Spectroscopic and thermal studies of perylene charge-transfer complexes

Charge-transfer (CT) complexes formed between perylene (Pery) as donor with iodine (I-2), piciric acid (PA) and chloranilic acid (CLA) as acceptors were studied spectrophotometrically. The synthesis and characterization of perylene CT complexes of iodine, {[}(Pery)(2)]I+.I-3(-), picric acid, {[}(Pery)(PA)] and chloranilic acid, {[}(Pery)(CLA)] were described. These complexes were readily prepared by the reaction of Pery with I-2, PA and CLA using CHCl3 as a solvent. The IR, UV-Vis and (HNMR)-H-1 spectral techniques, as well as elemental analysis (carbon,hydrogen and nitrogen contents) and thermal analysis were used to characterize the three perylene charge-transfer complexes. Benesi-Hildebrand method and its modification were applied to the determination of association constant (K) and molar absorption coefficient (epsilon).