Shi-Xiong Liu

Crystal structure of a cyanide-bridged heptanuclear manganese(III)–chromium(III) complex with a ground state S = 21/2

K3[Cr(CN)6] reacts with the mononuclear MnIII complex Mn(salen)ClO4 · 2H2O [salen: N,N′-ethylenebis(salicylideneiminato)dianion] to give a bimetallic heptanuclear complex cation salt [Cr{(CN)Mn(salen · H2O)}6][Cr(CN)6]6H2O. In the complex anion, [Cr{(CN)Mn(salen · H2O)}6]3+, six MnIII ions coordinate to a CrIII center via cyano bridges, forming a spherical species with 3 symmetry. A study of magnetic properties shows the presence of antiferromagnetic interaction through the cyanide bridge between CrIII (S = 3/2) and MnIII (S = 4/2) and results in a ground state S = 21/2.

Syntheses and structures of chalcogen–molybdenum clusters; [Mo3XSe6{S2P(OEt)2}3]Cl, [Mo3X(SeS)3{S2P(OEt)2}3]I and [Mo3 XSe3{S2P(OEt)2}4(py)] (X=0.65S+0.35Se, py= C5H5N)

The trinuclear Mo cluster [Mo3(μ3–X)(μ2–Se2)3{S2P-(OEt)2}3]Cl (X=0.65S+0.35Se) (1) has been synthesised by reacting MoCl3·3H2O with ZnSe and [Me4N][S2P(OEt)2] in an EtOH/HCl medium. Reduction of (1) by Ph3P in the presence of [Me4N]-[S2P(OEt)2] and pyridine gave [Mo3(μ3–X)(μ2–Se)3 {S2P(OEt)2}4(py)] (X=0.65S+0.35Se, py=C5H5N) (2). Complex (2) was, in turn, converted into [Mo3(μ3–X)(μ2–SeS)3{S2P(OEt)2}3]I (X=0.65S+0.35Se) (3) by treatment with H2S and I2. The structures of complexes (1), (2) and (3) were established by X-ray crystallography.

An oxygen-centred tetranuclear tantalum cluster : Ta4O(Te2)4TeI4

Tetratantalum nonatellurium tetraiodide oxide exhibits a one-dimensional structure containing distorted tetrahedral oxygen-centred tetranuclear clusters of Ta atoms. Each of the four shorter Ta-Ta bonds is bridged by a Te 2 group, and each Ta atom is also bonded to a terminal I atom and a μ4 0 atom. A μ4 Te atom connects two neighbouring clusters to form a one-dimensional chain along the b axis. The chains are held together by van der Waals interactions.

A dimeric copper(II) complex of an α-hydroxylated acid : [Cu(C14H8O3)(C9H7N)(H2O)]2.2C3H7NO.2H2O

The structure of bis[μ-(9-hydroxy-1:2κ 2 O)-9-fluorene-carboxylato(2-)]-1κO;2κO-bis[aqua(quinoline-κN)-copper(II)] bis(dimethylformamide) dihydrate has been determined by single-crystal X-ray diffraction. The binuclear Cu II unit comprises a pair of Cu atoms linked by two hydroxy O-atom bridges. The coordination polyhedron around each Cu atom is a distorted square pyramid, the basal plane consisting of one N atom from the quinoline ligand, one carboxy O atom and two bridging O atoms from two α-hydroxylated acid ligands, while the axial coordination site is occupied by an O atom of the coordinated water molecule with a Cu-O bond length of 2.424 (4) A.

A New One-Dimensional Compound: (TaTe4)6I4(TaI6)

The title compound, hexakis(tetratelluriotantalum) tetraiodide hexaiodotantalate, has a [TaTe 4 ] n chain structure with TaI 6 - complex anions and I anions between the chains. The [TaTe 4 ] n chain contains rectangular antiprismatic TaTe 8 polyhedra, each Ta atom being coordinated by four Te 2 groups. The Ta atom in the TaI 6 - complex anion is octahedrally coordinated by I-anions.