Neutron Scattering Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA.
Sci Rep. 2023 Mar 23;13(1):4741. doi: 10.1038/s41598-023-31295-3.
Over the last 60 years, the diamond anvil cell (DAC) has emerged as the tool of choice in high pressure science because materials can be studied at megabar pressures using X-ray and spectroscopic probes. In contrast, the pressure range for neutron diffraction has been limited due to low neutron flux even at the strongest sources and the resulting large sample sizes. Here, we introduce a neutron DAC that enables break-out of the previously limited pressure range. Key elements are ball-bearing guides for improved mechanical stability, gem-quality synthetic diamonds with novel anvil support and improved in-seat collimation. We demonstrate a pressure record of 1.15 Mbar and crystallographic analysis at 1 Mbar on the example of nickel. Additionally, insights into the phase behavior of graphite to 0.5 Mbar are described. These technical and analytical developments will further allow structural studies on low-Z materials that are difficult to characterize by X-rays.
在过去的 60 年中，金刚石对顶砧（DAC）因其可利用 X 射线和光谱探针在兆巴压力下研究材料而成为高压科学的首选工具。相比之下，由于中子通量低，即使在最强的源处，中子衍射的压力范围也受到限制，这导致了较大的样品尺寸。在这里，我们引入了一种可突破先前压力范围限制的中子 DAC。关键元件是滚珠轴承导向装置，用于提高机械稳定性、具有新型砧座支撑和改进的在位准直的宝石级合成钻石。我们以镍为例，展示了 1.15 Mbar 的压力记录和 1 Mbar 下的晶体学分析。此外，还描述了石墨在 0.5 Mbar 下的相行为。这些技术和分析上的发展将进一步允许对低 Z 材料进行结构研究，这些材料很难用 X 射线进行表征。
