Study of excitation energy migration and transfer in 3,3′-dimethyloxacarbocyanine iodide (DMOCI) and o-(6-diethylamino-3-diethylimino-3H-xanthen-9-yl) benzoic acid (RB) in thin films of polyvinyl alcohol

Abstract

Abstract Excitation energy migration and transfer study in a new dye pair 3,3 ′ -dimethyloxacarbocyanine iodide (DMOCI) (donor) to o -(6-diethylamino-3-diethylimino-3H-xanthen-9-yl) benzoic acid (RB) (acceptor) has been carried out in thin films of polyvinyl alcohol (PVA) by steady state and ps time-resolved spectroscopy. It is found that at low donor and high acceptor concentration the Forster type (non-radiative) energy transfer takes place directly from donor to acceptor, whereas in case of low acceptor concentrations the excitation energy migration through donor–donor interaction dominates over the direct donor–acceptor transfer. The observed behaviour has been explained on the basis of theoretical models of Loring, Anderson and Fayer (LAF) and Huber.