Fe b 19 97 Non magnetic molecular Jahn - Teller Mott insulators
نویسنده
چکیده
Narrow-band conductors may turn insulating and magnetic as a consequence of strong electron-electron correlation. In molecular conductors, the concomitance of a strong Jahn-Teller coupling may give rise to the alternative possibility of a non-magnetic insulator, with or without a static cooperative Jahn-Teller distortion. In the latter case the insulator has Mott-like properties, with an interesting interplay between electron-electron repulsion and the Jahn-Teller effect, which is dynamical. We study this kind of non-magnetic insulator in a very simple E ⊗ e Jahn-Teller model and we discuss its general properties in a more general context, also in connection with the insulating state of K4C60 and Rb4C60. Typeset using REVTEX 1
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