Synthesis, magnetic behaviour and structural characterization of the alternating hexanuclear copper(II) compound [Cu6(tmen)6(µ-N3)2(µ-C2O4)3(H2O)2][ClO4]4·2H2O (tmen = Me2NCH2CH2NMe2)

Abstract

The compound [Cu₆(tmen)₆(µ-N₃)₂(µ-C₂O₄)₃(H₂O)₂][ClO₄]₄·2H₂O 1 where tmen is N,N,N′,N′-tetramethylethane-1,2-diamine, was synthesized and characterized. Its crystal structure was determined by single-crystal X-ray analysis. The magnetic behaviour was recorded between 300 and 4 K, showing strong antiferromagnetic coupling. The magnetic susceptibility data were fitted by the expression for a dinuclear copper(II) compound giving the parameters J=–289(2)cm^–1, g= 2.03(1). Polycrystalline powder ESR spectra were recorded at variable temperature. The broad room-temperature signal having g= 2.12 vanished at approximately 55 K.