First-principles search of hot superconductivity in La-X-H ternary hydrides  

作　　者：Simone Di Cataldo Wolfgang von der Linden Lilia Boeri 

机构地区：[1]Institute of Theoretical and Computational Physics,Graz University of Technology,NAWI Graz,8010,Graz,Austria [2]Dipartimento di Fisica,Sapienza Universitàdi Roma,00185,Roma,Italy [3]Centro Ricerche Enrico Fermi,Via Panisperna,89a,00184,Roma,Italy

出　　处：《npj Computational Materials》2022年第1期1-8,共8页计算材料学（英文）

基　　金：the dCluster of the Graz University of Technology and the VSC3 of the Vienna University of Technology,and support through the FWF,Austrian Science Fund,Project P30269-N36(Superhydra);L.B.acknowledges funding through Progetto Ateneo Sapienza 2017-18-19 and computational Resources from CINECA,proj.Hi-TSEPH.S.D.C.acknowledges computational Resources from CINECA,proj.IsC90-HTS-TECH_C,and the dCluster of the Graz University of Technology.

摘　　要：Motivated by the recent claim of hot superconductivity with critical temperatures up to 550 K in La + x hydrides,we investigate the high-pressure phase diagram of compounds that may have formed in the experiment,using first-principles calculations for evolutionary crystal structure prediction and superconductivity.Starting from the hypothesis that the observed T_(c) may be realized by successive heating upon a pre-formed LaH_(10) phase,we examine plausible ternaries of lanthanum,hydrogen and other elements present in the diamond anvil cell: boron,nitrogen,carbon,platinum,gallium,gold.We find that only boron and,to a lesser extent,gallium form metastable superhydride-like structures that can host high-T_(c) superconductivity,but the predicted T_(c)’s are incompatible with the experimental reports.Our results indicate that,while the claims of hot superconductivity should be reconsidered,it is very likely that unknown H-rich ternary or multinary phases containing lanthanum,hydrogen,and possibly boron or gallium may have formed under the reported experimental conditions,and that these may exhibit superconducting properties comparable,or even superior,to those of currently known hydrides.

关 键 词：hydrides BORON SUPERCONDUCTIVITY 

分 类 号：O613.2[理学—无机化学]