title: Diverse self-assembly from predesigned conformationally flexible pentanuclear clusters observed in a ternary copper(II)-triazolate-sulfoisophthalate system: synthesis, structure, and magnetism.
abstract: Self-assembly from the predesigned Cu(II)5 secondary building unit (SBU) in the ternary Cu(II)-triazolate-sulfoisophthalate system generates three interesting magnetic samples: an open pillared-layer framework with nanosized Cu(II)30 metallamacrocycle-based sublayer (1), a (3,6)-connected 2-fold interpenetrating network consisting of alternating Cu(II)5 and Cu(II)1 cores (2), and a (4,8)-connected architecture constructed from centrosymmetric Cu(II)7 clusters and four-branched 5-sulfoisophthalate (sip(3-)) connectors (3). These various structures significantly result from the variable connectivity and the slight expansion of the predetermined conformationally flexible Cu(II)5 SBUs. Furthermore, these intriguing structural motifs in 1-3 essentially induce different magnetic phenomena. A field-dependent metamagnetic transition from antiferromagnetic ordering to weak ferromagnetism is observed in the frustrated Cu(II)30-based sublayer of 1. The paramagnetic Cu(II)1 core in 2 virtually contributes to an S = (1)/2 spin ground state due to the completely compensated magnetic moment in the 1,2,3-triazolate (ta(-))-bridged Cu(II)5 cluster containing ribbon. In contrast, strong antiferromagnetic interactions in the locally centrosymmetric Cu(II)7 cluster lead to an overall S = (1)/2 spin ground state of 3. Thus, the SBU-derived self-assembly strategy provides important hints for polymetallic cluster based high-dimensional magnetic materials, which also brings a new vision for the design and construction of novel functional materials.
authors: College of Chemistry, Key Laboratory of Inorganic-Organic Hybrid Functional Material Chemistry, Ministry of Education, Tianjin Key Laboratory of Structure and Performance for Functional Molecules, Tianjin Normal University , Tianjin 300387, People's Republic of China.
authors: En-Cui
authors: EC
authors: Yang
authors: Yuan-Yuan
authors: YY
authors: Zhang
authors: Zhong-Yi
authors: ZY
authors: Liu
authors: Xiao-Jun
authors: XJ
authors: Zhao