cations in one channel, they show bicapped trigonal prisms, as well as monocapped cubes of telluride anions as coordination spheres.

The structurally related oxide nitride chalcogenides Tb3ONSe2 and La5O2NS4 can be prepared by the oxidation of the respective lanthanoid metal (M = Tb and La) with selenium or sulfur and sodium azide (NaN3) in the presence of oxygen-containing impurities, when iodine (I2) or the corresponding lanthanoid trichloride (MCl3) is used as sodium trap for the formation of NaI or NaCl, respectively. The thermal treatment of these mixtures along with additional NaI or NaCl as flux at 900 °C in evacuated silica tubes yielded transparent, yellow polyhedra in the case of Tb3ONSe2 or orange, lath-shaped crystals of La5O2NS4. Both monoclinic structures (C2/m, Z = 4) were determined from X-ray single-crystal diffraction data (Tb3ONSe2: a = 1548.85(9), b = 392.02(2), c = 968.61(6) pm, β = 97.194(3)°; La5O2NS4: a = 1571.13(8), b = 409.67(2), c = 1681.03(9) pm, β = 101.204(3)°). The crystal structure of Tb3ONSe2 comprises three crystallographically different Tb3+ cations residing in six- and sevenfold coordination of the respective anions, whereas the crystal structure of La5O2NS4 shows five different La3+ cations with coordination numbers from six to eight. For the first time in the chemistry of oxide nitride chalcogenides of the lanthanides, an ordering of the light anions (O2– and N3–) is observed, and proper structure descriptions based on vertex- and edge-connected [OM4]10+ and [NM4]9+ tetrahedra (M = Tb and La) becomes possible. As main structural feature, a bulky chain {}^1_\infty{[ONTb3]4+} running along [010] can be detected in the crystal structure of Tb3ONSe2. The same morphology, but a different chemistry is realized in the related crystal structure of La5O2NS4, where these topologically equivalent strands {}^1_\infty{[O2La3]5+} and an additional second chain {}^1_\infty{[NLa2]3+}, built up by vertex- and edge connected [NLa4]9+ tetrahedra, compose the compound. As supporting tool for the distinction of the O2– and N3– anions in both crystal structures, the valence-bond concept is also applied.

The two new compounds Er3OFS3 and Er3OF3S2 vary mostly in their fluoride and sulfide content. The fluoride-poor erbium(III) oxide fluoride sulfide Er3OFS3 crystallizes in the tetragonal space group I4/mmm (a = 374.86(2), c = 2068.41(9) pm, Z = 2) with two crystallographically different Er3+ cations. (Er1)3+ is surrounded by six S2– anions in the shape of a slightly distorted octahedron, whereas (Er2)3+ exhibits a coordination number of eight (4 × O2–/F– and 4 × S2– arranged as a square antiprism). In the crystal structure of Er3OFS3 edge-sharing tetrahedral [ZEr4]10.5+ units (Zn– = 50 % O2– + 50 % F–) form condensed {}^2_\infty[OFEr2]3+ layers. These layers alternate with {}^2_\infty[ErS3]3– sheets, built up of [ErS6]9– octahedra, which are connected through four common edges, to complete the three-dimensional crystal structure of Er3OFS3. The fluoride-rich erbium(III) oxide fluoride sulfide Er3OF3S2 crystallizes in the orthorhombic space group Ccce (a = 538.31(2), b = 1892.03(9), c = 538.27(2) pm, Z = 4). Two crystallographically distinct Er3+ cations are present in its crystal structure. (Er1)3+ is surrounded by eight Zn– anions (Z = 25 % O2– + 75 % F–) in the shape of a twisted square antiprism, whereas (Er2)3+ holds a coordination number of nine (4 × O2–/F– and 5 × S2– arranged as a monocapped square antiprism), copying the arrangement around the Er3+ cations in PbFCl-type ErFS. The three-dimensional structure of Er3OF3S2 is built up of S2– sheets and {}^2_\infty[OF3Er3]4+ double layers, which are formed by strongly contorted tetrahedral [ZEr4]10.75+ units (Zn– = 25 % O2– + 75 % F–). The crystals of this compound show a prominent superstructure in the tetragonal space group I4/mmm with a = 380.59(3), c = 1892.03(9) pm and Z = 2. In the crystal structures of both title compounds, the light anions O2– and F– occupy one crystallographically unique Wyckoff position in a statistic allocation. Subject to the O/F content in the formulae, the ratio of O2–:F– is 1:1 in Er3OFS3 and 1:3 in Er3OF3S2.

