Exploring the Coexistence Conditions and Intrinsic Relationships between Electrides, Superconductivity, Kagome Lattice, and Superionic Behaviors in Li–Ge Compounds
Xinwei Wang, Wenting Tang, Xiao Wei Sun, Zi‐Jiang Liu, Bohan Cao, Mengxin Yang, Yibo Sun, Tian Cui, Liang Li, Fubo Tian
Abstract
A systematic prediction of crystal structures of the Li x Ge ( x = 1–8) system is performed using a combination of structure prediction and ab initio calculations coupled with deep learning methods. The structural features are discussed in terms of high-coordination and layered structures. The Dirac cones, flat bands, and van Hove singularities in the Kagome lattice formed by interstitial quasi-atoms, Li, and Ge atoms are explored. The superconductivity of the Li 5 Ge- P 6/ mmm is also predicted at 0–100 GPa. The deep learning simulations revealed that the Ge atoms in the Li 5 Ge- P 6/ mmm remained solid at 0 GPa and 400 K, while the Li atoms melted and entered a superionic state. Finally, the P - T phase diagram of Li 5 Ge- P 6/ mmm is presented at pressures from 0 to 100 GPa. Our results indicate that the layered and high coordination structures in Li-rich compounds provide an excellent platform for understanding the abundant physical properties and their coexistence.