在金属玻璃中的二元面体的几何挫折
1WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
概括
实验证实了局部的二面体秩序,一个长期理论化的金属玻璃中的原子结构. 这些二面板被扭曲,提供了金属玻璃结构中几何挫折的证据.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 晶体学 晶体学是指结晶学.
背景情况:
- 在超冷液体和金属玻璃中,Icosahedral顺序被假设为主导的原子图案.
- 伊科萨赫德拉的密集性与其由于结构挫折和缺乏翻译周期性的生长困难形成鲜明对比.
研究的目的:
- 在金属玻璃中实验性地观察和描述当地的二面面体秩序.
- 为了研究这些观测到的二元树木的几何性质和对称性.
主要方法:
- 使用安格斯特罗姆束电子衍射 (ABED).
- 分析金属玻璃样本中的单个icosahedra的衍射模式.
主要成果:
- 在金属玻璃中实验证实了局部的二面体顺序.
- 观察到所有检测到的icosahedra都表现出扭曲.
- 在扭曲的icosahedra中识别部分面中心立方对称 (FCC).
结论:
- 提供了直接的实验证据,支持在金属玻璃中存在局部二面面体秩序.
- 证明几何挫折显著影响金属玻璃中的局部原子排列.
- 突出了这些二元正面星团的扭曲,部分FCC对称性.
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