title: Unique two-fold interpenetration of 3D microporous 3d-4f heterometal-organic frameworks (HMOF) based on a rigid ligand.
abstract: Six heterometal-organic frameworks, {[LnCu1.5(BPDC)3(H2O)2].mH2O}n (Ln = Gd (1, m = 4.75), Tb (2, m = 3.75), Eu (3, m = 5), Ho (4, m = 2), Yb (5, m = 2.25), BPDC = 4,4-dicarboxylate-2,2-dipyridine anion), and {[LuCu1.5(BPDC)3(H2O)1.5].2.5H2O}n (6), have been synthesized under hydrothermal conditions. The structure analyses for 1-6 reveal that the six compounds are isomorphous, belonging to the monoclinic system with space group C2/c, and display two-fold interpenetrating 3D frameworks, which are the first examples of d-f heterometal-organic frameworks based on a rigid ligand. These frameworks were further characterized by elemental analyses, TG analysis, PXRD, hydrogen adsorption and variable-temperature magnetic susceptibilities. Interestingly, hydrogen adsorption was significantly observed under the existence of the two-fold interpenetration. Magnetic investigations suggest that the ferromagnetic coupling exists between Gd3+ and Cu2+ in 1, and that the nature of the interaction between Ln3+ and Cu2+ ions in compounds 2, and 4-6 cannot be absolutely determined when MT values are reduced with decreasing temperature.
authors.affiliation: Department of Chemistry, Nankai University, Tianjin 300071, PR China.
authors.forename: Ming
authors.initials: M
authors.lastname: Fang
authors.forename: Bin
authors.initials: B
authors.lastname: Zhao
authors.forename: Ya
authors.initials: Y
authors.lastname: Zuo
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Wei
authors.initials: W
authors.lastname: Shi
authors.forename: Jing
authors.initials: J
authors.lastname: Liang
authors.forename: Peng
authors.initials: P
authors.lastname: Cheng