ABSORPTION SPECTRA SIMULATION OF PERSISTENCE-TYPE CYANINE DYE AGGREGATES IN LB FILMS

Abstract

Simulation of the absorption spectra of the 2D persistence-type molecular aggregates consisting of the combination of oxacyanine dye (S9) and thiacyanine dye (S11) is being considered. These aggregates are modeled by square matrix structure in the extended dipole approximation. The simulation takes into account the vector properties of the transitional dipole moment, its orientation, diagonal disorder and the composition of the aggregate. Good fit with the experiment is obtained for dipole tilt angle θ=40°, dipole moment μ=8.1 D and the disorder parameter of 450 cm -1 for various molar fractions of dyes.