Polymorphic Graphene-like Cuprous Germanosulfides with a High Cu-to-Ge Ratio and Low Band Gap

Syntheses, structures, and photocatalytic properties of open-framework Ag-Sn-S compounds

Four open-framework Ag-Sn-S compounds K2Ag2Sn2S6 (1); K2Ag2SnS4 (2); Rb2Ag2SnS4 (3); and Cs2Ag2SnS4 (4) have been synthesized using a solvothermal method. Compound 1 possesses a unique three-dimensional (3D) structure in which Ag+ ions are two-coordinated. Compounds 2-4 have the same layered structure in which Ag+ ions are tetrahedrally coordinated. Photocatalytic degradation properties of methylene blue have been investigated and compound 1 displays excellent photodegradation activities. The photoelectric response properties, optical properties, and theoretical calculations of these compounds have also been studied.

Cotemplating Assembly and Structural Variation of Three-Dimensional Open-Framework Sulfides

Open-framework sulfides (H₃O)KCu₆Ge₂S₈ (1) and (H₃O)RbCu₆Ge₂S₈ (2) were prepared by a cotemplating strategy. This shows that alkali-metal and protonated water cations act as cotemplates to direct the three-dimensional open-framework sulfides. These templates direct two types of one-dimensional channels that arrange parallelly, and different types of templates reside in different types of channels. By introduction of the Cs cation into the synthetic systems of 1 and 2, (H₃O)K_0.6Cs_0.4Cu₆Ge₂S₈ (3) and (H₃O)Rb_0.75Cs_0.25Cu₆Ge₂S₈ (4) were obtained. Compound 3 has a different anionic framework from those of 1 and 2, while 4 is isostructural with 1 and 2.

Linear Copper Complex Arrays as Versatile Molecular Strings: Syntheses, Structures, Luminescence, and Magnetism

The defined linear arrangement of metal atoms in discrete coordination complexes or polymers is still one of the most intriguing challenges in synthetic chemistry. These chain arrangements are of fundamental importance, because of their potential applications as molecular wires and single molecule magnets (SMM) in microelectronic devices on a molecular scale. Oligonuclear Group 11 metal complexes with suitable bridging ligands, specifically those that are based on copper as the first choice of a cheap precursor coinage metal, are of particular interest in this regard. This is due to the superior luminescence properties of these linear clusters that often show d¹⁰ ⋅⋅⋅d¹⁰ interactions in their molecular structures. The combination of Cu^I with heavier coinage metal ions results in tunable emissive arrays that are also stimuli-responsive. Thus, both linear multinuclear Cu^I and linear heteropolymetallic Cu^I /Ag^I as well as Cu^I /Au^I clusters are excellent candidates for applications in molecular/organic light-emitting devices (OLEDs). Alternatively, paramagnetic multinuclear cupric arrays are prominent as potential molecular wires with enhanced magnetic properties through multiple coupled d⁹ centers. This Review covers the whole range of linear multinuclear assemblies of cuprous and cupric ions in complexes and coordination polymers, their syntheses, photophysical behavior, and magnetic properties. Moreover, recent advances in the rapidly progressing field of hetero-Cu^I /Ag^I and Cu^I /Au^I molecular strings are also discussed.

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 series of new manganese thioarsenates(v) based on different unsaturated [Mn(amine)x]2+complexes

Different unsaturated [Mn(amine)_x]²⁺complexes have a significant structure directing effect on the structures of manganese thioarsenates(v) under similar solvothermal conditions.