Optical and magneto-optical properties of the monoclinic phase of the C70 crystal

Using the Hartree-Fock (HF) single-excitation configuration interaction (CI) model in conjunction with the local field method, the dielectric tensor, birefringence coefficient, circular dichroism, refractive index and effects of spatial dispersion on the dispersion relation for transverse normal polariton waves of the monoclinic phase of the C-70 crystal are calculated. Our results indicate that the anisotropy of the C-70 molecule remains in C-70 solids. Also, our results on the effect of spatial dispersion, compared with the non-dispersive case, indicate that the coupling of the transverse electromagnetic field with the first and second excitonic states is very weak.