構造ガラス形成器の原子モデルにおけるダイナミック・オーダー・ディソードー
Lester O Hedges1, Robert L Jack, Juan P Garrahan
1Department of Chemistry, University of California, Berkeley, CA 94720-1460, USA.
まとめ
構造ガラスの形成物における第1次動的相変異の証拠を発見しました. この移行は軌道空間で起こり,ガラスの現象の理解を統一します.
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
- コンピューティング・ケミストリー
背景:
- 構造的秩序のない液体から固体への変化であるガラスの移行は,実験的に観察されているが,理論的に議論されている.
- ガラス変遷が真の相変遷であるという性質は,凝縮物質物理学の論争の的課題である.
研究 の 目的:
- ガラスの移行に関連した新しいタイプの相変化の数値的な証拠を提供するために.
- 構造ガラス形成器の原子モデルにおけるダイナミックな相変化の存在を調査する.
主な方法:
- 構造ガラスの形状をモデル化するために,原子学的シミュレーションを使用します.
- コンフィギュレーション空間ではなく,軌道空間でのシステム動態の分析.
- システムを均衡状態から外す条件を特定する.
主要な成果:
- ガラスの造形器の第1次動的相変異に関する数学的証拠を提示した.
- この移行が軌道の空間で起こることが示され,均衡段階の移行とは異なる.
- エルゴディック (移動) 段階とノンエルゴディック (不移動) 段階の共存が確立された.
結論:
- ガラスの移行は,真の相変化として理解することができます.
- このダイナミックな相変化は,ガラスのような現象のための統一された枠組みを提供します.
- 実験的観測と理論的な相変化の概念を結びつける.
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