Magnetic Properties of Polymorphic Cu(C3H3N2)2 Complexes

Abstract

The magnetization (M ) and the electron paramagnetic resonance (EPR) spectra of six polymorphs of the Cu(C3H3N2)2 complexes are reported along with the x-ray powder diffraction data. The magnetic susceptibility χ(T ) = M/µ 0 H shows Curie-Weiss behavior above 150 K with values of effective moments corresponding to localized Cu(II) spins. The complexes exhibit a variety of magnetic behavior, ranging from the ferromagnetic (blue 1 modification), through the antiferromagnetic order (blue 2, olive and green) to the paramagnetic state (pink and green amorphous modifications). For the latter systems, the experimental data may be interpreted in terms of one-dimensional antiferromagnetic Heisenberg chain models. We suggest that the magnetism of the Cu(C3H3N2)2 complexes depends not only on the Cu(II) ions involved, but also on the spatial arrangement of ligand in respect to the central ions. 75.50.Xx; 82.35.Lr PACS

Dielectric properties of Co(CO3)(H2O)2(C3H4N2)2 and [Co(C3H3N2)2]n

“…When we deal with the Cu(Im) 2 and Zn(Im) 2 complexes, we see that the paramagnetic properties of Cu 2+ (ref. 42) correlate with lower 3 0 -value of 2.5-3.2 in Cu(Im) 2 (ref. 43) compared to that of Co(Im) 2 , while the diamagnetic properties due to zero magnetic moment of Zn 2+ , correspond to extremely low 3 0 -value of only 2.3 in Zn(Im) 2 .…”