The crystal structure of α-MgD2 under high pressure by neutron powder diffraction

被引：14

作者：

Kohlmann, Holger ^{[1
]}

Zhao, Yusheng ^{[2
]}

Nicol, Malcolm F. ^{[3
]}

McClure, Jason ^{[3
]}

机构：

[1] Univ Saarland, D-66123 Saarbrucken, Germany

[2] Los Alamos Natl Lab, LANSCE Div, Los Alamos, NM 87545 USA

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

来源：

ZEITSCHRIFT FUR KRISTALLOGRAPHIE | 2008年 / 223卷 / 10期

关键词：

Neutron powder diffraction; High pressure; Metal hydrides; Magnesium deuteride; Rietveld refinement;

D O I：

10.1524/zkri.2008.1126

中图分类号：

O7 [晶体学];

学科分类号：

0702 ; 070205 ; 0703 ; 080501 ;

摘要：

The crystal structure of rutile-type magnesium deuteride, alpha-MgD(2), has been studied by in situ neutron powder diffraction at room temperature and pressures up to 9.3 GPa. The bulk modulus B(0) = 49(2) GPa is about half, the linear compressibilities (0.0063/GPa along a and 0.0041/GPa along c) are about twice and the variation of the free positional parameter x about six times the values for the isostructural magnesium fluoride, indicating the strong polarizability of the deuteride anion. Under pressure the MgD(6) octahedra are more compressed (four Mg-D distances at 199(1), two at 173(1) pm) than at ambient pressure (195.1(1), 194.8(2) pm) and the structural arrangement becomes more CaCl(2) like, although no structural phase transition has been observed.

引用

页码：706 / 710

页数：5

共 41 条

[1] Equations of state [J].