Nature of the transformation in liquid iodine at 4 GPa
Nature of the transformation in liquid iodine at 4 GPa
复制标题
4 GPa 下液态碘的转化性质
DOI：
10.1103/physrevb.96.024105
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发表时间：
2017
影响因子：
3.7
通讯作者：
Kimura Masao
中科院分区：
文献类型：
--
作者：
Wakabayashi Daisuke;Funamori Nobumasa;Kikegawa Takumi;Watanabe Kazuki;Kohara Shinji;Nitani Hiroaki;Niwa Yasuhiro;Takeichi Yasuo;Abe Hitoshi;Kimura Masao
为了弄清液态碘在4 Gpa左右发生转变的性质，我们进行了高达9 Gpa的X射线吸收精细结构(XAFS)和X射线衍射(XRD)测量。在XAFS谱中，可归因于分子键的振荡持续到9 Gpa，但在4-5 Gpa以上表现出显著的衰减。类似地，在从X射线衍射谱得到的配对分布函数中，分配给分子键的峰持续到9 Gpa，但在4-5 Gpa以上显示出显著的展宽。当体积显著收缩(大于)时，分子键在1~9 Gpa之间随着压力的增加而膨胀。详细的分析，借助于反向蒙特卡罗模拟技术，阐明了这种转变的特征可能是相邻分子之间重新键合的开始(或几率的急剧增加)和电子态的变化(可能是金属化)，而不是分子解离。
To clarify the nature of the transformation in liquid iodine, which is reported to occur at around 4 GPa, we have conducted x-ray absorption fine structure (XAFS) and x-ray diffraction (XRD) measurements up to 9 GPa. In the XAFS spectra, the oscillation attributable to the molecular bond persisted to 9 GPa but showed a significant decay above 4–5 GPa. Similarly, in the pair-distribution function obtained from XRD profiles, the peak assigned to the molecular bond persisted to 9 GPa but showed a significant broadening above 4–5 GPa. While the volume contracts significantly (more than), the molecular bond expands by aboutwith increasing pressure between 1 and 9 GPa. Detailed analyses, with the aid of Reverse Monte Carlo modeling techniques, clarify that the transformation may be characterized by the onset (or drastic increase in the probability) of rebonding among adjacent molecules and the change in electronic state (possibly metallization) without molecular dissociation.