金属ガラスのイコサヘドンの幾何学的な挫折
1WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
Science (New York, N.Y.)
|July 13, 2013
まとめ
ローカル・アイコサヘドラル・オーダー,金属のガラスの原子構造は,長い間理論化されてきましたが,実験的に観察されています. これらのアイコサヘドラは歪みがあり,金属ガラス構造における幾何学的挫折の証拠を提供します.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- クリスタログラフィーです.
背景:
- 超冷却液体や金属ガラスにおける支配的な原子モチーフとして,イコサヘドラル秩序が仮説化されている.
- イコサヘドラの密集した性質は,構造的な挫折と翻訳周期性の欠如による成長の困難と対照的です.
研究 の 目的:
- 実験的に観測し,金属のガラスでローカル・アイコサヘドラル・オーダーを特徴づける.
- これらの観察されたイコサヘッドの幾何学的な性質と対称性を調査するために.
主な方法:
- アングストロム-ビーム電子 difraktion (ABED) を利用する.
- 金属ガラスのサンプル内の個々のイコサヘドラの difraktion パターンを分析する.
主要な成果:
- 金属のガラスでローカル・アイコサヘドール・オーダーの実験的確認.
- すべての検出されたイコサヘドラが歪みを示す観察.
- 歪んだイコサヘッドラ内の部分面中心立方体 (FCC) 対称性の識別.
結論:
- メタリックグラスにおけるローカル・アイコサヘドラル・オーダーの存在を裏付ける直接的な実験的証拠を提供する.
- 幾何学的挫折が金属ガラスの局所的な原子配列に大きく影響することを示した.
- これらのicosahedralクラスターの歪んだ,部分的にFCC対称な性質を強調しています.
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