Five dimeric thiogermanates with transition metal complexes of multidentate chelating amines: Syntheses, structures, magnetism and photoluminescence

One-Dimensional Vanadium(III) Chalcogenidostannates Incorporating [V(tepa)]3+ Complexes as Bridging Groups

Two new one-dimensional (1D) vanadium(III) chalcogenidostannates, [H₂tepa]_0.5n[V^III(tepa)(μ-Sn₂Q₆)]_n [Q = S (1), Se (2); tepa = tetraethylenepentamine], were achieved by solvothermal methods, which offer the first examples of organic hybrid polymeric chalcogenidostannates incorporating [V(tepa)]³⁺ complexes as bridging groups. Both 1 and 2 feature the 1D sinusoidal chains of [V^III(tepa)(μ-Sn₂Q₆)]_n containing two types of novel bridging modes of the [μ-Sn₂Q₆]^4- anion. Their magnetic, photocurrent response, and optical properties are also studied.

Stepwise Conversion from GeO2 to [MGe4S10]n3n- (M = Cu, Ag) Polymer via Isolatable [Ge2S6]4- and [Ge4S10]4- Anions by Virtue of Templating Technique

Rational synthesis of inorganic matter remains a great challenge encountered with modern synthetic chemistry. Here we reported the stepwise solvothermal conversion from GeO₂ to [MGe₄S₁₀]_n^3n- (M = Cu, Ag) polymer via isolatable [Ge₂S₆]^4- and [Ge₄S₁₀]^4- anions by virtue of templating technique. The facile sulfuration of GeO₂ resulted in the methylammonium-templated dimeric thiogermanate [CH₃NH₃]₄Ge₂S₆ (1). This was used subsequently as a precursor for the formation of adamantane-like [Ge₄S₁₀]^4- cluster, which was isolated as a mixed methylammonium/ethylammonium salt [CH₃CH₂NH₃]₃[CH₃NH₃]Ge₄S₁₀ (2). Compound 2 was then successfully used as a precursor to react with Cu⁺ and Ag⁺ cations in the presence of tetraethylammonium, resulting in alternating copolymeric products [(CH₃CH₂)₄N]₃MGe₄S₁₀ (M = Cu (3), Ag (4)), whose anionic moieties feature a novel zigzag chainlike structure constructed by [Ge₄S₁₀]^4- clusters via two-coordinate Cu⁺/Ag⁺ linkers. Mixed amine/ethanol or deep eutectic solvents were applied as media for the syntheses of 1-4, and all the products were characterized in the solid state and solution. Crystal structural analysis of the title compounds revealed significant templating roles of the alkylammonium cations as both space-filling agents and hydrogen-bonding donors, suggesting the structure-directing mechanism for the species formation and crystal growth. The design and optimization of multistep structural conversion upon templating effects would be beneficial for drawing rational, predictable pathways for inorganic synthesis.

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.

A comparison study of aliphatic and aromatic structure directing agents influencing the crystal and electronic structures, and properties of iodoplumbate hybrids: water induced structure conversion and visible light photocatalytic properties

The introduction of the aliphatic amines en (ethylenediamine), aep (N-(2-aminoethyl)piperazine) and tepa (tetraethylenepentamine), and the aromatic species 2,2'-bipy (2,2'-bipyridine) and dpe (1,2-di(4-pyridyl)ethylene) as structure directing agents (SDAs) into inorganic iodoplumbates affords six hybrids, namely [(Hen)4(H2.5O)2I](PbI6) (1), Cs2n[Pb3I8(en)2]n (2), (H3tepa)n(PbI5)n (3), (H2aep)n(PbI4)n (4), (Et22,2'-bipy)n(Pb2I6)n (5) and (Et2dpe)n(Pb2I6)n (6). 1 contains a discrete octahedral (PbI6)(4-) anion generated under the direction of a novel co-template, [(Hen)4(H2.5O)2I](4+). 2 contains inorganic Cs(+) ions and a novel hybrid anionic layer [Pb3I8(en)2]n(2n-) that has never been encountered in iodoplumbate hybrids. 3 features a zigzag (PbI5)(3-) chain with the charge being compensated by a triprotonated tepa cation. 4 is composed of perovskite sheets of lead(ii) octahedra and aep cations that are generated from tepa via an unprecedented in situ ligand reaction. Both 5 and 6 have (Pb2I6)n(2n-) chains and represent the first example of introducing a 2,2'-bipy or dpe derivative cation in iodoplumbate hybrids, respectively. The comparative study reveals that aliphatic amines and aromatic species contribute differently to the crystal and electronic structures, and the properties of the hybrids. Importantly, 1-4 exhibit interesting water induced structure conversions, while 5 and 6 can be used as heterogeneous photocatalysts for dye wastewater treatment under visible light irradiation.

Novel thioarsenates {[Mn(2,2'-bipy)2(SCN)][Mn(2,2'-bipy)](As(V)S4)}2 and {[Mn(2,2'-bipy)2(SCN)]2[As(III)2(S2)2S2]}: introducing an anionic second ligand to modify MnII complex cations of 2,2'-bipyridine

Two novel manganese thioarsenates, {[Mn(2,2'-bipy)2(SCN)][Mn(2,2'-bipy)](As(V)S4)}2 (1, 2,2'-bipy = 2,2'-bipyridine) and {[Mn(2,2'-bipy)2(SCN)]2[As(III)2(S2)2S2]} (2), containing thiocyanate-modified Mn-2,2'-bipy complex cations were synthesized. They feature two terminal [Mn(2,2'-bipy)2(SCN)](+) complex cations bridged by a polyanion {[Mn(2,2'-bipy)]2(As(V)S4)2}(2-) for 1 and a cyclic thioarsenate anion (As(III)2S6)(2-) for 2. In 2, the [As(III)2(S2)2S2](2-) anion can be described as two (As(III)S3)(3-) trigonal-pyramids interlinked through S-S bonds. The method to obtain new metal complex cations shown here, introducing an anionic second ligand to modify the number of coordination sites and the charges of the metal complex cations simultaneously, is different from the traditional methods, varying either the TM center or the organic ligand or employing mixed neutral organic ligands, and may open up a new route for preparing novel chalcogenidometalates. Compounds 1 and 2 exhibit wide optical gaps of 2.20 and 2.67 eV, respectively, and photoluminescence with the emission maxima occurring around 440 nm. Magnetic measurements show the presence of antiferromagnetic interactions between Mn(II) centers in the two compounds.