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arXiv · 1210.1489

Low-energy structures of zinc borohydride Zn(BH$_4$)$_2$

Tran Doan Huan·Maximilian Amsler·Vu Ngoc Tuoc·Alexander Willand·Stefan Goedecker
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Abstract

We present a systematic study of the low-energy structures of zinc borohydride, a crystalline material proposed for the hydrogen storage purpose. In addition to the previously proposed structures, many new low-energy structures of zinc borohydride are found by utilizing the minima-hopping method. We identify a new dynamically stable structure which belongs to the $I4_122$ space group as the most stable phase of zinc borohydride at low temperatures. A low transition barrier between $I4_122$ and $P1$, the two lowest-lying phases of zinc borohydride is predicted, implying that a coexistence of low-lying phases of zinc borohydride is possible at ambient conditions. An analysis based on the simulated X-ray diffraction pattern reveals that the $I4_122$ structure exhibits the same major features as the experimentally synthesized zinc borohydride samples.

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Tran Doan Huan, Maximilian Amsler, Vu Ngoc Tuoc, Alexander Willand, Stefan Goedecker. 2012-12-10. Low-energy structures of zinc borohydride Zn(BH$_4$)$_2$. https://doi.org/10.1103/physrevb.86.224110

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