S. B. Artemkina

Inorganic Coordination Polymers Based on Chalcocyanide Cluster Complexes

The paper reports results of experiments involving design of inorganic coordination polymers based on tetrahedral and octahedral chalcocyanide cluster complexes as building blocks. Various approaches to designing three‐dimensional, layered, and chain‐like structures are discussed. Structures of various types are described, and prospects of further studies in this field are outlined.

Adjustment of dimensionality in covalent frameworks formed by Co2+ and rhenium cluster chalcocyanide [Re6S8(CN)6]4-

Abstract The synthesis and X-ray structure of a new cluster compound (Pr4N)2Co[Re6S8(CN)6] · 6H2O is reported. It crystallizes in orthorhombic symmetry, P212121 space group with four formula units per unit cell. The following parameters were found: a = 17.942(9) A, b = 17.979(4) A, c = 16.344(8) A, V=5272 0rA3, ρcalc=2.607 g cm−1; final R=0.0331. The compound was prepared by interaction of layered Cs2Co[Re6S8(CN)6] · 2H2O with aqueous solution of Pr4NBr. This interaction results in cleavage of covalently linked {Co(H2O)2Re6S8(CN)6}2α2− sheets and in formation of isolated fragments {Co(H2O)5Re6S8(CN)6}u2−. Heating of (Pr4N)2Co[Re6S8(CN)6] · 6H2O results in elimination of two water molecules and in formation of (Pr4N)2Co[Re6S8(CN)6] · 4H2O containing infinite -Co(H2O)4-NC-Re6S8(CN) 4-CN-Co(H2O)4-chains.

Colloidal solutions of niobium trisulfide and niobium triselenide

Exfoliated nanomaterials, such as graphene and related few-layered materials, are now widely studied for electronic devices, electrodes and composites, so it is desirable to demonstrate exfoliation of a wider number of layered materials. We have shown that bulk niobium trichalcogenides NbS3 and NbSe3 may be stably dispersed in a number of common organic solvents by ultrasonic treatment. The most concentrated dispersions are obtained in alcoholic media (up to ∼0.443 g L−1). The colloids contain thin well-crystallized nanoribbons of NbS3 and NbSe3. Filtration or spraying of the colloids produces strongly textured thin films with good conducting properties.

New Layered Polymer [{Mn(H2O)3}2{Re6Se8(CN)6}] · 3.3H2O: Synthesis and Properties

The [{Mn(H2O)3}2{Re6Se8(CN)6}] · 3.3H2O complex was produced on slow evaporation of an aqueous solution containing the salt of a cluster complex K4Re6Se8(CN)6 · 3.5H2O and a 23-fold excess of Mn2+. The cluster complexes [Re6Se8(CN)6]4– are linked in a crystal into the charged coordination layers [{Mn(H2O)3}4{Re6Se8(CN)6}3]4–2∞ through the Mn2+ cations. The Mn2+ cations are coordinated in a layer by three cyano nitrogen atoms of the cluster complexes; the Mn–N bond lengths are 2.13(4) and 2.21(2) Å. Each [Re6Se8(CN)6]4– anion is bonded to three manganese cations Mn(1). The anions are bonded additionally to the Mn(2) cations disordered over two close positions.

Structure and thermal properties of the molybdenum complex Mo(acac)3

A method for the synthesis of the Mo(acac)3 complex is proposed and its crystal structure is determined by single crystal X-ray diffraction. Space group P21/c, a = 19.7538(5) Å, b = 7.4821(2) Å, c = 34.6190(8) Å, β = 96.8055(12)°, V = 5080.6(2) Å3, Z = 12. The compound is studied by the thermogravimetric analysis, and MoO3 is shown to be the result of its decomposition.

Crystal structure and magnetic properties of a Cs3Nb2I9 bioctahedral complex

A cluster complex Cs3Nb2I9 is obtained by a high-temperature reaction of niobium, iodine, and cesium iodide. Its crystal structure is determined: trigonal space group P63/mmc, a = 8.2463(3) Å, c = 19.5419(14) Å, V = 1150.84(10) Å3, R(F) = 0.0614. The compound obtained is characterized by temperature independent paramagnetism in the temperature range 70–290 K.

Electroneutral coordination frameworks based on octahedral [Re6(μ3-Q)8(CN)6]4− complexes (Q = S, Se, Te) and the Mn2+ cations

The novel coordination polymers, [{Mn(DMF)3}2{Re6S8(CN)6}] (I), [{Mn(DMF)2(H2O)}2{Re6S8(CN)6}] · 2DMF (II), [{Mn(DMF)3}2{Re6Se8(CN)6}] (III), [{Mn(DMF)2(H2O)}2{Re6Se8(CN)6}] · 2DMF (IV), and [{Mn(DMF)2(H2O)}2{Re6Te8(CN)6}] · 2DMF (V), were synthesized by interaction of the octahedral cluster complexes [Re6(μ3-Q)8(CN)6]4− (Q = S, Se, Te) with the Mn2+ cations in the H2O-DMF mixture. The crystal structures of compounds I, II, IV, and V were determined by X-ray diffraction analysis. The structural analogies between mononuclear cyanometallates and the obtained cluster coordination polymers were discussed.

Heterometallic clusters with the {MoNbI8} core: The synthesis and crystal structures of (Ph4P)2[Mo5NbI8Cl6] and (4-MePyH)5[Mo5NbI8Cl6]Cl2

Heterometallic chloride complexes [Mo5NbI8Cl6]n− (n = 2, 3) are synthesized. The crystal structures of their salts are determined: for (Ph4P)2[Mo5NbI8Cl6] (I), triclinic crystal system, spacegroup P

Effect of anion and cation substitution in tungsten disulfide and tungsten diselenide on conductivity and thermoelectric power

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