Synthesis, structure and magnetic behaviour of a two-dimensional cyano-bridged complex [{Cu(ept)}3Fe(CN)6](ClO4)2·5H2O [ept = N-(2-aminoethyl)-1,3-diaminopropane]

Abstract

The bimetallic compound [{Cu(ept)}₃Fe(CN)₆](ClO₄)₂·5H₂O [ept =  N-(2-aminoethyl)-1,3-diaminopropane] has been prepared from the reaction of Cu(ClO₄)₂·6H₂O, ept and K₄[Fe(CN)₆]·3H₂O in water and its crystal and molecular structure has been determined. The structure consists of a two-dimensional network formed by [{Cu(ept)}₃Fe(CN)₆]²⁺ moieties, perchlorate anions and water molecules. Every [Fe(CN)₆]⁴⁻ anion is coordinated by six [Cu(ept)]²⁺ cations through six cyano nitrogens, providing a 2D sheet structure extended by Fe–(CN)–Cu linkages. All the copper(II) ions are five-coordinated by three ept nitrogen and two cyanide nitrogen atoms in a distorted square-pyramidal arrangement. The EPR spectrum of the compound at room temperature also confirms the coordination environment of the copper(II) atoms. A magnetic susceptibility measurement of the complex was performed down to 4 K but no coupling was found among the copper atoms ia the –(NC)–Fe–(CN)– bridges.