We predicted a new ternary hydride Li2SiH6 at high pressures. A systematic structure search in Li2SiH6 compound reveals novel stable phases with intriguing electronic and phonon properties. It is found that Li2SiH6 is dynamically stable from ambient pressure up to 400 GPa with three novel phases: P312, P3ˉ, and P6ˉ2m. The calculation of electron-phonon coupling combined with Bardeen-Cooper-Schrieffer's argument indicates that this compound may be a candidate for high Tc superconductors under high pressures. In particular, the maximum Tc of P6ˉ2m-Li2SiH6 at 400 GPa reaches 56 K. These findings may pave the way for obtaining room temperature superconductors in dense hydrogen-rich compounds.
@article{arxiv.2209.05014,
title = {Phase Transitions and Superconductivity in Ternary Hydride Li$_2$SiH$_6$ at High Pressures},
author = {Sixuan Wu and Bin Li and Zhi Chen and Yu Hou and Yan Bai and Xiaofeng Hao and Yeqian Yang and Shengli Liu and Jie Cheng and Zhixiang Shi},
journal= {arXiv preprint arXiv:2209.05014},
year = {2022}
}