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Novel tetranuclear zinc compounds, [Zn4(μ-SeO3)2(μ4-SeO3)2(bipy)4]·11H2O (1) and [Zn4(μ-SeO3)2(μ4-SeO3)2(phen)4]·9H2O (2), which are the first examples of organically templated zinc selenite compounds containing closed-frameworks, have been synthesized via solvothermal processes. The compounds were characterized by spectroscopy, crystallographic methods and DFT calculations.

Phenyltelluroxane clusters of the composition [{(PhTe)19O24}2I18(solv)] (1) are formed during the hydrolysis of [PhTeI3]2 or the oxidation of various phenyltellurium(II) compounds with iodine under hydrolytic conditions. The compounds consist of two half‐spheres with a {(PhTe)19O24}9+ network, which are connected by 18 iodine atoms. The spherical clusters can accommodate solvent molecules such as pyridine or methanol in the center of two rings formed by iodine atoms. The presence of other metal ions during the cluster formation results in a selective replacement of the central {PhTe}3+ units of each half‐sphere as has been demonstrated with the isolation of [{(PhTe)18({Ca(H2O)2}O24}2I16] (2) and [{(PhTe)18({Y(NO3)(H2O)}O24}2I16] (3). A crownether‐like coordination by six oxygen atoms of the telluroxane network is found for the {Ca(H2O}2}2+ and {Y(NO3)(H2O)}2+ building blocks. Mass spectrometric studies show that considerable amounts of the intact clusters are transferred to the gas phase without dissociation., Large telluroxane clusters are formed during the hydrolysis of [PhTeI3]2 or the oxidation of [PhTe]2 with iodine under hydrolytic conditions. They consist of two half‐spheres with {(PhTe)19O24}9+ networks, which are connected by 18 iodine atoms. The central {PhTe}3+ units of each half‐sphere can be replaced by other metal ions. Mass spectrometry shows that the intact clusters are transferred to the gas phase without dissociation.

A ternary silver-mercury-pyridyltellurolate – [Ag4Hg(μ-TeoPy-κTe)3(μ3-TeoPy-κTe)2(μ-TeoPy-κN,Te)(PPh3)2] (1) – was obtained by the reaction of Ag(PPh3)NO3 and Hg(OAc)2 with a solution of LiTeoPy (oPy = 2-pyridyl, Ph = phenyl). In a similar fashion, the cluster [Cu4(μ3-TePh)3Cl(phen)3]⋅0.5C2H6O (2) was obtained when CuCl and 1,10-phenanthroline (phen) reacted with a solution of NaTePh. The alkali-metal aryltellurolate solutions were generated in situ from the reduction of the appropriate diarylditellane with LiBH4 (for 1) or NaBH4 (for 2). Single crystal X-ray diffraction studies were performed, and molecular structures were discussed in detail. Density Functional Theory (DFT) calculations were carried out to better understand the nature of the central moiety connectivity among the metals and the tellurium atoms.

The topological properties of the electron density, ρ(r), and the electron localization function (ELF) are used to study the ground state properties of [M4(µ-EO3)2(µ4-EO3)2(bipy)4] (M = Mn, Fe, Co, Ni, Cu, Zn (d5–10) and E = Se,Te) compounds. The Quantum Theory of Atoms in Molecules was employed, through the use of the Density Functional Theory, to analyze the topological parameters of the M - O and M – N interactions. The results indicate that these interactions are in the transition region (II) between shared to closed-shell (Espinosa et al., 2002). The interactions E–O are in the border region between shared-shell (III) and the intermediate region (II) with dative covalent character. The ELF was used to complete the understanding of the electronic distribution. The topological parameters of the electronic density are then used to elucidate the correlation between the optimized geometries of the coordination spheres of the transition metal atoms and the electronic configurations of these transition metals and the chalcogen atoms.

In this article we describe the synthesis and characterization of [PhTe(tu)2][PhTeI4] and [MesTe(tu)][PhTeX4] (tu = thiourea, X = Br, I), containing multivalent tellurium species. During the syntheses of the compounds, the formation of different species, such as [PhTe(tu)I] or [I(tu)2][PhTeI4] was found, which were isolated and characterized. Thiourea was used in order to explore the relevance of Te···S bonds in the solid state structures of the products compared to related compounds with Te···X and X···X bonds in their molecular structures. Different types of chalcogen-chalcogen, chalcogen-halogen and halogen-halogen interactions are described by the combination of crystallographic data and computational methods. The nature of these interactions was evaluated by the noncovalent interaction index (NCI), and quantum theory of atoms in molecules (QTAIM) analyses.

The compounds [Pd2I2{Te((2,6-OCH3)2C6H3)}2(PCy3)2] (1), [Pd2I2{Te((2,6-OCH3)2C6H3)}2(PR2R')2]∙2CH3CN (2), [Pd2{Te((2,6-OCH3)2C6H3)}2(phen)2][Hg2Br6(phen)2] (3), [Pd2Cl2(TePh2)2(TePh)2] ∙ DMF (4), [Pd2(SePh)2(2,2′-bipy)2][HgBr4]∙2DMF (5), [Pd2(SePh)2-(phen)2][HgI4]∙5DMF (6), [Pd2{Te((2,6-OCH3)2C6H3)}2(phen)2][Hg2I6]-[Hg((2,6-OCH3)2C6H3)2] (7) containing [Pd2(µ-ER)2] core (E = Se, Te; R = aryl) were synthesized and characterized by IR spectroscopy, elemental analysis and X-ray crystallography. Intermolecular metallophilic interactions were evaluated through crystallographic studies combined with Density Functional Theory calculations. The structural stability of 4–7 were investigated taking in account the interactions E⋯E, Pd⋯Pd and Pd⋯Hg between [Pd2(µ-ER)2] cores.