Mott-Jahn-Teller insulator

Fabrizio and Tosatti introduced the idea of the Mott-Jahn-Teller insulator and performed a model calculation for an E system. Dunn [11,17] extended this model to the p" l h system for fullerenes and determined the properties of various cooperative JT distorted phases. 

From the data on divalent and tetravalent salts, a consistent picture emerges which is in perfect agreement with the Mott-Jahn-Teller insulator model of Fabrizio and Tosatti [16]. The Jahn-Teller distortion, even if dynamic, can be unambigously detected from vibrational and low-energy electronic spectra and proves that the molecular JT effect causes the nonmagnetic insulating behavior in these materials. Systems with smaller cations are on the metallic side of the UAV diagram it would be of interest to study these systems by vibrational spectroscopy as well. 

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