Ternary hypervalent silicon hydrides via lithium at high pressure

• Main Authors: Liang, Tianxiao, Zhang, Zihan, Feng, Xiaolei, Jia, Haojun, Pickard, Chris J., Redfern, Simon Anthony Turner, Duan, Defang
• Other Authors: Asian School of the Environment
• Format: Article
• Language: English
• Published: 2021
• Subjects: Science::Physics; Charge; Density of States
• Online Access: https://hdl.handle.net/10356/146521
• Institution: Nanyang Technological University

Hydrogen is rarely observed as a ligand in hypervalent species, however, we find that high-pressure hydrogenation may stabilize hypervalent hydrogen-rich materials. Focusing 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 different hypervalent anions: layered SiH5− and tricapped triangular prismatic SiH62−. These differ from octahedral SiH62− described in earlier studies. In addition, there are further hydrogen-rich structures, Li3SiH10 and Li2SiH6+δ, which may be stabilized at high pressure. Our work provides pointers to future investigations on hydrogen-rich materials.