Eosin Y–macromolecule complexes. Part 1.—Application of exciton theory to the study of the arrangement of eosin Y molecules in polycation-induced eosin Y dimers
Abstract
Evidence is presented for the formation of eosin Y dimers as the highest aggregates of complexes between eosin Y and poly-L-lysine, poly(p-xylyl viologen) or cetyl pyridinium. The absorption spectra of these complexes have been obtained free from contamination by eosin Y monomer spectrum and have been fitted with Gaussian band models using a non-linear least-squares fitting computer program. Using such models, simple excition theory had been employed to calculate parameters such as the orientations and molecular separations of the components of the eosin Y dimer. Where appropriate these parameters have been compared with the dimensions of the repeating unit and the possible conformations of the polymer.