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Berry-Phase and Symmetry of the Ground State in Dynamical Jahn-Teller Systems

Paolo De Los Rios·Nicola Manini
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Abstract

We show through selected examples, relevant to the physics of fullerene ions, that the presence of a Berry phase in dynamical Jahn-Teller systems does not guarantee the degeneracy of the ground state, contrary to what previously believed. Moreover, we introduce a new class of Jahn-Teller systems with no Berry phase, as a generalization of the basic icosahedral $H \otimes h$ case.

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Paolo De Los Rios, Nicola Manini. 1997-09-08. Berry-Phase and Symmetry of the Ground State in Dynamical Jahn-Teller Systems. https://arxiv.org/abs/cond-mat/9709094

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