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The reaction of ZrCl4 with oleum (65 % SO3) in the presence of Ag2SO4 at 250 °C yielded colorless single crystals of Zr(S2O7)2 [orthorhombic, Pccn, Z = 4, a = 709.08(6) pm, b = 1442.2(2) pm, c = 942.23(9) pm, V = 963.5(2) × 106 pm3]. Zr(S2O7)2 shows Zr4+ ions in an eightfold distorted square antiprismatic coordination of oxygen atoms belonging to four chelating disulfate units. Each S2O72– ion is connected to a further Zr4+ ion leading to chains according to 1∞[Zr(S2O7)4/2]. The same reaction at a temperature of 150 °C resulted in the formation of Ag4[Zr(S2O7)4] [monoclinic, C2/c, Z = 4, a = 1829.35(9) pm, b = 704.37(3) pm, c = 1999.1(1) pm, β = 117.844(2)°, V = 2277.6(2) × 106 pm3]. Ag4[Zr(S2O7)4] exhibits the unprecedented [Zr(S2O7)4]4– anion, in which the central Zr4+ cation is coordinated by four chelating disulfate units. Thus, in Ag4[Zr(S2O7)4] the 1∞[[Zr(S2O7)4/2] chains observed in Zr(S2O7)2 are formally cut into pieces by the implementation of Ag+ ions.

Two hexagonal series of lanthanoid(III) oxide fluoride selenides with similar structure types can be obtained by the reaction of the components MF3, M2O3, M, and Se in sealed niobium tubes at 850 °C using CsI as fluxing agent. The compounds with the lighter and larger representatives (M = La – Nd) occur with the formula M6O2F8Se3, whereas with the heavier and smaller ones (M = Nd, Sm, Gd – Ho) their composition is M2OF2Se. For both systems single-crystal determinations were used in all cases. The compounds crystallize in the hexagonal crystal system (space group: P63/m) with lattice parameters of a = 1394–1331 pm and c = 403–372 pm (Z = 2 for M6O2F8Se3 and Z = 6 for M2OF2Se). The (M1)3+ cations show different square antiprismatic coordination spheres with or without an extra capping fluoride anion. All (M2)3+ cations exhibit a ninefold coordination environment shaped as tricapped trigonal prism. In both structure types the Se2– anions are sixfold coordinated as trigonal prisms of M3+ cations, being first condensed by edges to generate trimeric units and then via faces to form strands running along [001]. The light anions reside either in threefold triangular or in fourfold tetrahedral cationic coordination. For charge compensation, both structures have to contain a certain amount of oxide besides fluoride anions. Since F– and O2– can not be distinguished by X-ray diffraction, bond-valence calculations were used to address the problem of their adjunction to the available crystallographic sites.

The quaternary thioaluminogermanates Na(AlS2)(GeS2) (1) and K(AlS2)(GeS2) (2) crystallize in the tetragonal space group I4/mcm (no. 140) with unit cell parameters a = 7.4274(11) A, c = 5.8560(12) A for Na(AlS2)(GeS2) and a = 7.8826(2) A, c = 5.8642(4) A for K(AlS2)(GeS2). The crystal structure comprises of one-dimensional [(AlS2)(GeS2)]– anionic chains with Al and Ge sharing the tetrahedral site. The alkali metal cations fill the square antiprismatic voids between chains. Both 1 and 2 are semiconductors with bandgap of around 3.6 eV and 3.5 eV, respectively.

