Two new neutral copper-azido polymers [Cu3(N3) 6(tmen)2]n (1) and [Cu6(N 3)12(deen)2]n (2) [tmen = N,N,N,N -tetramethylethylenediamine and deen = N,N-diethylethylenediamine] have been synthesized by using lower molar equivalents of the chelating diamine ligands with Cu(NO3)2 {\textperiodcentered} 3H2O and an excess of NaN3. The single crystal X-ray structure shows that in the basic unit of the 1D complex 1, the three Cu" ions are linked by double end-on azido bridges with CU-NEO-CU angles on both sides of the magnetic exchange critical angle of 108°. Complex 2 is a 3D framework of a basic Cu6 cluster. Cryomagnetic susceptibility measurements over a wide range of temperature exhibit dominant ferromagnetic behavior in both the complexes. Density functional theory calculations (B3LYP functional) have been performed on the trinuclear unit to provide a qualitative theoretical interpretation of the overall ferromagnetic behavior shown by the complex 1. {\textcopyright}2009 American Chemical Society.