Potassium oxoantimonate(V), K3[SbO4]

The oxoantimonate K₃[SbO₄] crystallizes in the monoclinic space group P2/c with the Na₃[BiO₄] structure type. The structure contains chains of [SbO₆] octahedra connected via common edges. All K and Sb atoms lie on twofold axes, i.e. 0,y, or ,y,.     

Potassium oxoaluminate ­antimonate(III), K2[Al2Sb2O7]

Dipotassium dialuminium diantimonate, K₂[Al₂Sb₂O₇], crystallizes in the trigonal space group . The structure is isotypic with K₂Pb₂Ge₂O₇ and consists of [Al₂Sb₂O₇]^2? layers containing Al³⁺ in a nearly regular tetrahedral and Sb³⁺ in a Ψ‐tetrahedral environment of O ligands.     

Tetraphenylphosphonium-Heptathiacyclo-thioarsenat(III), PPh4[SAsS7]

Tetraphenylphosphonium Heptathiacyclo Thioarsenate(III), PPh₄[SAsS₇] From PPh₄[As₂SCl₅] und K₂S₅ the title compound was obtained in acetonitrile among other products. According to an X-ray crystal structure analysis, it crystallizes in the orthorhombic space group Pna2₁ with a = 1 826.1(3), b = 1 312.0(2), c = 1 215.9(2) pm, Z = 4. The structure consists of PPh₄⁺ and [SAsS₇]^? ions, AsS₇ rings in the crown conformation as in S₈ being present.     

Potassium thiocyanate argentates: K3[Ag(SCN)4], K4[Ag2(SCN)6] and K[Ag(SCN)2]

The anions of the title compounds contain [Ag(SCN)₄] units, with the S atoms coordinating to Ag⁺ in a tetrahedral arrangement. Whereas in the isolated anions of tripotassium tetra­thio­cyanatoargentate(I), K₃[Ag(SCN)₄], (I), all SCN^? groups are bonded as terminal ligands, in tetrapotassium di‐μ‐thio­cyanato‐S:S‐bis­[dithio­cyanato­argentate(I)], K₄[Ag₂(SCN)₆], (II), two AgS₄ tetrahedra share one common edge. In poly[potassium [argentate(I)‐di‐μ‐thio­cyanato‐S:S]], K[Ag(SCN)₂], (III), edge‐ and vertex‐sharing of AgS₄ tetrahedra results in infinite [Ag(SCN)₂]^? layers.     

Neue Oxoferrate(III). Na2Li3[FeO4] und K2Li3[FeO4]

New Oxoferrates (III). Na₂Li₃[FeO₄] and K₂Li₃[FeO₄] . Na₂Li₃[FeO₄] and K₂Li₃[FeO₄] (transparent, pink or light yellow single crystals) have been prepared by heating mixtures of the oxides (Na:Li:Fe = 2.2:3.3:1; Ag-tube, 720°C, 27 d or K:Li:Fe = 2.2:3.3:1; analogous, 700°C, 40 d). Na₂Li₃[FeO₄] is isotypic with Na₂Li₃[GaO₄] (a = 832.2(1), b = 796.0(1), c = 656.3(1)pm, Pnnm) and K₂Li₃[FeO₄] with K₂Li₃[GaO₄] (a = 557.7(1), b = 880.6(1), c = 1101.8(2)pm, β = 111.51(2)°, P2₁/c). Four cycle diffractometer data: MoK_α, 525 out of 686 I₀(hkl), R = 9.36%, R_w = 5.97% or 1424 out of 1424 I₀(hkl), R = 8.45%, R_w = 5.66%. Parameters see text. The structures are characterized by calculations of the Madelung Part of Lattice Energy, MAPLE. The Effective Coordination Numbers, ECoN, which are calculated by means of Mean Fictive Ionic Radii, MEFIR, are compared with the analogous gallates.     

