Wang Zifan, Yang Wenge, Kim Duck Young
Center for High Pressure Science & Technology Advanced Research (HPSTAR), Shanghai, 201203, P.R. China.
Shanghai Key Laboratory of Material Frontiers Research in Extreme Environments (MFree), Shanghai Advanced Research in Physical Sciences (SHARPS), Pudong, Shanghai, 201203, P. R. China.
Adv Sci (Weinh). 2025 Mar;12(9):e2415387. doi: 10.1002/advs.202415387. Epub 2025 Jan 13.
Under extreme conditions, condensed matters are subject to undergo a phase transition and there have been many attempts to find another form of hydroxide stabilized over HO. Here, using Density Functional Theory (DFT)-based crystal structure prediction including zero-point energy, it is that proton superoxide (HO), the lightest superoxide, can be stabilized energetically at high pressure and temperature conditions. HO is metallic at high pressure, which originates from the 𝜋 orbitals overlap between adjacent superoxide anions (O ). By lowering pressure, it undergoes a metal-to-insulator transition similar to LiO. Ab initio molecular dynamics (AIMD) calculations reveal that HO becomes superionic with high electrical conductivity. The possibility of creating hydrogen-mixed superoxide at lower pressure using a (Li,H)O hypothetical structure is also proposed. This discovery bridges gaps in superoxide and superionicity, guiding the design of various H-O compounds under high pressure.
在极端条件下，凝聚态物质会发生相变，人们已经进行了许多尝试来寻找另一种比超氧化氢（HO）更稳定的氢氧化物形式。在此，通过基于密度泛函理论（DFT）的晶体结构预测，包括零点能，发现最轻的超氧化物——质子超氧化物（HO）在高压和高温条件下在能量上可以稳定存在。HO在高压下是金属性的，这源于相邻超氧阴离子（O ）之间的π轨道重叠。通过降低压力，它会经历类似于LiO的金属-绝缘体转变。从头算分子动力学（AIMD）计算表明，HO会变成具有高电导率的超离子态。还提出了使用（Li，H）O假设结构在较低压力下制备氢混合超氧化物的可能性。这一发现填补了超氧化物和超离子性之间的空白，为高压下各种H-O化合物的设计提供了指导。
