A ten-fold coordinated high-pressure structure in hafnium dihydrogen with increasing superconducting transition temperature induced by enhancive pressure  

作　　者：王妍琪 张传钊 张金权 李松 巨濛 孙伟国 豆喜龙 金园园 Yan-Qi Wang;Chuan-Zhao Zhang;Jin-Quan Zhang;Song Li;Meng Ju;Wei-Guo Sun;Xi-Long Dou;Yuan-Yuan Jin(Department of Physics and Optoelectronic Engineering,Yangtze University,Jingzhou 434023,China;School of Physical Science and Technology,Southwest University,Chongqing 400715,China;College of Physics and Electronic Information,Luoyang Normal University,Luoyang 471022,China;Institute of Atomic and Molecular Physics,Sichuan University,Chengdu 610065,China)

机构地区：[1]Department of Physics and Optoelectronic Engineering,Yangtze University,Jingzhou 434023,China [2]School of Physical Science and Technology,Southwest University,Chongqing 400715,China [3]College of Physics and Electronic Information,Luoyang Normal University,Luoyang 471022,China [4]Institute of Atomic and Molecular Physics,Sichuan University,Chengdu 610065,China

出　　处：《Chinese Physics B》2023年第9期455-462,共8页中国物理B（英文版）

基　　金：the National Natural Science Foundation of China(Grant Nos.11804031 and 11904297);the Scientific Research Project of Education Department of Hubei Province,China(Grant No.Q20191301);the Fundamental Research Funds for the Central Universities(Grant No.SWUKT22049);the Chongqing Talent Plan for Young Top Notch Talents,China(Grant No.202005007)。

摘　　要：High pressure is an effective method to induce structural and electronic changes,creating novel high-pressure structures with excellent physical and chemical properties.Herein,we investigate the structural phase transition of hafnium dihydrogen(HfH2)in a pressure range of 0 GPa-500 GPa through the first-principles calculations and the crystal structure analysis by particle swarm optimization(CALYPSO)code.The high-pressure phase transition sequence of HfH2is I4/mmm→Cmma→P-3m1 and the two phase transition pressure points are 220.21 GPa and 359.18 GPa,respectively.A newly trigonal P-3m1 structure with 10-fold coordination first appears as an energy superior structure under high pressure.These three structures are all metallic with the internal ionic bonding of Hf and H atoms.Moreover,the superconducting transition temperature(Tc)values of Cmma at 300 GPa and P-3m1 at 500 GPa are 3.439 K and 19.737 K,respectively.Interestingly,the superconducting transition temperature of the P-3m1 structure presents an upward trend with the pressure rising,which can be attributed to the increase of electron-phonon coupling caused by the enhanced Hf-d electronic density of states at Fermi level under high pressure.

关 键 词：transition metal dihydrogen first principles phase transition superconducting transition temperature 

分 类 号：O469[理学—凝聚态物理]