The Linear Optical Polarizability Spectra of Five C 78 Isomers

Effects of anisotropy, symmetry, atom arrangement and Coulomb interaction on the linear optical polarizability spectra of five C 78 isomers are theoretically studied by using the extended Su–Schrieffer–Heeger model with and without Coulomb interaction. The main results are as follows. 1) The spectra become anisotropic with respect to the direction of the electric field of light. The property is common in the niorlel with and without Coulomb interaction. 2) The symmetry and atom arrangement have grcat effects on the peak positions, strengths, and number. 3) The Coulomb interaction tends to shift peaks to higher energies and enhances the oscillator strengths at higher energies.