Theoretical study on the Y-Ba-H hydrides at high pressure
作者：HaifengLiu, Rong Cheng, Kaiping Yang, Bingyu Li, Lingyan Chen, WencaiLu
關鍵字：high pressure, Y-Ba-H hydrides
論文來源：期刊
具體來源：Physics Letters A
發(fā)表時間：2020年
It has been a hot issue to search for hydrides at high pressure with high superconducting transition temperature (Tc). In this work, we studied YBaHn(n =2～12) at 50 -200 GPa and found that most of YBaH2?12are thermodynamically stable with respect to the elementary YBa and H systems at this pressure range. The most stable phases of YBaH4, YBaH5and YBaH8from genetic algorithm (GA) search have C2/m, P3m1 and P4/mmmsymmetries at 50 GPa, and P6/mmm, R3mand P4/mmmat 150 GPa, respectively. The P4/mmm-YBaH8was suggested to be formed by BaH2+YH6→YBaH8. In addition, the electric properties, phonon spectra and the superconductivity of the YBaH8and BaH2were calculated and discussed. The Tcof P4/mmm-YBaH8was predicted to be 49.6 K at 50 GPa and 89.4 K at 150 GPa.