The laccase-catalyzed reaction between catechols and heterocyclic 1,3-dicarbonyls (pyridinones, quinolinones, thiocoumarins) using aerial oxygen as the oxidant delivers benzofuropyridinones, benzofuroquinolinones, and thiocoumestans in a simple fashion, highly regioselectively with yields ranging from 55 to 98%. With barbituric acid derivatives the exclusive formation of dispiropyrimidinone derivatives takes place. The unambiguous and complete structure elucidation of all reaction products has been achieved by means of NMR spectroscopic methods (HSQMBC and band-selective HMBC) as well as by X-ray crystal structure analysis.

Combining the concepts of noninnocent behavior of metal/ligand entities and the coupling of redox-active moieties via an electronically mediating bridge led to the synthesis and the structural, electrochemical, and spectroscopic characterization of [Cl(Q)Ru(mu-tppz)Ru(Q)Cl](n) where Q(o) is 4,6-di-tert-butyl-N-phenyl-o-iminobenzoquinone and tppz(o) is 2,3,5,6-tetrakis(2-pyridyl)pyrazine, the available oxidation states being Ru(II,III,IV), Q(o,*-,2-), and tppz(o,*-,2-). One-electron transfer steps between the n = (2-) and (4+) states were studied by cyclic voltammetry and by EPR, UV-vis-NIR spectroelectrochemistry for the structurally characterized anti isomer of [Cl(Q)Ru(mu-tppz)Ru(Q)Cl](PF(6))(2), 2(PF(6))(2), the only configuration obtained. The combined investigations reveal that 2(2+) is best described as [Cl(Q(*-))Ru(III)(mu-tppz(o))Ru(III)(Q(*-))Cl](2+) with antiferromagnetic coupling between the ruthenium(III) and the iminosemiquinone components at each end. A metal-based spin as evident from large g factor anisotropy (EPR) and an intense intervalence absorption band at 1850 nm in the near-infrared (NIR) suggest that oxidation occurs at both iminosemiquinones to yield two Ru(II,III)-bonded quinones, implying redox-induced electron transfer. Reduction takes place stepwise at the metal centers yielding iminosemiquinone complexes of Ru(III,II) as evident from radical complex EPR spectra with small (99,101)Ru hyperfine contributions. After complete metal reduction to ruthenium(II) the bridging ligand tppz is being reduced stepwise as apparent from typical NIR absorption bands around 1000 nm and from small g anisotropy of the monoanion [Cl(Q(*-))Ru(II)(mu-tppz(*-))Ru(II)(Q(*-))Cl](-). A structure-based DFT calculation confirms the Ru-Cl character of the HOMO and the iminoquinone-dominated LUMO and illustrates the orbital interaction pattern of the five electron transfer active components in this new system.

The lanthanide chloride ortho-oxomolybdates LnCl[MoO4] (Ln = Sm–Yb) crystallize in the monoclinic space group C2/m (a = 1035–1010 pm, b = 736–713 pm, c = 691–678 pm, β = 106.7–107.4°, Z = 4), while LuCl[MoO4] displays a triclinic structure (space group P, a = 591.42(2) pm, b = 716.19(3) pm, c = 681.44(3) pm, α = 93.724(2)°, β = 102.463°, γ = 122.134(2)°, Z = 2). The isotypical monoclinic derivatives exhibit one crystallographically unique site for the lanthanide cations with a coordination number of eight (2 × Cl– and 6 × O2– arranged as trigonal dodecahedra). The Lu3+ cations in LuCl[MoO4] also occupy a single crystallographic position, but with a coordination number of only seven (2 × Cl– and 5 × O2–, arranged as monocapped trigonal prisms). The coordination polyhedra around the lanthanide cations in the LnCl[MoO4] representatives (Ln = Sm–Yb) are connected to each other via three common edges, building up a ∞2{[LnCl2/2eO4/2eO2/1t]6–} layer parallel to the ab plane. These layers are cross-linked along [001] by Mo6+ cations, which on their part form tetrahedral ortho-oxomolybdate units [MoO4]2–. In LuCl[MoO4] only two edges of the [LuCl2O5] polyhedra are interconnected, constituting a ∞1{[LuCl2/2eO2/2eO3/1t]6–} chain along [100]. These chains arrange as a sheered primitive rod-packing with the Mo6+ cations connecting these strands to each other, again by the formation of tetrahedral [MoO4]2– entities. Magnetic measurements were performed for GdCl[MoO4] and DyCl[MoO4], exhibiting Curie-Weiss behaviour for both compounds. Luminescence and excitation spectra of EuCl[MoO4] and TbCl[MoO4] were measured. Under UV excitation both bulk materials show intense red and green luminescence, respectively. This is slightly uncommon, since most bulk compounds do not show intense luminescence due to concentration quenching.

Studies of the reactions between an unsymmetrically substituted 1,1-diaminodiphosphine and electron poor alkenes revealed that, in contrast to the regioselective 1,2-addition of the P−P bond to α,β...

