Pressure-induced structural transitions in europium to 92 GPa

被引：33

作者：

Bi, W. ^{[1
]}

Meng, Y. ^{[2
]}

Kumar, R. S. ^{[3
,4
]}

Cornelius, A. L. ^{[3
,4
]}

Tipton, W. W. ^{[5
]}

Hennig, R. G. ^{[5
]}

Zhang, Y. ^{[3
,4
]}

Chen, C. ^{[3
,4
]}

Schilling, J. S. ^{[1
]}

机构：

[1] Washington Univ, Dept Phys, St Louis, MO 63130 USA

[2] Carnegie Inst Sci, HPCAT, Argonne, IL 60439 USA

[3] Univ Nevada, Dept Phys, Las Vegas, NV 89154 USA

[4] Univ Nevada, High Pressure Sci & Engn Ctr, Las Vegas, NV 89154 USA

[5] Cornell Univ, Dept Mat Sci & Engn, Ithaca, NY 14853 USA

来源：

PHYSICAL REVIEW B | 2011年 / 83卷 / 10期

基金：

美国国家科学基金会;

关键词：

RARE-EARTH-METALS; INTERMEDIATE VALENCE; EU; PHASE; SUPERCONDUCTIVITY; YTTERBIUM; ELEMENTS; CRYSTAL; 4F;

D O I：

10.1103/PhysRevB.83.104106

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Synchrotron x-ray diffraction experiments have been carried out on europium metal at ambient temperature to pressures as high as 92 GPa (0.92 Mbar). Following the well-known bcc-to-hcp transition at 12 GPa, a mixed-phase region is observed from 18 to 66 GPa until finally a single orthorhombic (Pnma) phase persists from 66 to 92 GPa. These results are compared to predictions from density functional theory calculations. Under pressure the relatively large molar volume V-mol of divalent Eu is rapidly diminished, equaling or falling below V-mol(P) for neighboring trivalent lanthanides above 15 GPa. The present results suggest that above 15 GPa Eu is neither divalent nor fully trivalent to pressures as high as 92 GPa.

引用

页数：8

共 36 条

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