Optical absorption spectra of A6C60: Reduction of effective Coulomb interactions
نویسنده
چکیده
Optical absorption spectra of C 60 are theoretically investigated in order to analyze the optical properties of alkali metal doped fullerites A6C60. We use a tight binding model with long ranged Coulomb interactions and bond disorder. Optical spectra are obtained by the Hartree-Fock approximation and the CI method. The Coulomb interaction parameters which are relevant to the optical spectra of A6C60 are almost the half of those of the neutral C60. The reduction of the effective Coulomb interactions is concluded for the heavily doped case of C60.
منابع مشابه
Optical-absorption spectra in fullerenes C60 and C70: Effects of Coulomb interactions, lattice fluctuations, and anisotropy.
(Received) ABSTRACT Effects of Coulomb interactions and lattice fluctuations in the optical absorption spectra of C 60 and C 70 are theoretically investigated by using a tight binding model with long-range Coulomb interaction and bond disorder. Anisotropy effects in C 70 are also considered. Optical spectra are calculated by using the Hartree-Fock approximation followed by the configuration int...
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