A new type of ionic ferroelectric based on a chiral salen-type Schiff base erbium(III) complex (ErL) was synthesized by the reaction of erbium nitrate with the ligand N,N′-bis(3,5-dichlorosalicylidene)-(1S,2S)-1,2-cyclohexylenediamine (L). The structures of the ligand L and the complex ErL were determined by single-crystal X-ray diffraction. The results indicated that ErIII not only acts as central metal atom to coordinate with two Schiff base ligands, but also as Lewis acid catalyst to promote the partial decomposition of another salen-type Schiff base ligand. The central ErIII atom adopts an octacoordinate square antiprismatic arrangement with Λ absolute configuration, coordinating with all nitrogen and oxygen atoms of two ligands due to the influence of the strong electron-withdrawing group on the Schiff base ligand. The complex ErL exhibits good SHG and ferroelectric properties. The results provide a simple and effective approach to construct rare earth complexes coordinated with nitrogen and oxygen atoms of salen-type Schiff base ligands with technologically important properties such as SHG activity and ferroelectricity.

Three ternary rare earth [NdIII (1), SmIII (2) and YIII (3)] complexes based on 3-[(4,6-dimethyl-2-pyrimidinyl)thio]-propanoic acid (HL) and 1,10-phenanthroline (Phen) were synthesized and characterized by IR and UV/Vis spectroscopy, TGA, and single-crystal X-ray diffraction. The crystal structures showed that complexes 1–3 contain dinuclear rare earth units bridged by four propionate groups and are of general formula [REL3(Phen)]2·nH2O (for 1 and 2: n = 2; for 3: n = 0). All rare earth ions are nine-coordinate with distorted mono-capped square antiprismatic coordination polyhedra. Complex 1 crystallizes in the monoclinic system, space group P21/c with a = 16.241(7) A, b = 16.095(7) A, c = 19.169(6) A, β = 121.48(2)°. Complex 2 crystallizes in the monoclinic system, space group P21/c with a = 16.187(5) A, b = 16.045(4) A, c = 19.001(4) A, β = 120.956(18)°. Complex 3 crystallizes in the triclinic system, space group P1 with a = 11.390(6) A, b = 13.636(6) A, c = 15.958(7) A, α = 72.310(17)°, β = 77.548(15)°, γ = 78.288(16)°. The antioxidant activity test shows that all complexes own higher antioxidant activity than free ligands.

The Schiff base N,N′-bis(salicylidene)-1,5-diamino-3-oxapentane (H2L) and its lanthanide(III) complexes, PrL(NO3)(DMF)(H2O) (1) and Ho2L2(NO3)2·2H2O (2), were synthesized and characterized by physicochemical and spectroscopic methods. Single crystal X-ray structure analysis revealed that complex 1 is a discrete mononuclear species. The PrIII ion is nine-coordinate, forming a distorted capped square antiprismatic arrangement. Complex 2 is a centrosymmetric dinuclear neutral entity in which the HoIII ion is eight-coordinate with distorted square antiprismatic arrangement. The DNA-binding properties of H2L and its LnIII complexes were investigated by spectrophotometric methods and viscosity measurements. The results suggest that the ligand H2L and its LnIII complexes both connect to DNA in a groove binding mode; the complexes bind more strongly to DNA than the ligand. Moreover, the antioxidant activities of the LnIII complexes were in vitro determined by superoxide and hydroxyl radical scavenging methods, which indicate that complexes 1 and 2 have OH· and O2–· radical scavenging activity.

The neutral thorium complex Th(NCSe)4(OP(NMe2)3)4 and homoleptic octa(isoselenocyanato)uranate anion U(NCSe)84– in (Pr4N)4U(NCSe)8·2CFCl3 (1) were synthesised and structurally characterised. (Pr4N)4U(NCSe)8·2CFCl3 contains the UIV anion U(NCSe)84– and was characterised using IR spectroscopy and single-crystal X-ray diffraction. Th(NCSe)4(OP(N(CH3)2)3)4·0.5CH3CN·0.5H2O (2) was characterised using IR and Raman spectroscopy, as well as 31P{1H}, 15N{1H}, 14N{1H}, 13C{1H}, 1H and 77Se NMR spectroscopy and structurally characterised using single-crystal X-ray diffraction. The U(NCSe)84– anion and Th(NCSe)4(OP(N(CH3)2)3)4·0.5CH3CN·0.5H2O complex are the first structurally characterised actinide-isoselenocyanates. The crystal structures shows an approximate square antiprismatic arrangement of the ligands around the actinide(IV) atoms.

