High-temperature superconducting electride in compressed lithium-silver compounds: Multicentered chemical bonding driven by interstitial spz-hybridization

作者：Yao Sun, Jianbo Wu, Lihua Yang, Shoutao Zhang, Xin Zhong, Hanyu Liu · 发表于：Computational Materials Today · 年份：2025 · DOI：10.1016/j.commt.2025.100035 · 被引用次数：8 · 研究领域：Ammonia Synthesis and Nitrogen Reduction、Hydrogen Storage and Materials、Inorganic Chemistry and Materials

The exploration of high-temperature superconductivity in lithium-rich compounds under extreme compression has revealed significant potential in quantum materials design. Here, we employ advanced crystal structure prediction and first-principles calculations to systematically investigate the Li-Ag system across 100-300 GPa, identifying two thermodynamically stable structures: Cmcm Li 7 Ag (104-190 GPa) and its pressure-induced Pnnm analog (>190 GPa). Both structures exhibit exceptional superconducting transition temperatures ( T c = 40 K at 180-200 GPa), rivaling the benchmark superconductor MgB 2 (39 K). Structural analysis reveals prominent ellipsoidal charge concentration regions localized within Li 8 hexahedral interstitial sites, aligned with the polyhedral framework. Wannier function analysis demonstrates that the interstitial charge localization originates from multicentered Li-dominated sp z -hybridization, where directional orbital interactions mediate electron density accumulation rather than conventional non-nuclear quasi atoms model. The interaction of Li p -electrons and Ag p -electrons with the Li atomic framework leads to a significant enhancement of the T c value. T hese results underscore the potential for high- T c supercondu c tivity in lithium-rich compounds, offering key insights into the exploration of superconducting materials.