A novel Cu(II)-W(v) bimetallic assembly magnet {[Cu(en)_2]_2[(W(CN)_8]_2centre dotH_2O}infinity (en=ethylenediamine) with cube-like W_8Cu_(12) units from a coordinated anion template self-assembly reaction

摘要

A novel molecular-based magnet of three-dimensional(3-D) cyanide-bridged bimetallic assemble,{[Cu(en)_2]_2[W(CN)_8)_2centre dotH_2O}_infinity (1),where en-ethylenediamine,was synthesized and structurally characterized.The assembly has a three-dimensiona lnetwork structure extended by three kinds of Cu~(II)-NC-W~v-CN-Cu~(II) linkages wtih very longaxialCu-N-(cyanide) interactions due toJahn-Teller effects.The network is based on a W_8Cu_(12) cube-like unit witheight [W(CN)_8]~(3-) anions at the corners of thedistorted cube and twelve [Cu(en)_2]~(2+) cations at the middle of theedges,in whciha coordination anion [W_8Cu_(12) cube.Magnetic studies reveal tat the complex dispalys 3-D ferromagnetic ordering over the latice below the Curie temperature at around 2 K.