A Series of Lanthanide Coordination Polymers Based on Designed Bifunctional 1,4-Bis(imidazol-1-yl)terephthalic Acid Ligand: Structural Diversities, Luminescence, and Magnetic Properties

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• 作者：Xiu-Tang Zhang ; Li-Ming Fan ; Wei-Liu Fan ; Bin Li ; Guang-Zeng Liu ; Xin-Zheng Liu ; Xian Zhao
• 刊名：Crystal Growth & Design
• 出版年：2016
• 出版时间：July 6, 2016
• 年：2016
• 卷：16
• 期：7
• 页码：3993-4004
• 全文大小：1100K
• 年卷期：0
• ISSN：1528-7505

文摘

On the basis of the designed bifunctional 1,4-bis(imidazol-1-yl)terephthalic acid (H₂BTA) ligand, a series of three-dimensional lanthanide coordination polymers, namely, [La₂(BTA)_1.5(ox)_1.5(H₂O)₃]_n (1), [Nd(BTA)(ox)_0.5(H₂O)]_n (2), {[Ln(HBTA)(ox)(H₂O)]·xH₂O}_n (Ln = Pr for 3 (x = 0), Sm for 4 (x = 0), Dy for 5 (x = 1.5), and Eu for 6 (x = 1)), and [Ln(BTA)(SO₄)_0.5(H₂O)]_n (Ln = Eu for 7, and Tb for 8) were obtained with the help of oxalate or sulfate ions. On the basis of the binuclear La2 secondary building unit (SBUs), the framework of 1 displays an unprecedented (3,3,4,9)-connected net with the point symbol of (4¹¹.5⁵.6¹⁴.7⁵.8)₂(4².5)₂(4³)₂(4⁴.6²). While in complex 2, the binuclear Nd2 SBUs are connected by the BTA^2– ligands to generate an interestingly (4,10)-connected (4¹².5¹⁶.6¹².7⁵)(4⁶)₂ net. Complexes 3–6 are isomorphism and show a 2-fold interpenetrated 4-connected (6⁶)-dia net. Complexes 7 and 8 are isomorphism and show a novel (4,5)-connected (4⁴.6²)(4⁴.6⁶) net. Photoluminescence investigations show that 2 is a good near-infrared luminescent material, and 4 is a rarely reported single component white light emitting material. Complexes 6 and 7 show typically red emission, while complex 8 shows typically green emission, which can be used as a red or green emitting phosphor. Moreover, the luminescent lifetimes and quantum yields of the titled complexes were investigated. The magnetic susceptibility data of 2 indicated there are antiferromagnetic interactions between the Nd^III ions.