Authors:B. C. Stojceva Radovanovic and P. I. Premovic
The urea complex of copper was synthesized and its structure was established by Fourier transform infrared (FTIR), electron spin resonance (ESR) and atomic absorption spectroscopy and elemental analysis to be Cu(urea)4Cl2. The thermal behaviour of this complex has been studied by thermogravimetry and differential thermal analysis and FTIR and ESR. Thermal analysis shows that the decomposition of the complex occurs in four stages of weight loss of different intermediates followed by three endothermal effects. The complex is thermally stable up to 428 K. The ESR and FTIR behaviour of the Cu(II)-urea complex during thermolysis was studied between 428 and 633 K. The experimental results suggest that in this temperature range the complex decomposition occurred forming thermodynamically stable regions of Cu(II) which are ferromagnetically coupled.