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论文类型：期刊论文

发表时间：2013-08-01

发表刊物：CRYSTAL GROWTH & DESIGN

收录刊物：SCIE、EI、Scopus

卷号：13

期号：8

页面范围：3429-3437

ISSN号：1528-7483

摘要：The syntheses, structures, and characterization of three series of one-dimensional (1D) and three-dimensional (3D) 3d-4f duster-based polymers with AA (HGly or HAla) and formate as mixed ligands are described. Under the pH values of 6.0 and 5.2, respectively, three ID undulating chains [Ln = Gd, (1); Tb, (2); and Dy(3)] and two 3D frameworks [Ln = Gd, (4) and Tb, (5)] with a 3-connected pcu-h network were obtained. Both of them use Gly-based heptanuclear trigonal prism [LnCu(6)] clusters and mononuclear Ln(3+) as nodes linked by syn-anti formate ligands. Moreover, three 3D polymers [Ln = Gd, (6); Tb, (7); and Dy (8)] with a 6-connected pcu network were built from Ala-based [Ln(6)Cu(24)] clusters and formate bridges. The formate ligand played an important role not only for the construction of the cluster units but also for their further linkage to extended arrays. Magnetic analyses indicate the three Gd3+-containing compounds bear an interesting magnetocaloric effect, and the -Delta Sm(T) values are 5.8, 6.0, and 18.8 J kg(1-) K-1 (Delta H = 5 T) for 1, 4, and 6, respectively.