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arXiv · 2004.11320

Prediction of an Extended Ferroelectric Clathrate

Li Zhu·Timothy A. Strobel·R. E. Cohen
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Abstract

Using first-principles calculations, we predict a lightweight room-temperature ferroelectric carbon-boron framework in a host/guest clathrate structure. This ferroelectric clathrate, with composition ScB$_3$C$_3$, exhibits high polarization density and low mass density compared with widely used commercial ferroelectrics. Molecular dynamics simulations show spontaneous polarization with a moderate above-room-temperature T$_c$ of $\sim$370 K, which implies large susceptibility and possibly large electrocaloric and piezoelectric constants at room temperature. Our findings open the possibility for a new class of ferroelectric materials with potential across a broad range of applications.

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Li Zhu, Timothy A. Strobel, R. E. Cohen. 2020-04-23. Prediction of an Extended Ferroelectric Clathrate. https://doi.org/10.1103/physrevlett.125.127601

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