The electronic spectra of the bis(dithiocarbamate) chelates of Cu(II) and Zn(II)

Abstract

This work deals with the synthesis of dithiocarbamate chelates of Cu(II) and Zn(II) with ligands derived from dimethyl-, diethyl-, dipropyl-, dibutyl- and methylisopropylamine, piperidine and morpholine and the electronic spectra of these substances in the UV and visible regions. The absorption spectra of the cupric (and zinc(II)) chelates contain a single analytically important band around 270 (260) nm, assigned to the π-π* transition within the ligand, that is affected by the substituent on the nitrogen atom and the solvent polarity. Lengthening of the alkyl chain leads to increased intensity of the bands and a red shift of their λmax; increased solvent polarity leads to increased intensity of the bands and a blue shift.