The halide derivatives of yttrium ortho-oxomolybdate YX[MoO 4] (X = F, Cl) both crystallize in the monoclinic system with four formula units per unit cell. YF[MoO 4] exhibits a primitive cell setting (space group P21/ c; a = 519.62(2) pm, b = 1225.14(7) pm, c = 663.30(3) pm, beta = 112.851(4) degrees ), whereas the lattice of YCl[MoO 4] shows face-centering (space group C2/m; a = 1019.02(5) pm, b = 720.67(4) pm, c = 681.50(3) pm, beta = 107.130(4) degrees ). The two compounds each contain crystallographically unique Y (3+) cations, which are found to have a coordination environment of six oxide and two halide anions. In the case of YF[MoO 4], the coordination environment is seen as square antiprisms, and for YCl[MoO 4], trigon-dodecahedra are found. The discrete tetrahedral [MoO 4] (2-) units of the fluoride derivative are exclusively bound by six terminal Y (3+) cations, while those of the chloride compound show a 5-fold coordination around the tetrahedra with one edge-bridging and four terminal Y (3+) cations. The halide anions in each compound exhibit a coordination number of two, building up isolated planar rhombus-shaped units according to [Y 2F 2] (4+) in YF[MoO 4] and [Y 2Cl 2] (4+) in YCl[MoO 4], respectively. Both compounds were synthesized at high temperatures using Y2O3, MoO3, and the corresponding yttrium trihalide in a molar ratio of 1:3:1. Single crystals of both are insensitive to moist air and are found to be coarse shaped and colorless with optical band gaps situated in the near UV around 3.78 eV for the fluoride and 3.82 eV for the chloride derivative. Furthermore, YF[MoO 4] seems to be a suitable material for doping to obtain luminescent materials because the Eu (3+)-doped compound shows an intense red luminescence, which has been spectroscopically investigated.

K 3 Gd 3 [PS 4 ] 4 and K 9 Gd[PS 4 ] 4 form by the reaction of gadolinium, red phosphorus and sulfur with appropriate portions of K 2 S at 950 °C for 14 days in evacuated torch-sealed silica ampoules. Both structures contain isolated [PS 4 ] 3− tetrahedra ( d (P–S) = 201–208 pm) and eightfold coordinated Gd 3+ cations ( d (Gd–S) = 278–307 pm). K 3 Gd 3 [PS 4 ] 4 which is isotypic with K 3 Ho 3 [PS 4 ] 4 crystallizes monoclinically in the space group C 2/ c ( a = 1601.87(9) pm, b = 1162.48(6) pm, c = 1452.39(8) pm, β = 90.773(5)°; Z = 4). The structure is built up of a three-dimensional network of edge-sharing {Gd[PS 4 ] 4 } 9− polyhedra with the K + cations located in channels along [1 1 0]. K 9 Gd[PS 4 ] 4 which is pseudo-isotypic with K 9 Ce[PS 4 ] 4 crystallizes also monoclinically but in the space group C 2 ( a = 2021.93(12) pm, b = 979.35(6) pm, c = 1747.08(11) pm, β = 115.661(5)°; Z = 4) as inversion-twinned crystals. In the crystal structure, one-dimensional chains of edge-sharing [GdS 8 ] 12− polyhedra can be found which are separated by the potassium cations. Thereby three of the four Gd 3+ positions (two times 2 a , two times 2 b ) are partially inhabited by K + cations in amounts of about 87, 79 and 23%, so that statistically even isolated {Gd[PS 4 ] 4 } 9− units must occur.

Two related non-centrosymmetric, cubic, quaternary chalcogenides, containing europium have been synthesized employing the molten flux method and by the reaction of europium halides with the ternary seleno-germanate, Na6Ge2Se6. The reactions of Eu, Ge and Se were accomplished in a molten Na2Se2 flux at 800 °C for 150 h in an evacuated fused silica ampoule and yielded Na2EuGeSe4 (I). Similarly, Na0.75Eu1.625GeSe4 (II), could be synthesized at slightly lower temperature (750 °C) with a different starting ratio of Eu, Ge, Se and Na2Se2. A reaction between EuCl3 and Na6Ge2Se6 in 1:2 ratio at 650 °C for 96 h in an evacuated fused silica ampoule yielded Na2EuGeSe4 (I), while the reaction between EuI2 and Na6Ge2Se6 in 1:1 ratio under similar conditions yielded Na0.75Eu1.625GeSe4 (II). Crystal data for these compounds are as follows: I, cubic, space group I4¯3m (no. 217), a=7.3466(3), Z=2; II, cubic, space group I4¯3d (no. 220), a=14.7065(8), Z=16. The crystal structures of I and II are closely related and can be compared to a CsCl-type and its ordered superstructure, respectively. These compounds are semiconductors with optical band gaps around 2 eV. The temperature dependence of the magnetic susceptibility indicated that both compounds are paramagnetic with μeff.=7.6 and 7.73 μB, for I and II, respectively, close to the theoretical value of 7.94 μB for Eu2+. Raman spectroscopic characterization of the compounds is also reported.

