摘要
The recent observation of high critical temperature T_(c) in lanthanum and Yttrium hydrides confirms the key role of hydrogen cage(H-cage)in determining high superconductivity.Here,we present a new class of metastable H_(12) clathrate structures based on the icosahedral cI 24-Na that can be stabilized by incorporation of metal elements.Analysis shows that the charge transfer from metal atoms to H atoms contributes to forming the H_(12) clathrate.Nine dynamically stable structures are identified to exhibit superconductivity,and a maximum T_(c) of 28K is found in voids-doped Mo_(6)H_(24).Calculations reveal that the low T_(c) is attributed to the weak interaction between H atoms in each cage due to the long H–H distance.The current results provide a possible route to design H-cage containing superconductors.
基金
Supported by the National Natural Science Foundation of China(Grant Nos.12074154,11722433,11804128,11804129,and 11904142)
the Qing Lan Project of Jiangsu Province.
