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arXiv · 1211.6948

First-Principles Determination of the Structure of Magnesium Borohydride

Xiang-Feng Zhou·Artem R. Oganov·Guang-Rui Qian·Qiang Zhu
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Abstract

The energy landscape of Mg(BH4)2 under pressure is explored by ab initio evolutionary calculations. Two new tetragonal structures, with space groups P-4 and I41/acd are predicted to be lower in enthalpy, by 15.4 kJ/mol and 21.2 kJ/mol, respectively, than the earlier proposed P42nm phase. We have simulated X-ray diffraction (XRD) spectra, lattice dynamics, and equations of state (EOS) of these phases. The density, volume contraction, bulk modulus, and the simulated XRD patterns of I41/acd and P-4 structures are in excellent agreement with the experimental results.

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Xiang-Feng Zhou, Artem R. Oganov, Guang-Rui Qian, Qiang Zhu. 2012-12-10. First-Principles Determination of the Structure of Magnesium Borohydride. https://doi.org/10.1103/physrevlett.109.245503

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