EXCITONS IN 2 COUPLED CONJUGATED POLYMER-CHAINS

We have studied the exciton states in two coupled conjugated polymer c hains which are modelled individually by the Su-Schrieffer-Heeger Hami ltonian and coupled by an interchain electron-transfer term. Both the intra- and interchain long-range Coulomb interactions are taken into a ccount. The properties of the lowest symmetric and anti-symmetric exci ton states are extensively discussed for both the parallel and anti-pa rallel ordering between these two chains. It is found that, for these two kinds of ordering, the features of excitons are quite different. P ossible implications for the experiment of luminescent polymers are al so addressed.