Syntheses, magnetic properties, and crystal structures of the dimers [LNi(µ-N3)3NiL](ClO4) and [L′2Ni2(N3)2(µ-N3)2](L =N,N′,N″-trimethyl-1,4,7-triazacyclononane; L′= 1,5,9-triazacyclododecane); µ-triazido-vs. µ-diazido-bridging

Abstract
The complexes [L2Ni2(µ-N3)3(ClO4)(1), [L2Ni2(N3)2(µ-N3)2](2), and [L′2Ni2(N3)2(µ-N2)](3) where L and L′ represent the cyclic triamines N,N,′N′-trimethyl-1,4,7-triazaclonane and 1,5,9-triazacyclododecane, have been synthesized and characterization of (1) and (3) by X-ray crystallography showed that (1) contains three end-to-end co-ordinated µ-azido bridges, whereas (3) contains only two µ-azido bridges and two monodentate N3-ligands; the nickel centres in (1),(3) are strongly antiferromagnerically coupled.