Laser-Radiation-Induced Optical Anisotropy of Rhodamine Dye Solutions

We have made spectral studies of induced optical anisotropy (its quantitative measure is the difference of refractive indices of the ordinary and extraordinary beams n = n _o – n _e) of Rhodamine 6G and 4C solutions in glycerol upon excitation in the UV region of the absorption spectrum. The observed spectral dependences of n of the above dye solutions excited in the UV (short-wavelength) and visible (long-wavelength) regions of the absorption spectrum are explained from the point of view of the molecular model. The proposed methods for investigating induced optical anisotropy of solutions of organic compounds make it possible to reliably determine the relative orientation of molecular electronic oscillators in the molecule skeleton and, consequently, the mutual orientation of the dipole moments of transitions.