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Ferroelectricity in (K@C$_{60}$)$_n$

Dennis P. Clougherty
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Abstract

A theoretical analysis of the ground state of long-chain (K@C$_{60}$)$_n$ is presented. Within mean field theory, a ferroelectric ground state is found to be stable because of the pseudo-Jahn-Teller mixing of the b$_{1u}$ and the b$_{2g}$ band with a zone-center optical phonon involving the displacement of the endohedral K^+ ions. A phase diagram for this model is derived in the narrow bandwidth regime.

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Dennis P. Clougherty. 2002-12-20. Ferroelectricity in (K@C$_{60}$)$_n$. https://doi.org/10.1063/1.1324462

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