Alexandra Yu. Ledneva

Ionic coordination complexes based on [Re6S8(CN)4L2]n– (L = OH–, NH3; n = 2, 3) cluster anions, and Ni(II) and Cd(II) ammine cations

Two new complexes containing M(II) ammine cations (M = Ni, Cd) and octahedral rhenium(III) thiocyanoammine and thiocyanohydroxoammine cluster anions, [Ni(NH3)6][Re6S8(CN)4(NH3)2]∙2H2O (1) and [Cd(NH3)6][{Cd(NH3)5}{Re6S8(CN)4(OH)(NH3)}]2∙5H2O (2), have been synthesized by hydrothermal reactions starting from Cs1.83K2.17[Re6S8(CN)4(OH)2]∙2H2O. The compounds were structurally characterized by single-crystal X-ray diffraction analysis, elemental analysis, energy dispersive spectroscopy, and IR spectroscopy. Both compounds adopt monoclinic crystal structures composed from discrete ionic species which are held together by multiple hydrogen bonds between CN–, OH–, and NH3 ligands and lattice water. 2 consists of {Cd(NH3)5}2+ attached to the OH group of the [Re6S8(CN)4(OH)(NH3)]3– cluster anion via the Re–OH–Cd linkage.

Hydrogen bonded networks based on hexarhenium(III) chalcocyanide cluster complexes: structural and photophysical characterization

Two series of isostructural compounds resulting from the combination of the four-fold hydrogen bond donors bisamidinium cations, namely 1-2H+ and 2-2H+, and the anionic chalcocyanide clusters of general formula [Re6Qi8(CN)a6]4− are presented (Q = S or Se; where i and a denote inner and apical position, respectively). 1-2H+ is built upon two imidazolium groups linked together by a –(CH2)2– alkyl chain. 2-2H+ is built upon two hydroxyamidinium groups linked together via a phenyl group and, in consequence, it exhibits a planar geometry. This ionic association leads to either two or three-dimensional hydrogen-bonded networks in the solid state, as confirmed by X-ray crystallographic analysis. The solid-state structures arise from the recognition between the pendant –CN ligands of the cluster cores and the amidinium H-bond donors. The luminescence properties of the compounds are investigated in the solid state by means of steady-state and time-resolved techniques. Results are discussed and compared with those measured for the parent Cs4[Re6Si8(CN)a6] and Cs4[Re6Sei8(CN)a6] species. The H-bonded networks display featureless deep-red emission bands centered at λem = 722 and 737 nm and average excited-state lifetimes ranging between 11.5 and 14.8 μs, in accordance with the triplet nature of the radiative process. These photoluminescence properties are similar to the Cs+ homologues and are attributed to the [Re6Qi8]2+ emitting core.

The Research of Temperature Dependences of Electrical Conductivity and Thermopower of WS2 and WSe2 with Partial Replacement of W on Nb

The Research of Temperature Dependences of Electrical Conductivity and Thermopower of WS2 and WSe2 with Partial Replacement of W on Nb Galina E. Yakovleva∗ Nikolaev Institute of Inorganic Chemistry Lavrentiev, 3, Novosibirsk 630090, Russia Anatoly I. Romanenko† Nikolaev Institute of Inorganic Chemistry Lavrentiev, 3, Novosibirsk, 630090 National Research Tomsk State University Lenina, 36, Tomsk, 634050, Russia Alexander S. Berdinsky‡ Novosibirsk State Technical University Marksa, 20, Novosibirsk, 630073, Russia Vitalii A.Kuznetsov§ Nikolaev Institute of Inorganic Chemistry Lavrentiev, 3, Novosibirsk, 630090 Novosibirsk State Technical University Marksa, 20, Novosibirsk, 630073, Russia Alexandra Yu. Ledneva¶ Vladimir E. Fedorov∥ Nikolaev Institute of Inorganic Chemistry Lavrentiev, 3, Novosibirsk, 630090, Russia

Low dimensional solids based on Mo6 cluster cyanides and Mn2+, Mn3+ or Cd2+ metal ions: crystal chemistry, magnetic and optical properties

Five new cluster compounds based on [Mo6Bri8(CN)a6]2− and [Mo6Bri6Qi2(CN)a6]n− (Q = S, Se, n = 3, 4) cluster units have been synthesized and characterized. Structures were determined by X-ray single crystal diffraction techniques and measurements of relevant magnetic susceptibility and optical properties were carried out. [trans-Mn(H2O)2][Mo6Br8(CN)6] (1) crystallizes in the orthorhombic system (Imma space group) and contains 2D square-net-layers built-up from [Mo6Bri8(CN)a6]2− and [trans-M(H2O)2]2+ moieties. Csx[trans-(MnIIxMnIII1−x)(H2O)2][Mo6Br6Q2(CN)6] (Q = S (2) and Se (3)) crystallize in the Imma space group as well; their structures are strongly related to that of 1 with a 2D square net of cluster units and transition metals. They are based on [Mo6Bri6Qi2(CN)a6]3− (Q = S, Se) cluster units whose charge is counter balanced by Cs+ as well as Mn2+ and Mn3+ in high spin states. It is evidenced that the x content of the Cs+ counter-cation is equal to that of Mn2+ in order to maintain – along with (1 − x) Mn3+ – 23 valence electrons per cluster and a 3− charge for the cluster unit. The two oxidation states Mn2+ and Mn3+ were confirmed by electron energy loss spectroscopy (EELS) measurements. (H3O)H[cis-Cd(H2O)2][Mo6Br6Q2(CN)6]–H2O (Q = S (4) and Se (5)) crystallize in the trigonal system (P3121 space group) and are based on [Mo6Bri6Qi2(CN)a6]4− (Q = S, Se) cluster units. In contrast to compounds 1–3, owing to the cis-position of the two water molecules around the transition metal, 4 and 5 exhibit a close-packed 3D structure based on an interpenetrated framework of cluster-based chains. In particular, it contains infinite chains alternating [Mo6Bri6Qi2(CN)a6]4− and H+ protons as linkers. Magnetic and optical properties are also reported as well as theoretical calculations to support the structural analysis and physical properties. Structural analogies with [Re6Qi8(CN)a6]4− based compounds are discussed.