A new family of Ag-substituted pseudoquaternary alkali-seleno-germanates has been synthesized by two solid-state routes: the conventional flux method and metathesis. This family includes a series of semiconductors with varying amounts of Ag+ substituted for Na+ in Na8Ge4Se10 to form AgxNa(8-x)Ge4Se10, [x = 0.31 (I), 0.67 (II), 0.77 (III), 0.87 (IV), 1.05 (V), 1.09 (VI)] and another phase with a different composition AgxNa(6-x)Ge2Se7 (x = 1.76), VII, related to Na6Ge2Se7. In I-VI, Ge4Se10(8-) constitutes a 6-membered chairlike unit with a Ge-Ge bond, while in VII, a corner-shared dimer of GeSe4 tetrahedra (Ge2Se76-) acts as the building unit. The single-crystal structure analysis indicates that there is a phase transition from P to C2/c, in changing from pure Na8Ge4Se10 to AgxNa(8-x)Ge4 Se10 (I-VI), while there is no phase transition between pure Na6Ge2Se7 and AgxNa(6-x)Ge2Se7 (x = 1.76). The structures of I-VI may be described in terms of layers of cubic close-packed Se2- anions. In between the Se layers, octahedral holes fully occupied by Na+ and mixed Ag+/Na+ cations alternate with layers formed of octahedral holes fully occupied by Na+ and Ge26+ cations. Two adjacent Ge26+ cations form a chairlike Ge4Se10(8-) anion in which Ge-Ge bonds are oriented almost parallel to the Se layers. In contrast, VII does not have close-packed anions. Corner-shared GeSe4 tetrahedra (Ge2Se7(6-) dimer) and AgSe4 tetrahedra form layers that are cross-linked by Na/AgSe4 tetrahedra to form a 3-dimensional (3-D) structure. An optical property investigation indicates a red shift in the band gap of AgxNa(8-x)Ge4Se10 (x = 0.67)(II) as compared to that of pure Na8Ge4Se10. Raman data also indicate a red shift of the Ge-Se stretching mode in the Ag+-substituted phase II (x = 0.67) compared to that of Na8Ge4Se10.

Single crystals of the ternary copper(I) lanthanide(III) sulfides with the composition CuMS2 (M = Dy - Lu) are formed within seven days at 750 °C by oxidation of elemental copper and lanthanide metal with sulfur (molar ratio: 1 : 1 : 2, evacuated silica tubes) in equimolar quantities of CsCl, CsBr or CsI as fluxing agents. The CuYS2-type crystal structures (orthorhombic, Pnma, Z = 4; e. g. CuDyS2: a = 1342.51(9), b = 397.96(3), c = 627.43(5) pm and CuLuS2: a = 1315.06(9), b = 391.04(3), c = 624.18(5) pm) exhibit chains of cis edge-linked [CuS4]7− tetrahedra with the composition 1 ∞{[Cu(S1)3/3(S2)1/1]3−} which run parallel to [010] and show hexagonal rod packing. Charge compensation and three-dimensional interconnection of these anionic strands occur via octahedrally coordinated M3+ cations surrounded by six S2− anions. These [MS6]9− octahedra share vertices and edges to form a three-dimensional network 3 ∞{[M(S1)3/3(S2)3/3]−} with the ramsdellite-type topology of γ-MnO2. The metal sulfur distances within the [MS6] polyhedra are very similar (M-S: 263 - 279 pm), whereas those within the [CuS4] units cover the ranges 227 - 230 (Cu-S2) and 231 - 233 (Cu-S1) as well as 250 - 252 pm (Cu-S1′, 2×). The present work is the first comprehensive X-ray single crystal diffraction study of the complete isotypic B-type series CuMS2 (M = Dy - Lu).

