Systematic Investigation of Lanthanide Phosphonatoethanesulfonate Framework Structures by High-Throughput Methods, Ln(O3P-C2H4-SO3)(H2O) (Ln = La

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• 作者：Andreas Sonnauer ; Christian Nä ; ther ; Henning A. H&ouml ; ppe ; Jü ; rgen Senker ; Norbert Stock
• 刊名：Inorganic Chemistry
• 出版年：2007
• 出版时间：November 12, 2007
• 年：2007
• 卷：46
• 期：23
• 页码：9968 - 9974
• 全文大小：574K
• 年卷期：v.46,no.23(November 12, 2007)
• ISSN：1520-510X

文摘

Following the strategy of using polyfunctional phosphonic acids for the synthesis of new metal phosphonates, theflexible organic linker molecule 2-phosphonoethanesulfonic acid, H₂O₃P-C₂H₄-SO₃H (H₃L), was used in a high-throughput (HT) investigation of lanthanide phosphonatoethanesulfonates. Two HT experiments comprising 96individual hydrothermal reactions were performed to systematically investigate the influence of pH, rare earth ion,molar ratio of Ln³⁺:H₃L, and the counterion in the system LnX₃/H₃L/NaOH/H₂O with X = NO₃^-, Cl^-, and CH₃COO^-.Whereas under basic conditions Ln(OH)₃ is formed, acidic reaction conditions lead to nine isotypic compoundsLn(O₃P-C₂H₄-SO₃)(H₂O) with Ln = La (1), Ce (2), Pr (3), Nd (4), Sm (5), Eu (6), Gd (7), Tb (8), and Dy (9). Thecrystal size of the compounds is strongly dependent on the ionic radius of the lanthanides and the pH. No significantinfluence of the counterions of the rare earth salts is observed. For compounds 1, 2, 4, and 5 the crystal structurescould be determined from single-crystal X-ray diffraction. The structures are built up from chains of edge-sharingLnO₈ polyhedra that are connected by the phosphonate and sulfonate groups to layers. These layers are linked bythe -CH₂CH₂- group to a three-dimensional framework. The compounds 6 and 8 display luminescence in thevisible range (intensity maximum 612 and 544 nm, respectively). Thermogravimetric investigations and temperature-dependent X-ray powder diffraction demonstrate the stability of the crystal structure up to 270 C. Furthermore IR,Raman, and solid-state MAS NMR spectra of 1 and magnetic property measurements of 7 are also presented.