Metallization of magnesium polyhydrides under pressure

被引：119

作者：

Lonie, David C. ^{[1
]}

Hooper, James ^{[1
]}

Altintas, Bahadir ^{[1
,2
]}

Zurek, Eva ^{[1
]}

机构：

[1] SUNY Buffalo, Dept Chem, Buffalo, NY 14260 USA

[2] Abant Izzet Baysal Univ, Dept Comp Educ & Instruct Technol, TR-14280 Golkoy, Bolu, Turkey

来源：

PHYSICAL REVIEW B | 2013年 / 87卷 / 05期

基金：

美国国家科学基金会;

关键词：

AB-INITIO; CRYSTAL-STRUCTURE; HYDRIDE; DYNAMICS; PHASE; BULK; MGH2;

D O I：

10.1103/PhysRevB.87.054107

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Evolutionary structure searches are used to predict stable phases with unique stoichiometries in the hydrogen-rich region of the magnesium/hydrogen phase diagram under pressure. MgH4, MgH12, and MgH16 are found to be thermodynamically stable with respect to decomposition into MgH2 and H-2 near 100 GPa, and all lie on the convex hull by 200 GPa. MgH4 contains two H- anions and one H-2 molecule per Mg2+ cation, whereas the hydrogenic sublattices of MgH12 and MgH16 are composed solely of Hd(2)(delta-) molecules. The high-hydrogen content stoichiometries have a large density of states at the Fermi level, and the T-c of MgH12 at 140 GPa is calculated to be nearly three times greater than that of the classic hydride, MgH2, at 180 GPa. DOI: 10.1103/PhysRevB.87.054107

引用

页数：8

共 59 条

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