The Energy Spectrum and Optical Absorption Spectrum of Endohedral Fullerenes Lu3N@C80 and Y3N@С80 within the Hubbard Model

The anticommutator Green’s functions and energy spectra of fullerene С 80 and endohedral fullerenes Lu 3 N@C 80 and Y 3 N@С 80 with symmetry group I h are obtained analytically within the Hubbard model in the static fluctuation approximation. Their energy states are classified and allowed transitions in the energy spectra of the С 80 , Lu 3 N@C 80 and Y 3 N@С 80 molecules are determined using group-theory methods. The experimentally observed optical absorption bands of endohedral fullerenes Lu 3 N@C 80 and Y 3 N@С 80 are interpreted based on the energy spectra.