Layered copper compounds based on 4-(3-bromothienyl)phosphonate (BTP): weak ferromagnetism observed in [Cu2(4,4′-bpy)0.5(BTP)2]·H2O
作者:Li-Rong Guo、Feng Zhu、Yu Chen、Yi-Zhi Li、Li-Min Zheng
DOI:10.1039/b907356f
日期:——
Two copper phosphonates based on 4-(3-bromothienyl)phosphonic acid (BTPH2) with formula Cu(H2O)(BTP) (1) and [Cu2(4,4â²-bpy)0.5(BTP)2]·H2O (2) are reported. Compound 1 has a layered structure in which dimers of Cu2O2}, made up of edge-sharing CuO6} octahedra, are bridged by both the PO3C} tetrahedra through corner-sharing and the water molecules. Compound 2 exhibits a novel layered structure where the Cu2(BTP)2} columns, containing Cu4O6} tetrameric cores and OâPâO linkages, are connected by 4,4â²-bipyridine. In both cases, the 3-bromothienyl groups are grafted on the two sides of the layers. Magnetic studies reveal that antiferromagnetic interactions are mediated between the Cu(II) centers in 1, while for 2, weak ferromagnetism resulted from spin canting is observed. Electrochemical properties of compounds 1â2 are also investigated.
报告了两种基于 4-(3-溴噻吩基)膦酸 (BTPH2) 的膦酸铜,其化学式分别为 Cu(H2O)(BTP) (1) 和 [Cu2(4,4â²-bpy)0.5(BTP)2]Â-H2O (2)。化合物 1 具有层状结构,其中Cu2O2}的二聚体(由边共享的CuO6}八面体组成)通过角共享和水分子被PO3C}四面体桥接。化合物 2 显示出一种新颖的层状结构,其中Cu2(BTP)2}柱含有Cu4O6}四元核心和 OâPâO 链接,并由 4,4â²-联吡啶连接。在这两种情况下,3-溴噻吩基团都接枝在层的两侧。磁性研究表明,1 中的 Cu(II)中心之间存在反铁磁性相互作用,而 2 中则存在自旋悬臂作用产生的弱铁磁性。此外,还研究了化合物 1â2 的电化学特性。