Pale violet, needle-shaped single crystals of the new neodymium(III) oxide chloride oxoselenate(IV) Nd7O5Cl3[SeO3]4 were obtained by the reaction of Nd2O3 and NdCl3 with SeO2 (molar ratio: 3:1:4) in evacuated silica ampoules within seven days at 775 °C, if an excess of CsCl worked as fluxing agent. Nd7O5Cl3[SeO3]4 crystallizes in the triclinic space group P with the lattice parameters a = 694.46(4), b = 944.53(5), c = 1567.92(9) pm, α = 87.821(3), β = 81.849(3), γ = 84.852(3)° and Z = 2. Its structure exhibits seven crystallographically different Nd3+ cations, of which (Nd1)3+ – (Nd4)3+ are coordinated by O2– anions forming distorted square prisms. The polyhedra of (Nd1)3+ and (Nd2)3+ receive additional caps by one Cl– anion each, and (Nd5)3+ – (Nd7)3+ show mixed square antiprismatic environments of O2– and Cl– anions too. However, the polyhedra of (Nd5)3+ and (Nd6)3+ include two, the polyhedron about (Nd7)3+ even three Cl– anions. Two-dimensional layers of edge- and vertex-linked [ONd4]10+ tetrahedra are built up by (O1)2– – (O5)2– together with all Nd3+ cations. All the other oxygen atoms belong to four crystallographically different Se4+ cations erecting ψ1-tetrahedral oxoselenate(IV) units [SeO3]2– with stereochemically active non-bonding electron pairs (“lone pairs”) pointing into the free space between the layers. Three independent Cl– anions in threefold coordination of Nd3+ cations interconnect the layers to form a three-dimensional network, thereby achieving the charge balance.

Two isostructural complexes [Ca(hssal)(H2O)2]n (1) and [Sr(hssal)(H2O)2]n (2) (hssal2– = 5-sulfosalicylate anion) are obtained byusing the ligand 5-sulfosalicylic acid and alkaline earth metal salts under hydrothermal conditions. Their structures were determined by single-crystal X-ray diffraction analysis and further characterized by elemental analyses and IR spectroscopy. Complexes 1 and 2 have a two-dimensional network structure, in which the CaII and SrII ions have an octacoordinate distorted square antiprismatic arrangement. Each sulfosalicylate anion acts as a μ4-bridging ligand, whereas the carboxylate group adopts a chelating coordination. Luminescence properties and thermal stabilities of complexes 1 and 2 were investigated.