Potassium selective calix[4]semitubes

A new class of ionophore consisting of two calix[4]arene units linked through the lower rim by two ethylene chains, in combination with propyl ether and phenolic functional groups, has been developed. These calix[4]semitube molecules exhibit remarkable selectivity and fast complexation kinetics for potassium over all Group 1 metal cations. Molecular modelling studies, using structural models derived from crystallographic data, suggest the potassium cation is complexed by a horizontal, side-on route and not through the calix[4]arene annulus. The length of the bridging alkylene chain between the respective calix[4]arenes of the semitube structure dictates the strength and selectivity of alkali metal cation binding.     

Alkaline metal oxoantimonates(III), A3[SbO3] (A = K or Cs)

The two title trialkaline trioxoantimonates(III), tripotassium trioxoantimonate(III), K₃[SbO₃], (I), and tricaesium trioxo­antimonate(III), Cs₃[SbO₃], (II), crystallize in the cubic Na₃[AsS₃] structure type in space group P2₁3. The structures show discrete Ψ-tetrahedral [SbO₃]³⁻ anions with C_3v point-group symmetry. The Sb—O distances are 1.923 (4) Å in (I) and 1.928 (2) Å in (II), and the O—Sb—O bond angles are 99.5 (2)° in (I) and 100.4 (1)° in (II).     

Das erste oligomere Oxoferrat(III): K14[Fe4O13]

The First Tetraferrate(III): K₁₄[Fe₄O₁₃] For the first time K₁₄[Fe₄O₁₃] was obtained by annealing intimate mixtures of K₂O and LiFeO₂ (molar ratio 2.2:1) in closed Ni-cylinders (6 months, 610°C) in the form of yellow-brown single crystals. The structure determination (four circle diffractometer, MoKα, 3377 of 3377 I_o(hkl); R = 4,52%, R_w = 2,53%) confirms the space group P2₁/c; a = 677.9, b = 2956.2, c = 672,1 pm, β = 120.31°, Z = 2. Essential part of the structure are tetranuclear [Fe₄O₁₃]^14?-groups, oligomers consisting of four corner-sharing FeO₄-tetrahedra. Within the structure these groups are connected by two crystallographically distinct K-particles thus forming bands which are arranged according to a ?closest packing of bands”? interconnected by the rest of the K-particles. The structure is described via Schlegel-diagrams. It is isotypic with Na₁₄[Al₄O₁₃].     

Das erste oligomere Oxoindat(III): K14[In4O13]

The First Oligooxoindate(III): K₁₄[In₄O₁₃] For the first time K₁₄[In₄O₁₃] was obtained by heating intimate mixtures of K₂O, CdO and elementar In (molar ratio 3.1:1.0:1.0) in closed Ag-cylinders (30 days, 450°C) in form of yellow-brown single crystals. The structure determination by four circle diffractometer data MoKα, 3 689 out of 3 689 I_o(hkl), R = 4.22, R_w = 2.45) confirms the space group P2₁/c with lattice constants a = 687.7 pm; b = 3 118.5 pm; c = 686.4 pm; β = 119.3°; Z = 2. The characteristic feature of the structure is [In₄O₁₃]^14? groups, oligomers consisting of four corner-sharing InO₄ tetrahedra. These groups are connected by crystallographically distinct potassium atoms. The structure is isotypic with Na₁₄[Al₄O₁₃] [2] and K₁₄[Fe₃O₁₃] [3]. ECoN and MAPLE calculationes are discussed.     

Potassium gallium hydrogenphosphate fluoride,K2Ga[H(HPO4)2]F2

Hydrothermally synthesized dipotassium gallium {hydrogen bis[hydrogenphosphate(V)]} difluoride, K₂Ga[H(HPO₄)₂]F₂, is isotypic with K₂Fe[H(HPO₄)₂]F₂. The main features of the structure are ([Ga{H(HPO₄)₂}F₂]²⁻)_n columns consisting of centrosymmetric Ga(F₂O₄) octahedra [average Ga—O = 1.966 (3) Å and Ga—F = 1.9076 (6) Å] stacked above two HPO₄ tetrahedra [average P—O = 1.54 (2) Å] sharing two O‐atom vertices. The charge‐balancing seven‐coordinate K⁺ cations [average K—O,F = 2.76 (2) Å] lie in the intercolumn space, stabilizing a three‐dimensional structure. Strong [O...O = 2.4184 (11) Å] and medium [O...F = 2.6151 (10) Å] hydrogen bonds further reinforce the connections between adjacent columns.     

