Linear optical properties of one-dimensional Frenkel exciton systems with intersite energy correlations

We analyze the effects of intersite energy correlations on the linear optic al properties of one-dimensional disordered Frenkel exciton systems. The ab sorption linewidth and the factor of radiative rate enhancement are studied as a function of the correlation length of the disorder. Thr absorption li ne width monotonously approaches the seeding degree of disorder on increasi ng the correlation length. On the contrary, the factor of radiative rate en hancement shows a nonmonotonous trend, indicating a complicated scenario of the exciton localization in correlated systems. The concept of coherently bound molecules is exploited to explain the numerical results, showing good agreement with theory. Some recent experiments are discussed in the light of the present theory. [S0163-1829(99)07343-9].