Composition and crystal structure of SmSb2O4Cl revisited : and the analogy of Sm1.5Sb1.5O4Br

The quaternary halide‐containing samarium(III) oxidoantimonates(III) Sm1.3Sb1.7O4Cl and Sm1.5Sb1.5O4Br were synthesized through solid‐state reactions from the binary components (Sm2O3, Sb2O3 and SmX3, X = Cl and Br) at 750 °C in evacuated fused silica ampoules. They crystallize tetragonally in the space group P4/mmm, like the basically isotypic bismuthate(III) compounds SmBi2O4Cl and SmBi2O4Br, but show larger molar volumes and therefore contradict an ideal composition of “SmSb2O4X” (X = Cl and Br). Both single‐crystal X‐ray diffraction and quantitative electron‐beam microprobe analysis revealed the actual compositions of the investigated antimony(III) compounds, which can be understood as heavily Sm3+‐doped derivatives of “SmSb2O4X” hosts at the Sb3+ site. (Sm1)3+ is coordinated eightfold by oxygen atoms in the shape of a cube. The mixed‐occupied (Sb/Sm2)3+ cation has four oxygen atoms and four halide anions as neighbors forming a square antiprism. The oxygen atoms and anions establish alternating layers parallel to the ab‐plane, which alternate when stacked along [001].Projekt DEA

Synthesis, crystal structures and spectroscopic properties of pure YSb2O4Br and YSb2O4Cl as well as Eu3+- and Tb3+-doped samples

The quaternary halide-containing yttrium(iii) oxidoantimonates(iii) YSb(2)O(4)Cl and YSb(2)O(4)Br were synthesised through solid-state reactions from the binary components (Y(2)O(3), Sb(2)O(3) and YX(3), X = Cl and Br) at 750 °C in evacuated fused silica ampoules with eutectic mixtures of NaX and CsX (X = Cl and Br) as fluxing agents. YSb(2)O(4)Cl crystallizes tetragonally in the non-centrosymmetric space group P42(1)2 with unit-cell parameters of a = 773.56(4) pm and c = 878.91(6) pm, whereas YSb(2)O(4)Br is monoclinic (space group: P2(1)/c) with a = 896.54(6) pm, b = 780.23(5) pm, c = 779.61(5) pm and β = 91.398(3)°, both for Z = 4. The two new YSb(2)O(4)X compounds contain [YO(8)](13−) polyhedra, which are connected via four common edges to form [Image: see text] layers (d(Y(3+)–O(2−)) = 225–254 pm) without any Y(3+)⋯X(−) bonds (d(Y(3+)⋯X(−)) > 400 pm). Moreover, all oxygen atoms belong to ψ(1)-tetrahedral [SbO(3)](3−) units, which are either connected to four-membered rings [Sb(4)O(8)](4−) in the chloride (Y(2)[Sb(4)O(8)]Cl(2) for Z = 2) or endless chains in the bromide (Y(1/2)(SbO(2))Br(1/2) for Z = 8) by common vertices. With distances of 307 pm in YSb(2)O(4)Cl and 326 pm in YSb(2)O(4)Br there are not even substantial bonding Sb(3+)⋯X(−) (X = Cl and Br) interactions at work. Luminescence spectroscopy on samples doped with trivalent europium and terbium showed an energy transfer from the oxidoantimonate(iii) moieties as the sensitizer in the host structure onto the lanthanoid activators

The triclinic lanthanoid(III) halide oxidoarsenates(III) Sm3Cl2[As2O5][AsO3] and Tm3Br2[As2O5][AsO3]

