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Updated: Jan 3, 2026

Synthesis of Nine-atom Deltahedral Zintl Ions of Germanium and their Functionalization with Organic Groups
Published on: February 11, 2012
2-Picolinate-Decorated Iron-Lanthanide Heterometallic Germanotungstates Including an S-Shaped [Ge2W20O72]16- Segment
Jun Jiang1, Yanhong Chen1, Lulu Liu1
1Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Chemical Engineering , Henan University , Kaifeng , Henan 475004 , People's Republic of China.
Abstract:
A series of neoteric 2-picolinate (pic)-decorated iron-lanthanide (Ln)-embedded germanotungstates (GTs), [LnIII(H2O)8]2H2[Fe4(H2O)4v(pic)4Ge2W20O72]·34 H2O [Ln = La (1), Ce (2), Nd (3), Sm (4), Gd (5), Tb (6), Dy (7), Er (8), Tm (9)] and [Eu(H2O)8]2H2[Fe4(H2O)4(pic)4Ge2W20O72]·36H2O (10; Hpic = picolinic acid), were hydrothermally prepared. The polyoxoanions of 1-10 possess a quadri-FeIII-inserted [Fe4(H2O)4(pic)4Ge2W20O72]8- subunit with bisupporting [Ln(H2O)8]3+ cations. The quadri-FeIII-inserted [Fe4(H2O)4 (pic)4Ge2W20O72]8- subunit can be described as a particular S-shaped [Ge2W20O72]16- segment functionalized by four [Fe(H2O)(pic)]2+ cations. It should be pointed out that the carboxyl O and pyridine N atoms on pic ligands simultaneously coordinate with Fe3+ cations in a five-membered heterocyclic mode, which can enhance the stability of the structures. Moreover, fluorescent measurements of 3, 4, 6, and 10 were made, manifesting that fluorescent emissions primarily stem from Ln3+ ions. With regard to 10, energy transfer (ET) from GT and pic groups to Eu3+ centers was intensively studied. In addition, the magnetic susceptibility properties of 7 and 10 were studied.
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