Quaternary strontium copper selenides with the trivalent lanthanides exhibit the simple formula SrCuMSe3, but occur in three orthorhombic structures (with Z = 4) depending upon the radius of the M3+ cation. For SrCuLaSe3 (a = 848.82(5) pm, b = 423.04(3) pm, c = 1671.23(9) pm, space group: Pnma) with the largest lanthanide ion (closed-shell 4f0 La3+) coordination numbers of seven are realized for both high-charged cations (Sr2+ and La3+: CN = 7). For SrCuGdSe3 (a = 1068.10(7) pm, b = 410.79(3) pm, c = 1349.21(8) pm, space group: Pnma) with an intermediate lanthanide ion (half-filled shell 4f7 Gd3+) Sr2+ shows the same (CN = 7), whereas Gd3+ reveals a diminished coordination number (CN = 6). For SrCuLuSe3 (a = 404.98(3) pm, b = 1345.67(8) pm, c = 1040.19(7) pm, space group: Cmcm) with the smallest lanthanide ion (closed-shell 4f14 Lu3+) the coordination number of Lu3+ remains unchanged (CN = 6), but Sr2+ gains an extra Se2− ligand to expand its coordination sphere (CN = 8). In all three selenides the Cu+ cations have only four Se2− anions as next neighbours, so the crystal structures can be described as being built up by vertex-sharing [CuSe4]7− tetrahedra (d(Cu+–Se2−) = 245–252 pm), which form infinite chains { ∞ 1 [ CuS e 2 / 1 S e ′ 2 / 2 ] 5 − } running along [0 1 0] in SrCuLaSe3 or SrCuGdSe3 and [1 0 0] in SrCuLuSe3, respectively. SrCuLaSe3 crystallizes with the PbCuLaS3-type structure and an equimolar distribution of the Sr2+ and La3+ cations over both monocapped trigonal prismatically coordinated sites. SrCuGdSe3 prefers the Eu2CuS3- (according to EuIICuEuIIIS3) and SrCuLuSe3 the KCuZrS3-type structure, which both contain layers of edge- and vertex-shared [MSe6]9− octahedra and display a Cmcm–Pmcn group–subgroup relationship.

Single crystals of the ternary copper(I) lanthanide(III) sulfides with the composition CuMS2 (M = La - Nd, Sm, Gd, Tb) form within seven days at 800 °C by oxidation of elemental copper and lanthanide metal with sulfur (molar ratio: 1 : 1 : 2) in evacuated silica tubes when equimolar quantitites of CsCl are present as flux. The crystal structures (monoclinic, P21/c, Z = 4; e. g. CuLaS2: a = 662.04(6), b = 730.89(6), c = 692.73(6) pm, β = 98.741(7)° and CuTbS2: a = 639.13(6), b = 700.02(6), c = 670.46(6) pm, β = 98.214(7)°) exhibit corrugated layers 2 ∞ {[Cu(S1)3/3(S2)1/1]3−} parallel to (100) which consist of vertex-linked pairs of [CuS4]7− tetrahedra sharing a common edge ([Cu2S6]10−). Their three-dimensional cross-linkage is achieved by M3+ cations in monocapped trigonal prismatic coordination of seven S2− anions. The metal sulfur distances in the [CuS4]7− units cover with 230 - 233 (Cu-S2) and 231 - 238 (Cu-S1) as well as 241 - 248 (Cu-S1’) and 245 - 251 pm (Cu-S1”) a rather broad range, whereas those within the [MS7]11− polyhedra lie relatively closer together (M-S: 276 - 307 pm). The present work is the first comprehensive account of the knowledge acquired from X-ray single-crystal diffraction data for the whole isotypic series CuMS2 (M = La - Nd, Sm, Gd, Tb).

Quaternary strontium copper(I) lanthanoid(III) selenides are formed by the oxidation of elemental strontium, copper and the corresponding lanthanoid with selenium. Orange to red needle-shaped single crystals of SrCuPrSe3 and SrCuCeSe3 have been synthesized by heating mixtures of Sr, Cu, Pr / Ce and Se with CsI as a flux in evacuated silica tubes to 800°C for 7 d. Both compounds crystallize orthorhombically in space group Pnma with four formula units per unit cell, but with unlike lattice constants (a = 1097.32(6), b = 416.51(2), c = 1349.64(8) pm for SrCuPrSe3 and a = 846.13(5), b = 421.69(2), c = 1663.42(9) pm for SrCuCeSe3) and therefore different structure types. The Pr3+ cations in SrCuPrSe3 are surrounded octahedrally by six Se2− anions forming chains of edge-sharing [PrSe6]9− octahedra that are joined by common vertices. Together with [CuSe4]7− tetrahedra they form [CuPrSe3]2− layers piled up parallel (001). Between those layers the Sr2+ cations are coordinated by seven Se2− anions in the shape of capped trigonal prisms linking the structure in the third dimension. On the other hand in SrCuCeSe3 the Ce3+ cations as well as the Sr2+ cations adopt a coordination number of seven. Since the bonding distances between cerium and selenium match with those of strontium and selenium the two crystallographically independent sites of these cations are occupied statistically by Ce3+ and Sr2+ with equal ratios. Nevertheless, there is a close structural relationship between SrCuPrSe3 and SrCuCeSe3. Similar to SrCuPrSe3 where Cu+ and Pr3+ cations together with Se2− anions form [CuPrSe3]2− layers parallel (001), the Cu+ cations and [(Ce1/Sr1)Se7]11.5− polyhedra in SrCuCeSe3 build strongly puckered layers which are connected by (Ce2)3+/(Sr2)2+ cations. The copper selenium part in both compounds correlates as well, with [CuSe4] 7− tetrahedra linked by common vertices to form [CuSe3]5− chains running along [010].