Darstellung und Kristallstruktur von Tetraphenylphosphonium-Hexathiocyanatorhodat(III), [P(C6H5)4]3[Rh(SCN)6]

Preparation and Crystal Structure of Tetraphenylphosphonium Hexathiocyanatorhodate(III), [P(C₆H₅)₄]₃[Rh(SCN)₆] By treatment of RhCl₃ · n H₂O with KSCN in water a mixture of the linkage isomers [Rh(NCS)_n(SCN)_6–n]^3?, n = 0–2 is formed which is separated by ion exchange chromatography on diethylaminoethyl cellulose. The X-ray structure determination on a single crystal of [P(C₆H₅)₄]₃[Rh(SCN)₆] (monoclinic, space group C1c1, a = 13.620(5), b = 22.929(13), c = 22.899(9) Å, β = 98.55(3)°, Z = 4) confirms the coordination of all ligands via S with the middle Rh? S distance of 2.372 Å and Rh? S? C angles of 109°. The SCN groups are nearly linear with 175° and averaged bondlengths S? C 1.63 and C? N 1.14 Å. The crystal lattice is build up by layers of complex anions and voluminous cations with no specific interactions but which are closely connected by thiocyanate ligands and phenyl rings.     

Visible and near-infrared intense luminescence from water-soluble lanthanide [Tb(III), Eu(III), Sm(III), Dy(III), Pr(III), Ho(III), Yb(III), Nd(III), Er(III)] complexes

The synthesis of a new ligand (1) containing a single phenanthroline (phen) chromophore and a flexibly connected diethylenetriamine tetracarboxylic acid unit (DTTA) as a lanthanide (Ln) coordination site is reported [1 is 4-[(9-methyl-1,10-phenantrol-2-yl)methyl]-1,4,7-triazaheptane-1,1,7,7-tetraacetic acid]. From 1, an extended series of water-soluble Ln.1 complexes was obtained, where Ln is Eu(III), Tb(III), Gd(III), Sm(III), Dy(III), Pr(III), Ho(III), Yb(III), Nd(III), and Er(III). The stoichiometry for the association was found 1:1, with an association constant K(A) > or = 10(7) s(-1) as determined by employing luminescence spectroscopy. The luminescence and photophysical properties of the series of lanthanide complexes were investigated in both H2O and D2O solutions. High efficiencies for the sensitized emission, phi(se), in air-equilibrated water were observed for the Ln.1 complexes of Eu(III) and Tb(III) in the visible region (phi(se) = 0.24 and 0.15, respectively) and of Sm(III), Dy(III), Pr(III), Ho(III), Yb(III), Nd(III), and Er(III) in the vis and/or near-infrared region [phi(se) = 2.5 x 10(-3), 5 x 10(-4), 3 x 10(-5), 2 x 10(-5), 2 x 10(-4), 4 x 10(-5), and (in D2O) 4 x 10(-5), respectively]. For Eu.1 and Tb.1, luminescence data for water and deuterated water allowed us to estimate that no solvent molecules (q) are bound to the ion centers (q = 0). Luminescence quenching by oxygen was investigated in selected cases.     

Das erste Oxid vom Formeltyp K5[MO4]: K5[TIO4] [1]

The First Oxide with the Formula Type K₅[MO₄]: K₅[TlO₄] Light yellow powder and pale yellow transparent single crystals of K₅[TlO₄] were newly prepared from mixtures of binary oxides (K₂O/Tl₂O₃) preheated and levigated several times [closed Ag-cylinder, 580°C, 24 h and 600°C, 20 d]. Space group Pbca with a = 1170.4(3), b = 686.1(1), c = 2079.2(5) pm, Z = 8 [four-circle-diffraktometer data, 997 I₀(hkl), R = 7.87%, R_w = 5.63%, MoKα] (parameter s. text). The crystal structure belongs to the Na₅[GaO₄] type. Structural aspects, ECoN and MAPLE are discussed.