冰的轻微排序状态IV 通过"在现场"中子衍射证明
Hiroki Kobayashi1, Kazuki Komatsu1, Hayate Ito1
1Geochemical Research Center, Graduate School of Science, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
研究人员发现了在高压Ice IV阶段气排序的证据. 这一发现揭示了一种低对称的有序状态,在这种转移稳定的冰形态中以前没有观察到.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 晶体学 晶体学是指结晶学.
背景情况:
- 冰IV是一个转移稳定的高压冰阶段,其特点是水分子的方向性障碍.
- 与其他冰相不同的是,对于冰IV,以前没有报道过方向排序.
研究的目的:
- 为了研究DCl-doped D2O ice IV.中的排序.
- 为了确定冰中是否存在一个排序状态, 第四阶段.
主要方法:
- 在现场粉末中子衍射实验在DCl-doped D2O ice IV.上进行.
- 瑞特维尔德精细化被用来分析晶体结构.
- 测量了单位细胞体积 (dV/dT) 的温度导数.
主要成果:
- 在120K左右观察到dV/dT的突然变化,表明相位过渡.
- 在低温下,一个稍微有序的结构被揭示出来.
- D1站点的占用率从0.5显著偏离,达到0.174{\displaystyle 0.174{\displaystyle 0.174}{\displaystyle 0.174}{\displaystyle 0.174}{\displaystyle 0.174}{\displaystyle 0.174}{\displaystyle 0.174}{\displaystyle 0.174}{\displaystyle 0.174}{\displaystyle 0.174}{\displaystyle 0.174}{\displaystyle 2.38}GPa和58K.
结论:
- 这项研究提供了证据,证明了冰IV中低对称的排序状态.
- 通过在高压下缓慢冷却来实现冰 IV 阶段的完整排序仍然具有实验挑战性.
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