Ho11ClTe16O48: An Extremly Chlorine-Poor Chloride Oxotellurate(IV) of Trivalent Holmium While attempting to synthesize Ho2Te3O9 by reacting Ho2O3 with TeO2 (800 °C, 12 d) chloride from the CsCl flux was incidently mobilized and as by-product, Ho11ClTe16O48 (triclinic, ; a = 551.52(3), b = 1193.54(6), c = 1834.63(9) pm, α = 100.814(3), β = 95.443(3), γ = 100.175(3)°; Z = 1), the first example of this new composition in the field of lanthanoid(III) chloride oxotellurates(IV) has been obtained. The six crystallographically different Ho3+ cations experience a six-, seven- and eightfold coordination through oxygen atoms (d(Ho3+−O2−) = 221 – 280 pm), leading to octahedral, triangle-square polyhedral, capped trigonal prismatic and square antiprismatic coordination figures. Initially, the corresponding [HoOn] polyhedra convene to layers parallel to the (001) plane via edge and corner sharing which again combine to a [Ho11O48]63− network via other individual [(Ho6)O6] octahedra and [(Ho2)2O4/2O4/1] chains along [100], whose three-dimensional characteristic is unique among the lanthanoid(III) oxotellurates(IV) known to date. The eight crystallographically independent Te4+ cations exhibit coordination numbers of 3 and 3+1 in relation to oxygen, except Te1 with 3+1 O2−plus 1 Cl− as anionic neighbours. Apart from isolated [TeO3]2− polyhedra (Ψ1 tetrahedra: d(Te4+−O2−) = 184 – 196 pm) only double and triple groupings occur even in considering secondary Te4+···O2− contacts (d′(Te4+···O2−) = 218 – 264 pm). As with HoCl[TeO3], the tellurium-oxygen partial structure does not get beyond a “zero-dimensional” expression. The Te4+ cations adjust so well while lining the empty cavities within the network, that still only two Te4+-decorated channel types (oval and round) remain unoccupied, offering space for the non-bonding electron pairs (“lone pairs”). The Cl− anions reside in the bigger oval channels (d(Cl−−Te4+) = 286, 352 and 358 pm, 2 × each). In the default of binding Ho3+−Cl− contacts, the correct description of this new compound would thus be holmium(III) oxochlorotellurate(IV) Ho11[Te16O48Cl] according to Ho11[TeO3]2[Te2O6]2[Te3O9]2{Cl[Te2O6]2}. The presence of chloride was not only detected by the structure refinement on the basis of X-ray diffraction data, but also even in such small quantities by elementary analysis with the electron-beam microprobe.

LiRuSn4, LiRhSn4, and LiIrSn4 were prepared by reaction of the elements in sealed tantalum ampoules at 1220 K. The tubes were subsequently annealed at 870 K for one week. The three stannides were investigated by X-ray diffraction on powders and single crystals and the structures were refined from single crystal data: I4/mcm, a = 662.61(3), c = 1116.98(7) pm, wR2 = 0.0730, 283 F2 values for LiRuSn4, a = 658.73(5), c = 1136.4(1) pm, wR2 = 0.0532, 313 F2 values for LiRhSn4 and a = 657.34(5), c = 1130.4(1) pm, wR2 = 0.0343, 176 F2 values for LiIrSn4 with 11 variables for each refinement. LiRuSn4, LiRhSn4, and LiIrSn4 crystallize with a ternary ordered variant of the PdGa5 structure. The transition metal (T) atoms have a square antiprismatic tin environment and they form two-dimensional [TSn4] polyanions with relatively short Ru—Sn (279 pm), Rh—Sn (280 pm), and Ir—Sn (280 pm) distances. The lithium atoms connect the polyanionic [TSn4] layers. They are located in square prismatic voids formed by tin atoms. The crystal chemistry and chemical bonding of these stannides is briefly discussed. Synthese und Struktur der intermetallischen Lithiumstannide LiTSn4 (T = Ru, Rh, Ir) mit geordneter PdGa5-Struktur LiRuSn4, LiRhSn4 und LiIrSn4 wurden aus den Elementen in verschweisten Tantalampullen bei 1220 K hergestellt und anschliesend bei 870 K fur eine Woche getempert. Die drei Stannide wurden uber rontgenographische Pulver- und Einkristallmethoden charakterisiert und die Strukturen wurden anhand von Einkristall-Diffraktometerdaten verfeinert: I4/mcm, a = 662, 61(3); c = 1116, 98(7) pm; wR2 = 0, 0730; 283 F2-Werte fur LiRuSn4, a = 658, 73(5); c = 1136, 4(1) pm; wR2 = 0, 0532; 313 F2-Werte fur LiRhSn4 und a = 657, 34(5); c = 1130, 4(1) pm; wR2 = 0, 0343; 176 F2-Werte fur LiIrSn4 mit 11 variablen Parametern pro Verfeinerung. LiRuSn4, LiRhSn4 und LiIrSn4 kristallisieren in einer ternaren Ordnungsvariante der PdGa5-Struktur. Die Ubergangsmetallatome (T) haben eine quadratisch-antiprismatische Zinnkoordination und sie bilden zweidimensionale [TSn4]-Polyanionen mit relativ kurzen Ru—Sn (279 pm), Rh—Sn (280 pm) und Ir—Sn (280 pm) Abstanden. Die Lithiumatome verbinden die [TSn4]-Polyanionenschichten. Sie sind quadratisch-prismatisch von Zinnatomen koordiniert. Die Kristallchemie und die chemische Bindung dieser Stannide wird kurz diskutiert.

