Electronic Excitations and Stability of the Ground State of C60 Molecules

F. Bechstedt; M. Fiedler; L. J. Sham

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arXiv · cond-mat/9807144

Electronic Excitations and Stability of the Ground State of C60 Molecules

F. Bechstedt·M. Fiedler·L. J. Sham

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Abstract

A model study of the singlet excitons in the C60 molecule with emphasis on the Coulomb interaction between excited electron and hole leads to a physical understanding of the interaction effects on the absorption spectra and to a new identification of the forbidden excitons in the third-harmonic generation spectra. These conclusions may be tested experimentally on the model predictions related to the optical Kerr effect. The model shows that, with sufficiently strong interatomic than onsite interaction, a T_{2G} exciton could have very low energy or become unstable against the closed-shell ground state. Properties of these interesting cases beyond the C60 are briefly examined.

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F. Bechstedt, M. Fiedler, L. J. Sham. 1998-07-09. Electronic Excitations and Stability of the Ground State of C60 Molecules. https://arxiv.org/abs/cond-mat/9807144

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