Structure refinement of sub-cubic-mm volume sample at high pressures by pulsed neutron powder diffraction: application to brucite in an opposed anvil cell
Structure refinement of sub-cubic-mm volume sample at high pressures by pulsed neutron powder diffraction: application to brucite in an opposed anvil cell
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DOI：
10.1080/08957959.2014.909931
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发表时间：
2014-04
影响因子：
2
通讯作者：
T. Okuchi;N. Tomioka;N. Purevjav;J. Abe;S. Harjo;W. Gong
中科院分区：
文献类型：
--
作者：
T. Okuchi;N. Tomioka;N. Purevjav;J. Abe;S. Harjo;W. Gong
在日本质子加速器研究中心复合型脉冲中子源上，利用对置的顶压室和中分辨率衍射仪，在2.8 Gpa的压力下，对0.9mm~3的重水镁石和加压介质混合物进行了中子粉末衍射测量。成功地获得了无杂散的衍射图，并对其进行了改进，以提供包括德拜-沃勒因子在内的所有结构参数。水镁石的羟基偶极向三个最接近的氧阴离子之一倾斜，证实在低至1.5 Gpa的压力下是相当大的。通过这一应用，为分析如此小的样品建立了新的技术可行性，这将有助于扩大高压下中子衍射的应用。
Neutron powder diffraction measurements of 0.9 mm3 of mixture of deuterated brucite and pressure medium were conducted at pressures to 2.8 GPa, using an opposed anvil cell and a medium-resolution diffractometer at Japan Proton Accelerator Research Complex pulsed neutron source. Spurious-free diffraction patterns were successfully obtained and refined to provide all structural parameters including Debye–Waller factors. Tilting of hydroxyl dipoles of brucite toward one of the three nearest-neighbor oxygen anions was confirmed to be substantial at pressure as low as 1.5 GPa. By this application, technical feasibility to analyze such a small sample has been newly established, which would be useful to extend the applications of neutron diffraction at high pressures.