UV-vis, IR spectra and thermal studies of charge transfer complex formed between poly(amidoamine) dendrimers and iodine

The intermolecular charge-transfer (CT) complexes formed between two poly(amidoamine) dendrimers (PAMAM) from zero (D1) and second generation (D2) as donor and iodine as sigma-acceptor have been studied spectrophotometrically in the chloroform medium. The suggested structures of the solid iodine charge-transfer complexes investigated by several techniques using elemental analysis, mid infrared spectra, and thermal analysis (TGA and DTG) of the solid CT-complexes along with the photometric titration curves for the reactions. The results indicate the formation of two CT-complexes {[}(D1)]-I-2 and {[}(D2)]-2I(2) with acceptor:donor molar ratios of 1 : 1 and 1 : 2, respectively. The kinetic parameters (non-isothermal method) for their decomposition have been evaluated by graphical methods using the equations of Horowitz-Metzger (HM) and Coats-Redfern (CR). (c) 2006 Elsevier B. V. All rights reserved.