Durch Oxidation eines Gemenges aus Kupfer- und Lanthanoid-Metall mit elementarem Selen im molaren Verhaltnis von 1 : 1 : 2 erhalt man in evakuierten Quarzglasampullen durch Zugabe von CsCl innerhalb einer Woche bei 750 °C quaternare Caesium-Kupfer(I)-Lanthanoid(III)-Selenide vom Formeltyp CsCu3M2Se5 (M = Sm, Gd — Lu). Ein Uberschus an CsCl fordert als Flusmittel das Wachstum der goldgelben bzw. roten, nadelformigen, hydrolysebestandigen Einkristalle. Die Kristallstruktur von CsCu3M2Se5 (M = Sm, Gd — Lu) (orthorhombisch, Cmcm, Z = 4; z. B. CsCu3Sm2Se5: a = 417, 84(3), b = 1470, 91(8), c = 1764, 78(9) pm bzw. CsCu3Lu2Se5: a = 407, 63(3), b = 1464, 86(8), c = 1707, 21(9) pm) enthalt Doppelstrange aus kantenverknupften [MSe6]9—-Oktaedern, die entlang [100] verlaufen und uber Eckenverknupfung zweidimensionale Schichten parallel (010) ausbilden. Zwei kristallographisch unterschiedliche Cu+-Kationen, die ihrerseits stark gewellte Schichten aus kanten- bzw. eckenverknupften [CuSe4]7—-Tetraedern bilden, vernetzen die {[M2Se5]4—}-Teilstruktur zu einem dreidimensionalen Gerust der Zusammensetzung {[Cu3M2Se5]—}. Es bleiben Kanale langs [100] frei, in welche die Cs+-Kationen eingelagert werden. Mit acht Cs—Se-Abstanden zwischen 348 und 368 sowie einem neunten, der je nach Lanthanoid zwischen 437 (fur M = Sm) bzw. 440 pm (fur M = Lu) liegt, ergibt sich als Koordinationsfigur ein (2+1)-fach uberkapptes trigonales Prisma fur Cs+. Quaternary Cesium Copper(I) Lanthanoid(III) Selenides of the Type CsCu3M2Se5 (M = Sm, Gd — Lu) By oxidation of mixtures of copper and lanthanoid metal with elemental selenium in molar ratios of 1 : 1 : 2 and in addition of CsCl quaternary cesium copper(I) lanthanoid(III) selenides with the formula CsCu3M2Se5 (M = Sm, Gd — Lu) were obtained at 750 °C within a week from torch-sealed evacuated silica tubes. An excess of CsCl as flux helps to crystallize golden yellow or red, needle-shaped, water-resistant single crystals. The crystal structure of CsCu3M2Se5 (M = Sm, Gd — Lu) (orthorhombic, Cmcm, Z = 4; e. g. CsCu3Sm2Se5: a = 417.84(3), b = 1470.91(8), c = 1764.78(9) pm and CsCu3Lu2Se5: a = 407.63(3), b = 1464.86(8), c = 1707.21(9) pm, respectively) contains [MSe6]9— octahedra which share edges to form double chains running along [100]. Those are further connected by vertices to generate a two-dimensional layer parallel to (010). By edge- and vertex-linking of [CuSe4]7— tetrahedra two crystallographically different Cu+ cations build up two-dimensional puckered layers parallel to (010) as well. These sheet-like structure interconnects the {[M2Se5]4—} layers to create a three-dimensional network according to {[Cu3M2Se5]—}. Thus empty channels along [100] form, apt to take up the Cs+ cations. These are surrounded by eight plus one Se2— anions in the shape of (2+1)-fold capped trigonal prisms with Cs—Se distances between 348 and 368 pm (8×) and 437 (for M = Sm) or 440 pm (for M = Lu), respectively, for the ninth ligand.

