title: A new family of 1D, 2D and 3D frameworks aggregated from Ni5, Ni4 and Ni7 building units: synthesis, structure, and magnetism.
abstract: Three new Ni(ii)-clusters based on a Y-shaped ligand (biphenyl-3,4',5-tricarboxylate, H3BPT), [Ni5(HBPT)4(OH)2(H2O)12]n (), [Ni4(BPT)2(OH)2(H2O)6]n·4nH2O (), and [Ni7(BPT)2(1,4-bib)2(OH)6(HCO2)2]n·3nH2O () (1,4-bib = 1,4-bi(1H-imidazol-1-yl)benzene), have been synthesized under solvothermal conditions. They were studied by infrared spectroscopy (IR), single crystal X-ray diffraction, thermogravimetric analysis (TGA), and magnetochemistry. The complexes contain low nuclear Ni-clusters as building units (BUs). Structurally, in , the cluster BUs of [Ni5(μ3-OH)2](8+) can be viewed as two reverse triangles sharing a common vertex, which are connected by the partially deprotonated μ2-η(1):η(1)-HBPT(2-) forming 1D chains. The BUs of [Ni4(μ3-OH)2](6+) clusters in can be considered as two reverse triangles sharing a common edge and extended by deprotonated μ6-η(1):η(1):η(1):η(1):η(2)-BPT(3-) constructing a 2D framework. The 3D framework of complex consists of a [Ni7(μ3-OH)4(R-COO)7(HCO2)3] cluster BUs with fully deprotonated μ5-η(1):η(1):η(1):η(1):η(1):η(1)-BPT(3-) and 1,4-bib ligands. In addition, TGA reveals that the complexes are stable in the range of 293-548 K. Magnetostructural analyses indicate ferromagnetic coupling of J1 = 1.85(3) and J2 = 2.25(4) cm(-1) in and J = 5.76(6) cm(-1) in , whereas magnetic parameters J1 = -2.64(3), J2 = -23.22(19) and J3 = 12.02(5) cm(-1) indicate an alternating magnetic chain (AF/F) in .
authors.affiliation: Institute of Molecular Science, Key Laboratory of Chemical Biology and Molecular Engineering of the Education Ministry, Shanxi University, Taiyuan, Shanxi 030006, P. R. China. luliping@sxu.edu.cn ssfeng@sxu.edu.cn.
authors.forename: Ya-Hui
authors.initials: YH
authors.lastname: Liu
authors.affiliation: Institute of Molecular Science, Key Laboratory of Chemical Biology and Molecular Engineering of the Education Ministry, Shanxi University, Taiyuan, Shanxi 030006, P. R. China. luliping@sxu.edu.cn ssfeng@sxu.edu.cn.
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Lu
authors.affiliation: Institute of Molecular Science, Key Laboratory of Chemical Biology and Molecular Engineering of the Education Ministry, Shanxi University, Taiyuan, Shanxi 030006, P. R. China. luliping@sxu.edu.cn ssfeng@sxu.edu.cn and Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province, Institute of Molecular Science, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China.
authors.forename: Miao-Li
authors.initials: ML
authors.lastname: Zhu
authors.affiliation: Institute of Molecular Science, Key Laboratory of Chemical Biology and Molecular Engineering of the Education Ministry, Shanxi University, Taiyuan, Shanxi 030006, P. R. China. luliping@sxu.edu.cn ssfeng@sxu.edu.cn and Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province, Institute of Molecular Science, Shanxi University, Taiyuan, Shanxi 030006, People's Republic of China.
authors.forename: Si-Si
authors.initials: SS
authors.lastname: Feng
authors.affiliation: Institute of Molecular Science, Key Laboratory of Chemical Biology and Molecular Engineering of the Education Ministry, Shanxi University, Taiyuan, Shanxi 030006, P. R. China. luliping@sxu.edu.cn ssfeng@sxu.edu.cn.
authors.forename: Feng
authors.initials: F
authors.lastname: Su