New μ-SnTe4 and μ-Sn2Te6 ligands to transition metal: Solvothermal syntheses and characterizations of zinc tellurostannates containing polyamine ligands

• Zinc-tellurostannates were first prepared with iodine ion assistant.
• Novel μ-1κ:2κ-SnTe4, μ3-1κ:2κ:3κ-SnTe4, and μ-1κ:2κ-Sn2Te6 ligands were obtained.
• The Zinc tellurostannates exhibit optical bandgaps between 1.47 and 1.98 eV.

Zinc tellurostannates [{Zn(teta)}2(μ-1κ:2κ-SnTe4)] (1), [{Zn(teta)}3(μ3-1κ:2κ:3κ-SnTe4)]I2 (2), [{Zn(tren)}2(μ-1κ:2κ-Sn2Te6)] (3), and [Zn(dien)2]4(Sn2Te6)1.75(Sn2Te8)0.25·dien (4) were prepared by the reactions of Zn, Sn, and Te with iodine ion assistant in teta and dien. The tetrahedral [SnTe4]4− anion coordinates to two [Zn(teta)]2+ units as a bidentate μ-1κ:2κ-SnTe4 ligand to form the neutral complex 1. It coordinates to three [Zn(teta)]2+ units with a tridentate μ3-1κ:2κ:3κ coordination modes, generating a complex cation [{Zn(teta)}3(μ3-1κ:2κ:3κ- SnTe4)]2+ in 2. In 3, the [Sn2Te6]4− anion joins two [Zn(tren)]2+cations with the trans terminal Te atoms, forming neutral complex 3. The μ-1κ:2κ-SnTe4, μ3-1κ:2κ:3κ-SnTe4, and μ-1κ:2κ-Sn2Te6 ligands to TM centers in 1–3 have not been observed before. Compound 4 contains a normal [Sn2Te6]4− and an abnormal [(Sn2Te6)0.75(Sn2Te8)0.25]4− anions. Compounds 1–4 exhibit narrow band gaps in the range of 1.47–1.98 eV, and a distinct red-shift of the band gaps is observed from 4 to 1−3.

Zinc tellurostannates were prepared with iodine ion assistant in polyamines, and first μ-1κ:2κ-SnTe4, μ3-1κ:2κ:3κ-SnTe4, and μ-1κ:2κ-Sn2Te6 ligands TM centers were obtained.Figure optionsDownload as PowerPoint slide