STRUCTURALLY ALTERNATING COPPER(II) CHAINS FROM OXALATE AND AZIDE BRIDGING LIGANDS - SYNTHESES AND CRYSTAL-STRUCTURE OF [CU-2(MU-OX)-(DEEN)(2)(H2O)2(CLO4)(2)] AND [(CU-2(MU-N-3)(MU-OX)(DEEN)(2))(N)][CLO4](N) (DEEN EQUALS ET(2)NCH(2)CH(2)NH(2))

The mu-oxalato dinuclear compound [Cu-2(mu-ox)(deen)(2)(H2O)(2)(ClO4)( 2)] 1 and the derived alternating mu-oxalato-mu-azido chain [{Cu-2(mu- N-3)(mu-ox)(deen)(2)}(n)][ClO4](n) 2, where deen = N,N-diethylethane-1 ,2-diamine, have been synthesized and characterised. The crystal struc tures of 1 and 2 have been determined by single-crystal X-ray analysis . Their magnetic behaviour has been recorded between 300 and 4 K, show ing strong antiferromagnetic coupling in each case. The data were fitt ed by the expression for a dinuclear copper(II) compound giving the pa rameters J = -300(3) cm(-1), g = 2.15(1) for 1 and J = -287(1) cm(-1), g = 2.28(1) for 2.