Pale yellow single crystals of the composition Ln3X2[As2O5][AsO3] (Ln = Tm for X = Br and Ln = Sm for X = Cl) were obtained via solid‐state reactions in the systems Ln2O3/As2O3 from sealed silica ampoules using different halides as fluxing agents. Sm3Cl2[As2O5][AsO3] and Tm3Br2[As2O5][AsO3] crystallize isotypically in the triclinic space group P1 with Z = 2 and cell parameters of a = 543.51(4) pm, b = 837.24(6) pm, c = 1113.45(8) pm, α = 90.084(2)°, β = 94.532(2)°, γ = 90.487(2)° for the samarium and a = 534.96(4) pm, b = 869.26(6) pm, c = 1081.84(8) pm, α = 90.723(2)°, β = 94.792(2)° γ = 90.119(2)° for the thulium compound. The isotypic crystal structure of both representatives exhibits three crystallographically different Ln3+ cations, each with a coordination number of eight. (Ln1)3+ and (Ln2)3+ are only coordinated by three oxygen atoms, whereas (Ln3)3+ shows additional contacts to halide anions in forming square [LnO4X4]9- antiprisms. All As3+ cations are surrounded by three oxygen atoms in the shape of isolated [AsO3]3- ψ1‐tetrahedra. They occur either isolated or condensed as pyroanionic [As2O5]4- units with a bridging oxygen atom. In both anions, non‐binding lone‐pair electrons are present at the As3+ cations with a pronounced stereochemically active function

Three new lanthanum oxoantimonate(III) halides : synthesis and crystal structure of La5Cl3[SbO3]4, La2Sb12O19Br4 and La2Sb12O19I4

It was possible to synthesize colorless single crystals of La5Cl3[SbO3]4 (block-shaped) as well as La2Sb12O19Br4 and LaSb12O19I4 (both needle-shaped), representing three new compounds from the system of lanthanum oxoantimonate(III) halides, which have not been described in the literature before. La5Cl3[SbO3]4 crystallizes in the monoclinic space group P2/c with the lattice parameters a = 895.82(5) pm, b = 564.28(3) pm, c = 1728.19(9) pm, and β = 90.007(2)° for Z = 2. This layered compound contains isolated ψ1-tetrahedral [SbO3]3- units, square hemiprisms [LaO8]13-, and antiprisms [LaO4Cl4]9-, La2Sb12O19Br4 and LaSb12O19I4 crystallize isotypically in the orthorhombic space group Pnma with a = 3184.69(19) pm, b = 417.78(3) pm, c = 1019.85(6) pm for the bromide and a = 3215.08(19) pm, b = 419.94(3) pm, c = 1062.89(6) pm for the iodide. Instead of isolated [SbO3]3- anions, semi-tubular features 1∞{[Sb12O19]2-} are present, which consist mainly of [SbO4]5- and few [SbO3]3- units with stereochemically active electronic lone pairs at their Sb3+ centers. Within these so-called “double-halfpipes”, La3+ is surrounded by nine oxygen atoms as [LaO9]15- polyhedron without any contact with X- anions. Single-crystal Raman measurements were performed for La5Cl3[SbO3]4 and LaSb12O19I4, and La5Cl3[SbO3]4 was structurally compared with the isostoichiometric, but not isotypic La5F3[SbO3]4.State of Baden-Württember

Synthesis and crystal structure of the short LnSb2O4Br series (Ln = Eu-Tb) and luminescence properties of Eu3+-doped samples

Pale yellow crystals of LnSb2O4Br (Ln = Eu-Tb) were synthesized via high temperature solid-state reactions from antimony sesquioxide, the respective lanthanoid sesquioxides and tribromides. Single-crystal X-ray diffraction studies revealed a layered structure in the monoclinic space group P21/c. In contrast to hitherto reported quaternary lanthanoid(III) halide oxoantimonates(III), in LnSb2O4Br the lanthanoid(III) cations are exclusively coordinated by oxygen atoms in the form of square hemiprisms. These [LnO8]13- polyhedra form layers parallel to (100) by sharing common edges. All antimony(III) cations are coordinated by three oxygen atoms forming ψ1-tetrahedral [SbO3]3- units, which have oxygen atoms in common building up meandering strands along [001] according to {[SbO2/2O1/1]-}-1 (v = vertex-sharing, t = terminal). The bromide anions are located between two layers of these parallel running oxoantimonate(III) strands and have no bonding contacts with the Ln3+ cations. Since Sb3+ is known to be an efficient sensitizer for Ln3+ emission, photoluminescence studies were carried out to characterize the optical properties and assess their suitability as light phosphors. Indeed, for both, GdSb2O4Br and TbSb2O4Br doped with about 1.0-1.5 at-% Eu3+ efficient sensitization of the Eu3+ emission could be detected. For TbSb2O4Br, in addition, a remarkably high energy transfer from Tb3+ to Eu3+ could be detected that leads to a substantially increased Eu3+ emission intensity, rendering it an efficient red light emitting material