Ga8(C13H9)82– lasst sich durch Umsetzung von Fluorenyllithium mit einer GaIBr-Losung als Lithiumsalz synthetisieren. Die Charakterisierung erfolgte uber eine Einkristallstrukturanalyse, sowie durch DFT-Rechnungen. Die acht Ga-Atome sind quadratisch antiprismarisch angeordnet, wobei jedes Ga-Atom σ-artig an einen Fluorenylliganden gebunden ist. Im Gegensatz zu dem vor kurzem vorgestellten Cluster Ga12(C13H9)102– sollte die Ga8R82–Einheit nach DFT-Rechnungen an den Ga8H82–- und B8H82–-Spezies als closo-Struktur beschrieben werden. The First Molecular Square Antiprismatic Ga8 Cluster exhibiting a closoStructure Ga8(C13H9)82– has been synthesized as a lithium salt from a reaction of fluorenyllithium with a metastable GaIBr solution. It is characterized by X-ray structure analysis and DFT calculations. The eight Ga atoms form a square antiprismatic core and each Ga atom is σ-bonded to a fluorenyl ligand. The Ga8 entity of the cluster is described as a closo compound in contrast to the earlier presented species Ga12(C13H9)102–. This interpretation is based on DFT calculations for Ga8H82– and B8H82–.

An Einkristallen der hydratisierten tetragonalen Cyanokomplexe (NMe4)3Li[Mo(CN)8] · 3,5 H2O (a = 1707,5(3), c = 1054,9(2) pm, Raumgruppe P421m, Z = 4) und Cs7Na[Mo(CN)8]2 · 4,17 H2O (a = 1547,9(1), c = 3254,6(6) pm, I41/a, Z = 8) wurden Rontgenstrukturbestimmungen durchgefuhrt. Die [Mo(CN)8]4–-Polyeder stimmen hinsichtlich ihrer mittleren Abstande Mo–C und C–N (216,7/114,3 pm bzw. 216,1/114,7 pm) im Rahmen der Standardabweichungen uberein, bilden aber im einen Falle ein verzerrtes Dodekaeder ((NMe4)3Li-Komplex), im anderen ein verzerrtes quadratisches Antiprisma (Cs7Na-Komplex). Die Koordination der z. T. hydratisierten Gegenionen, die Ausbildung von Wasserstoffbrucken und die Packung der komplexen Anionen werden diskutiert. Crystal Structures of Octacyanomolybdates(IV). III (NMe4)3Li[Mo(CN)8] · 3.5 H2O and Cs7Na[Mo(CN)8]2 · 4.17 H2O: Examples of Dodecahedral and Square Antiprismatic Eight-Coordination At single crystals of the hydrated tetragonal cyano complexes (NMe4)3Li[Mo(CN)8] · 3.5 H2O (a = 1707.5(3), c = 1054.9(2) pm, space group P421m, Z = 4) and Cs7Na[Mo(CN)8]2 · 4.17 H2O (a = 1547.9(1), c = 3254.6(6) pm, I41/a, Z = 8) X-ray structure determinations were performed. The [Mo(CN)8]4– polyhedra agree with respect to their mean distances Mo–C and C–N (216,7/114,3 pm resp. 216,1/114,7 pm) within their standard deviations, however, there is a distorted dodecahedron in the first case ((NMe4)3Li-complex), and a distorted square antiprism in the second (Cs7Na-complex). The coordination of the counter cations, partly hydrated, the formation of hydrogen bridges and the packing of the complex anions is discussed.