氢的高压奇异结构与金属化  

On the Novel Structure and Metallization of Hydrogen under High Pressure

作　　者：耿华运[1] 孙毅 

机构地区：[1]中国工程物理研究院流体物理研究所冲击波物理与爆轰物理重点实验室,四川绵阳621999

出　　处：《高压物理学报》2018年第2期1-12,共12页Chinese Journal of High Pressure Physics

基　　金：国家自然科学基金(11672274;11274281);国家自然科学基金委员会-中国工程物理研究院"NSAF"联合基金(U1730248);中国工程物理研究院发展基金(2012A0101001;2015B0101005);冲击波物理与爆轰物理重点实验室基金(6142A03010101)

摘　　要：在极端压缩状态下,氢呈现出丰富的物理及化学变化,其结构与相图揭示了凝聚态物质高压行为的典型特征,在天体物理和新材料研究中有重要应用。本文简要回顾了金属氢概念的提出,以及直至最近几年的研究进展,分析总结了高密度氢研究中的一些核心问题和发展态势。利用密度泛函理论计算和状态方程模型分析,综合探讨了氢在高压下复杂的原子结构、分子氢离解区域附近的复杂行为、金属氢的亚稳定性和可回收性,以及"DAC+冲击"加载方法在金属氢研究中的优势与不足等问题。结果表明:通过快速或缓慢的压力释放回收金属氢的高压相到常压是几乎不可能的;高压下氢的复杂行为给实验和理论研究带来了巨大挑战,特别是离解区域附近理论与理论、实验与实验、以及理论与实验之间的结果都存在巨大差异,暗示当前通用的实验测试方法和常用的多电子理论计算方法还存在很大的改进空间。Hydrogen under extremely compressed conditions exhibits extraordinary richness in physics and chemistry.Its structural transitions and phase diagram are fundamental for understanding the high pressure behavior of condensed matters,and also for important applications in astrophysics and material science.In this paper,we reviewed the research progress on metallic hydrogen since it was proposed until to very recent years.Several key issues and possible future progress about dense hydrogen are analyzed and summarized.With density functional theory calculations and a model analysis using an equation of states,we explored and demonstrated：（1）the complex and novel atomic structures of dense hydrogen;（2）the novel behaviors of hydrogen molecules near the dissociation region;（3）the stability of metallic hydrogen under pressure and the possibility of recovery to zero pressure;（4）the advantages and disadvantages of the＂DAC＋shock＂experimental method to achieve metallic hydrogen.Our results showed that it is impossible to quench the high pressure phases of metallic hydrogen to ambient conditions.The complex behaviors of dense hydrogen present as a great challenge for both experimental and theoretical studies,especially near the dissociation of hydrogen molecules,where sharp discrepancies were unveiled,implying that much effort is still required to improve the state-ofthe-art experimental and many-body theoretical methods.

关 键 词：金属氢 结构与相图 量子固体和液体 高压 

分 类 号：O521.2[理学—高压高温物理]