The First Tetradentate μ-1κ2:2κ2-Sn2Se6Ligand to a Lanthanide(III) Center: Solvothermal Syntheses and Characterizations of Lanthanide Selenidostannate Polymers with Tetraethylenepentamine as a Second Ligand

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 novel 2-D Mn selenidostannate(iv) incorporating high-nuclear Mn clusters with spin canting behavior

A solvothermal reaction of SnCl₄·5H₂O, Mn and Se in ethanolamine (Hea) yielded a novel 2-D Mn selenidostannate(iv) [Mn₇(ea)₆(SnSe₄)₂]_n (1), which not only provides the first example of the incorporation of a hepta-nuclear Mn cluster [Mn₇(ea)₆]⁸⁺ into a selenidostannate(iv) framework, but also shows unusual spin canting behavior.

Lanthanide(III) complexes with μ-SnSe4 and μ-Sn2Se6 linkers: solvothermal syntheses and properties of new Ln(III) selenidostannates decorated with linear polyamine

New lanthanide-selenidostannate complexes [{La(peha)(Cl)}{La(peha)(NO3)}(μ-1κ2:2κ2-SnSe4)] (1), [H2trien][{La(trien)2}2(μ-1κ:2κ-Sn2Se6)][Sn2Se6]·H2O (2) and [{Ln(tepa)(μ-OH)}2(μ-1κ:2κ-Sn2Se6)] n ·nH2O (Ln=Sm(3), Eu(4)) were prepared by solvothermal methods in pentaethylenehexamine (peha), triethylenetetramine (trien) and tetraethylenepentamine (tepa), respectively. Acting as a tetradentate chelating and bridging ligand, μ-1κ2:2κ2-SnSe4, the tetrahedral SnSe4 unit joins {La(peha)(Cl)}2+ and {La(peha)(NO3)}2+ complex fragments to generate the neutral coordination compound 1. The tetradentate μ-1κ2:2κ2 bridge in 1 represents a new coordination mode for the SnSe4 tetrahedron. In 2, dinuclear [Sn2Se6]4− anions are formed of SnSe4 tetrahedra via edge-sharing. One [Sn2Se6]4− anion acts as a bidentate bridging ligand in a μ-1κ:2κ coordination mode to join two {La(trien)2}3+ units, and the other [Sn2Se6]4− anion exists as a free charge compensating ion. In 3 and 4, the [Sn2Se6]4− anion connects binuclear [{Ln(tepa)(μ-OH)}2]2+ (Ln=Sm, Eu) units with a bidentate μ-1κ:2κ mode, giving neutral coordination polymers [{Ln(tepa)(μ-OH)}2(μ-1κ:2κ-Sn2Se6)] n . The La(2)3+ ion in 1 is in a 10-fold coordination environment of LaN6O2Se2, whereas the La(1)3+ ions in 1 and 2 are in 9-fold coordinated environments forming polyhedra LaN6ClSe2 and LaN8Se, respectively. The Sm3+ and Eu3+ ions in 3 and 4 are both in an 8-fold coordination environment of LnN5O2Se. Compounds 1−4 exhibit optical band gaps between 2.21 and 2.42 eV. Their thermal stabilities were investigated by thermogravimetric analyses.

Two types of lanthanide selenidostannates(IV) first prepared under the same solvothermal conditions

Two types of lanthanide selenidostannates(iv) [Ln2(tepa)2(μ-OH)2Sn2Se6] {Ln = Y(), Pr (), Dy (), Er (), Tm (); tepa = tetraethylenepentamine} and [Ln2(tepa)2(μ2-OH)2Cl2]2[Sn4Se10]·4H2O {Ln = Y (), Dy (), Er (), Tm ()} have been synthesized under identical solvothermal conditions and characterized structurally. Type I (, , , and ) displays 1-D neutral chains [Ln2(tepa)2(μ-OH)2Sn2Se6]n, while type II (, , and ) contains discrete adamantane-like [Sn4Se10](4-) ions with binuclear lanthanide complex [Ln2(tepa)2(μ-OH)2Cl2](2+) ions as counterions. Although the solvothermal synthetic methods could result in the formation of various transition-metal chalcogenidometalates, such identical experimental conditions usually result in the only stable phases of lanthanide chalcogenidometalates. Hence, two different lanthanide selenidostannates(iv), obtained under same solvothermal conditions and starting materials, have been first observed in this work. The optical properties of all the compounds have been investigated by UV-vis spectra.