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arXiv · 2010.01469

Ternary Hypervalent Silicon Hydrides via Lithium at High Pressure

Tianxiao Liang·Zihan Zhang·Xiaolei Feng·Haojun Jia·Chris J. Pickard·Simon A. T. Redfern·Defang Duan
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Abstract

Hydrogen is rarely observed as ligand in hypervalent species, however, we find that high-pressure hydrogenation may stabilise hypervalent hydrogen-rich materials. Focussing on ternary silicon hydrides via lithium doping, we find anions composed of hypervalent silicon with H ligands formed under high pressure. Our results reveal two new hypervalent anions: layered-SiH$_{5}^{-}$ and tricapped trigonal prismatic SiH$_{6}^{2-}$. These differ from octahedral SiH$_{6}^{2-}$ described in earlier studies. In addition, there are further hydrogen-rich structures Li$_{3}$SiH$_{10}$ and Li$_{2}$SiH$_{6+\delta}$ which may be stabilised at high pressure. Our work provides pointers to future investigations on hydrogen-rich materials.

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Tianxiao Liang, Zihan Zhang, Xiaolei Feng, Haojun Jia, Chris J. Pickard, Simon A. T. Redfern, Defang Duan. 2020-10-04. Ternary Hypervalent Silicon Hydrides via Lithium at High Pressure. https://doi.org/10.1103/physrevmaterials.4.113607

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