A series of Cu(II)-azide polymers of Cu6 building units and the role of chelating diamine in controlling their dimensionality: synthesis, structures, and magnetic behavior

Inorg Chem. 2010 Nov 15;49(22):10658-67. doi: 10.1021/ic1016966. Epub 2010 Oct 19.

Abstract

Four new neutral copper-azido polymers [Cu(6)(N(3))(12)(aem)(2)](n)(1), [Cu(6)(N(3))(12)(dmeen)(2)(H(2)O)(2)](n) (2), [Cu(6)(N(3))(12)(N,N'-dmen)(2)](n) (3), and [Cu(6)(N(3))(12)(hmpz)(2)](n) (4) [aem = 4-(2-aminoethyl)morpholine; dmeen = N,N-dimethyl-N'-ethylethylenediamine; N,N'-dmen = N,N'-dimethylethylenediamine and hmpz = homopiperazine] have been synthesized by using 0.33 mol equiv of the chelating diamine ligands with Cu(NO(3))(2)·3H(2)O/CuCl(2)·2H(2)O and an excess of NaN(3). Single crystal X-ray structures show that the basic unit of these complexes, especially 1-3, contains very similar Cu(II)(6) building blocks. But the overall structures of these complexes vary widely in dimensionality. While 1 is three-dimensional (3D) in nature, 2 and 3 have a two-dimensional (2D) arrangement (with different connectivity) and 4 has a one-dimensional (1D) structure. Cryomagnetic susceptibility measurements over a wide range of temperature exhibit dominant ferromagnetic behavior in all the four complexes. The experimental susceptibility data have been analyzed by some theoretical model equations.