压力稳定的超导氢化钇
Pressure-stabilized superconductive yttrium hydrides.
作者信息
Li Yinwei, Hao Jian, Liu Hanyu, Tse John S, Wang Yanchao, Ma Yanming
机构信息
1] School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China [2] State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012, China [3] Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, S7N 5E2, Canada.
School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China.
出版信息
Sci Rep. 2015 May 5;5:9948. doi: 10.1038/srep09948.
The search for high-temperature superconductors has been focused on compounds containing a large fraction of hydrogen, such as SiH4(H2)2, CaH6 and KH6. Through a systematic investigation of yttrium hydrides at different hydrogen contents using an structure prediction method based on the particle swarm optimization algorithm, we have predicted two new yttrium hydrides (YH4 andYH6), which are stable above 110 GPa. Three types of hydrogen species with increased H contents were found, monatomic H in YH3, monatomic H+molecular "H2" in YH4 and hexagonal "H6" unit in YH6. Interestingly, H atoms in YH6 form sodalite-like cage sublattice with centered Y atom. Electron-phonon calculations revealed the superconductive potential of YH4 and YH6 with estimated transition temperatures (Tc) of 84-95 K and 251-264 K at 120 GPa, respectively. These values are higher than the predicted maximal Tc of 40 K in YH3.
对高温超导体的研究一直集中在含有大量氢的化合物上，如硅烷（H2）2、氢化钙和氢化钾。通过基于粒子群优化算法的结构预测方法，对不同氢含量的氢化钇进行系统研究，我们预测了两种新的氢化钇（YH4和YH6），它们在110吉帕以上是稳定的。发现了三种氢含量增加的氢物种，YH3中的单原子氢、YH4中的单原子氢+分子“H2”以及YH6中的六方“H6”单元。有趣的是，YH6中的氢原子与中心钇原子形成类似方钠石的笼状亚晶格。电子-声子计算表明，YH4和YH6具有超导潜力，在120吉帕时估计的转变温度（Tc）分别为84-95K和251-264K。这些值高于YH3中预测的最大Tc值40K。
Zotero 插件