AN EPR AND ELECTRONIC SPECTRAL STUDY OF SOME INTERACTIONS OF BIS(DIETHYL-DISELENOCARBAMATO)COPPER(II) COMPLEXES IN SOLUTION

Interactions of the complex bis(diethyl-diselenocarbamato)copper(II), (Cu(dsc)(2)) with Some copper(II) salts in solution have been studied by EPR and electronic spectroscopy. The complex interacts with copper salts (CuX2, X = Cl, Br, NO3) to produce EPR silent dimers of the type [(dsc)CuX2Cu(dsc)] which are formed in equilibrium with mixed-ligand Cu(dsc)X complexes. The same dimers are found to be formed in the cour se of the exchange reaction between the zinc diselenocarbamate and cop per chloride. The electronic spectrum of the bis-chelate has a charact eristic absorption band at 20,200 cm(-1) (epsilon = 11,800 m(-1) dm(3) cm(-1)) whereas the dimers are characterized by a band at 22,600 cm(- 1) (epsilon = 23,800 m(-1) dm(3) cm(-1)). This property of complex cou ld be used in analytical practice for increasing sensitivity of photom etric estimations. (C) 1998 Elsevier Science Ltd. All rights reserved.