Single crystals of CuSm 3 Se 6 develop by reaction of the elements (Cu, Sm and Se; molar ratio: 1:3:6) after 7 days at 973 K. As the formula indicates, the crystal structure of CuSm 3 Se 4 [Se 2 ] (orthorhombic, Pbcm ; a =709.53(6), b =783.91(7), c =1689.98(9) pm, Z =4) contains both mono- (Se 2− ) and diselenide anions ([Se 2 ] 2− ). The latter are surrounded by six Sm 3+ cations. If the diselenide units serve as one fragment, they form irregular {[Se 2 ]Sm 6 } 16+ octahedra, which produce chains running along [010]. Together with [SeSm 4 ] 10+ tetrahedra they build up a two-dimensional layer parallel to (001) according to ∞ 2 {(Sm 3 Se[Se 2 ]) 5+ }. Vertex-, edge- and face-shared [CuSe 4 ] 7− tetrahedra compose chains running along [010] as well. Since the distance between the two central cations of a face-shared bitetrahedron ( d (Cu–Cu)=115 pm) is much too short, the copper position is only half occupied. A three-dimensional network is created by stacking ∞ 2 {(Sm 3 Se[Se 2 ]) 5+ } layers and ∞ 1 {(CuSe 3 ) 5− } chains parallel to (001).

Derbe, gelblichgrune Einkristalle des ternaren Kupfer(I)-Praseodym(III)-Sulfids CuPrS2 entstehen bei der Umsetzung der Elemente (Kupfer, Praseodym und Schwefel) im molaren Verhaltnis von 1:1:2 innerhalb von sieben Tagen bei 800°C in evakuierten Quarzglasampullen, wenn aquimolare Mengen an CsCl als Flusmittel zugegen sind. Versuche zur Darstellung von CuPr3S5 oder CuPr5S8 liefern unter analogen Reaktionsbedingungen statt der erhofften Zielverbindungen stets zweiphasige Gemenge aus CuPrS2 und Pr2S3 (C—Typ). Die Kristallstruktur von CuPrS2 (monoklin, P21/c; a = 655, 72(6); b = 722, 49(6); c = 686, 81(6)pm, β = 98, 686(7)°; Z = 4) weist parallel (100) angeordnete gewellte Schichten {[Cu(S1)3/3(S2)1/1]3—} aus eckenverknupften Doppeln ([Cu2S6]10—) zweier [CuS4]7—-Tetraeder mit gemeinsamer Kante auf, die durch Pr3+-Kationen in uberkappt-trigonal-prismatischer Siebenerkoordination von S2—-Anionen dreidimensional vernetzt werden. Die Metall-Schwefel-Abstande in den [CuS4]-Einheiten uberstreichen mit 233 (Cu—S2) und 236 (Cu—S1) sowie 247 (Cu—S1′) und 248pm (Cu—S1″) ein recht weites Intervall, wahrend jene (Pr—S: 284—304pm) in den [PrS7]-Polyedern vergleichsweise eng beieinanderliegen. C—Pr2S3 kristallisiert gemas Pr2, 677□0, 333S4 mit Z = 4 in einer kationendefekten Th3P4-Struktur (kubisch, I4¯3d; a = 857, 68(7) pm; Z = 5, 333 fur Pr2S3). Entsprechend der Niggli-Formel {PrS8/5, 333} ist Pr3+ von acht S2— in Abstanden von 287 (4×) und 307pm (4×) trigondodekaedrisch koordiniert. Weder die Einkristallrontgenstrukturanalyse noch Elektronenstrahl-Mikrosondenuntersuchungen zeigen eine Evidenz fur den Einbau von Cu+-Kationen in diese Kristallstruktur. Single Crystals of A—type CuPrS2 and C—type Pr2S3 from Attempts to Synthesize Ternary Copper(I) Praseodymium(III) Sulfides Coarse, yellowish-green single crystals of the ternary copper(I) praseodymium(III) sulfide CuPrS2 form within seven days at 800°C by oxidation of elemental copper and praseodymium with sulfur (molar ratio: 1:1:2) in evacuated silica tubes when equimolar quantitites of CsCl are present as flux. Attempts to synthesize CuPr3S5 or CuPr5S8 under analogous conditions always yield two-component mixtures of CuPrS2 and Pr2S3 (C type) instead of the desired target compounds. The crystal structure of CuPrS2 (monoclinic, P21/c; a = 655.72(6), b = 722.49(6), c = 686.81(6)pm, β = 98.686(7)°; Z = 4) exhibits undulated layers {[Cu(S1)3/3(S2)1/1]3—} parallel (100) which consist of vertex-linked pairs of two [CuS4]7— tetrahedra ([Cu2S6]10—) sharing a common edge. Their three-dimensional cross-linkage is achieved by Pr3+ cations in monocapped trigonal prismatic coordination of seven S2— anions each. The metal sulfur distances in the [CuS4] units cover with 233 (Cu—S2) and 236 (Cu—S1) as well as 247 (Cu—S1′) and 248pm (Cu—S1″) a rather broad interval, whereas those (Pr—S: 284—304 pm) within the [PrS7] polyhedra lie relatively closer together. According to Pr2.677□0.333S4 (with Z = 4), C—Pr2S3 crystallizes in a cation-deficient Th3P4-type structure (cubic, I4¯3d; a = 857.68(7) pm; Z = 5.333 for Pr2S3). In conformity with the Niggli formula {PrS8/5.333} Pr3+ is surrounded trigon-dodecahedrally by eight S2— at distances of 287 (4×) and 307pm (4×). Neither the X-ray single-crystal structure refinement nor electron-beam microprobe analyses leave any evidence for the incorporation of Cu+ cations into this crystal structure.

