Solvothermal Syntheses and Characterization of New Transition Metal Chalcogenidogermanates [{Co(tepa)}2(μ-Ge2S6)] and [{M(tepa)}2(μ-Ge2Se6)] (M = Mn, Fe) (tepa = Tetraethylenepentamine)

A series of new hybrid chalcogenogermanates: the rare examples of chalcogenogermanates combined with trivalent vanadium complexes

A series of new hybrid chalcogenogermanates [Mn₂(en)₄Ge₂S₆]_n (1, en = ethylenediamine), [Mn₂(dap)₄Ge₂S₆]_n (2, dap = 1,2-diaminopropane), [H₂dien]_n[MnGeS₄]_n (3, dien = diethylenetriamine), [V(en)₂(ea)]₂[Ge₂Se₆] (4, Hea = ethanolamine), [V(teta)(ea)]₂[Ge₂Se₆] (5, teta = triethylenetetramine) and [V₂(en)₆(μ-O)][Ge₂Se₆] (6) were solvothermally synthesized and structurally characterized. Both 1 and 2 contain dimeric [Ge₂S₆]^4- anions and [Mn(en)₂]²⁺/[Mn(dap)₂]²⁺ complex cations, which are interconnected to generate 1-D neutral chain-like structures [Mn₂(en)₄Ge₂S₆]_n and [Mn₂(dap)₄Ge₂S₆]_n, respectively. 3 consists of a protonated H₂dien²⁺ cation and a 1-D straight chain built from [MnS₄] and [GeS₄] tetrahedra sharing opposite edges, and is the only example of a chelating amine uncoordinated to a transition metal ion. Both 4 and 5 consist of [Ge₂Se₆]^4- anions constructed by two [GeSe₄] tetrahedra sharing a common edge and discrete complex cations [V(en)₂(ea)]²⁺/[V(teta)(ea)]²⁺. 6 is composed of a [Ge₂Se₆]^4- anion and dinuclear complex cation [V₂(en)₆(μ-O)]⁴⁺ containing an en molecule as a rare monodentate ligand. Although some selenidogermanates with transition metal complexes have been successfully prepared, no selenidogermanates with trivalent vanadium complexes have been documented. Therefore, 4-6 offer the first examples of selenidogermanates with trivalent vanadium complexes under solvothermal conditions. Their optical and photocurrent response properties were studied.

A Series of Lanthanide Selenidogermanates: The First Coexistence of Three Types of Selenidogermanate Units in the Same Architecture

A series of lanthanide selenidogermanates, (H₂peha)[Ln₂(μ-OH)₂(tepa)₂Cl₂]{[Ln₂(μ-OH)₂(tepa)₂Cl]₂(μ-Ge₂Se₆)}[Ge₂Se₆]Cl₂ [Ln = Y (1a) and Er (1b); peha = pentaethylenexamine, tepa = tetraethylenepentamine], [Sm₂(μ-OH)₂(tepa)₂(μ-Ge₂Se₆)]_n (2), [Ho₂(μ-OH)₂(tepa)₂(μ-Ge₂Se₆)]_n (3), and [Ce₄(tepa)₄(μ-GeSe₄)(μ-GeSe₅)(μ-Ge₂Se₆)]_n (4), were made under solvothermal conditions. Compounds 1a and 1b contain a protonated H₂peha²⁺ ion, the complex cation [Ln₂(μ-OH)₂(tepa)₂Cl₂]²⁺, a [Ge₂Se₆]^4- anion, free Cl^- ions, and a {[Ln₂(μ-OH)₂(tepa)₂Cl]₂(μ-Ge₂Se₆)}²⁺ cation constructed by two unsaturated [Ln₂(μ-OH)₂(tepa)₂Cl]³⁺ groups connecting via the trans terminal Se atoms of the [Ge₂Se₆]^4- anion, which provides the first example of an organic decorated lanthanide selenidogermanate cation. Both compounds 2 and 3 contain one-dimensional chains [Ln₂(μ-OH)₂(tepa)₂(μ-Ge₂Se₆)]_n constructed by a combination of unsaturated complex cations [Ln₂(μ-OH)₂(tepa)₂]⁴⁺ and [Ge₂Se₆]^4- anions, but their stacking patterns of neutral chains are different. Compound 4 contains one-dimensional chain [Ce₄(tepa)₄(μ-GeSe₄)(μ-GeSe₅)(μ-Ge₂Se₆)]_n, where three different selenidogermanate units acting as bridging ligands connect unsaturated [Ce(tepa)]³⁺ ions. Compound 4 represents the first example of the coexistence of three different selenidogermanate anions in the same architecture. Their optical properties are studied, and the magnetic properties of compounds 1b and 2-4 are also investigated.