The Triclinic Lanthanoid(III) Halide Oxidoarsenates(III) Sm3Cl2[As2O5][AsO3] and Tm3Br2[As2O5][AsO3]

Pale yellow single crystals of the composition Ln(3)X(2)[As2O5][AsO3] (Ln = Tm for X = Br and Ln = Sm for X = Cl) were obtained via solid-state reactions in the systems Ln(2)O(3)/As2O3 from sealed silica ampoules using different halides as fluxing agents. Sm3Cl2[As2O5][AsO3] and Tm3Br2[As2O5][AsO3] crystallize isotypically in the triclinic space group P (1) over bar with Z = 2 and cell parameters of a = 543.51(4) pm, b = 837.24(6) pm, c = 1113.45(8) pm, a = 90.084(2)degrees, beta = 94.532(2)degrees, gamma = 90.487(2)degrees for the samarium and a = 534.96(4) pm, b = 869.26(6) pm, c = 1081.84(8) pm, a = 90.723(2)degrees, beta = 94.792(2)degrees gamma = 90.119(2)degrees for the thulium compound. The isotypic crystal structure of both representatives exhibits three crystallographically different Ln(3+) cations, each with a coordination number of eight. (Ln1)(3+) and (Ln2)(3+) are only coordinated by three oxygen atoms, whereas (Ln3)(3+) shows additional contacts to halide anions in forming square [LnO(4)X(4)](9-) antiprisms. All As3+ cations are surrounded by three oxygen atoms in the shape of isolated [AsO3](3-) psi(1)-tetrahedra. They occur either isolated or condensed as pyroanionic [As2O5](4-) units with a bridging oxygen atom. In both anions, non-binding lone-pair electrons are present at the As3+ cations with a pronounced stereochemically active function

The monoclinic rare earth metal(III) chloride oxidoarsenates(III) with the composition RE5Cl3 [AsO3](4) (RE = La-Nd, Sm)

The rare earth metal(III) chloride oxidoarsenates(III) with the composition RE5Cl3[AsO3](4) (RE= La-Nd, Sm) could be synthesized via solid-state methods through the reaction of arsenic sesquioxide (As2O3) with the corresponding rare earth metal compounds (La2O3, CeO2 + metallic Ce, Pr6O11, Nd2O3 or metallic Sm) using several chloride-containing fluxing agents in evacuated silica glass ampoules. The compounds build up non-isotypic crystal structures in the monoclinic space groups C2/c for RE= La-Pr, and P2/c for RE= Nd and Sm. All rare earth metal(III) cations exhibit coordination numbers of eight. While (RE1)(3+) and (RE2)(3+) are only surrounded by oxygen atoms in the form of distorted square antiprisms or prisms, (RE3)(3+) is coordinated square antiprismatically by four oxygen atoms and four chloride anions. Although the coordination polyhedra in both structures differ only marginally, their connection patterns show more pronounced differences. This regards especially the (RE)(3+) cations and results from different site symmetries of the (Cl1)(-) anions. All As3+ lone-pair cations are coordinated by three oxygen atoms to form psi(1)-tetrahedral [AsO3](3-) complex anions with their non-binding (lone) electron pairs pointing into empty channels along [010]

Functionalized branched EDOT-terthiophene copolymer films by electropolymerization and post-polymerization “click”-reactions

The electrocopolymerization of 3,4-ethylenedioxythiophene (EDOT) with the branched thiophene building block 2,2′:3′,2″-terthiophene (3T) is presented as a versatile route to functional polymer films. Comparisons to blend systems of the respective homopolymers PEDOT and P3T by in situ spectroelectrochemistry and Raman spectroscopy prove the successful copolymer formation and the access to tailored redox properties and energy levels. The use of EDOT-N3 as co-monomer furthermore allows modifications of the films by polymer analogous reactions. Here, we exemplarily describe the post-functionalization with ionic moieties by 1,3-dipolar cycloaddition (“click”-chemistry) which allows to tune the surface polarity of the copolymer films from water contact angles of 140° down to 40°