Tb4N2Te3 (I) and Dy4N2Te3 (II) are prepared by reacting Tb or Dy with NaN3, Te, I2, and NaI as flux (evacuated silica tubes, 950 °C, 7 d).

Solid-state reactions of La2O3, LaBr3, and MoO3 in molar ratios of 1:1:3 lead to single crystals of LaBrMoO4 among a few by-products, which emerge from redox reactions of Br– with hexavalent molybdenum. To obtain the analogous cerium compound, Ce2O3 was synthesized in situ by using CeO2 and Ce in a 3:1 molar ratio. The two rare-earth metal bromide ortho-oxidomolybdates(VI) REBrMoO4 (RE = La and Ce) crystallize isotypically in the monoclinic space group Pc (a = 982 – 977 pm, b ≈ 581 pm, c = 810 – 803 pm, β ≈ 90°, Z = 4). In the crystal structure, two crystallographically unique RE3+ cations are present, both with similar coordination environments of three plus one Br– and six O2– anions in the shape of distorted tetracapped trigonal prisms. The two distinguishable Br– anions both display coordination spheres of three plus one RE3+ cations each, building up distorted tetrahedra. These are fused together via four common edges to form anti-PbO-type 2∞{[BrRE]2+} layers (e = edge-connecting) parallel to the (100) plane. Two crystallographically different oxidomolybdate(VI) units are also found in the structure, which can be best described as strands of apically vertex-shared [MoO5]4– trigonal bipyramids along [001] represented by the formula 1∞{[MoOO]2–} (v = vertex-connecting, t = terminal). The aforementioned 2∞{[BrRE]2+} layers and the 1∞ {[MoOO]2–} chains are alternately stacked along the a axis. The peculiarity of this structure is expressed by the position of the Mo6+ cations, which are not situated in the center of the bipyramids, but reside offset in a trigonal pyramid. Since both the (Mo1)6+ and the (Mo2)6+ cations are located in the same partial tetrahedron, relative to the triangular plane of the trigonal bipyramid, a structure description in a non-centrosymmetric space group is immanent. Both title compounds display a twinned crystal structure with strong similarities to those of the chloride homologues REClMoO4 (RE = La – Pr) and LaClWO4.

The Cu(I)-catalyzed reaction of 1-bromo-2-iodobenzenes and other 1,2-dihalobenzenes with 1,3-cyclohexanediones in DMF at 130 °C using Cs2CO3 as a base and pivalic acid as an additive selectively delivers 3,4-dihydrodibenzo[b,d]furan-1(2H)-ones with yields ranging from 47 to 83%. The highly regioselective domino process is based on an intermolecular Ullmann-type C-arylation followed by an intramolecular Ullmann-type O-arylation. Substituted products are accessible by employing substituted 1-bromo-2-iodobenzenes and substituted 1,3-cyclohexanediones as substrates. Reaction with an acyclic 1,3-diketone yields the corresponding benzo[b]furan.

The treatment of excess zinc in the presence of ammonium chloride under ammonothermal conditions of 873 K and 97 MPa leads to diamminetriamidodizinc chloride [Zn2(NH3)2(NH2)3]Cl with a two-dimensionally μ-amido-interconnected substructure. Similar reaction conditions using ammonium bromide instead of the chloride (773 K, 230 MPa) result in diamminemonoamidozinc bromide [Zn(NH3)2(NH2)]Br with one-dimensional infinite μ-amido-bridged chains. Both compounds were obtained as colorless, very moisture sensitive crystals. Crystal structures and hydrogen bond schemes are analyzed. Raman spectroscopic data of the chloride are reported.

Single crystals of the new title compound in the form of black, hexagonal plates are grown in a BaCl2 flux.

La3FMo4O16 crystallizes in the triclinic crystal system with space group P1 ¯ [a = 724.86(2) pm, b = 742.26(2) pm, c = 1469.59(3) pm, α = 101.683(2)°, β = 102.118(2)°, γ = 100.279(2)°] with two formula units per unit cell. The three crystallographically independent La 3+ cations show a coordination number of nine each, with one F – and eight O 2– anions forming distorted monocapped square antiprisms. The fluoride anion is coordinated by all three lanthanum cations to form a nearly planar triangle. Besides three crystallographically independent tetrahedral [MoO4] 2– units, a fourth one with a higher coordination number (CN = 4 +1) can be found in the crystal structure, forming a dimeric entity with a for