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Microfluidic Preparation of Liquid Crystalline Elastomer Actuators
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形を維持する単結晶から無形から単結晶の多形変換は可能である
Olivier Renier1, Guillaume Bousrez1, Glib V Baryshnikov2,3
1Department of Materials and Environmental Chemistry, Stockholm University, 10691 Stockholm, Sweden.
Journal of the American Chemical Society
|November 23, 2021
まとめ
亜鉛塩化物複合体などの結晶性物質の多形相移行は,現在詳細に研究することができます. 形状を保全する ゆっくりとした変化を観察しました 形状を保全する ゆっくりとした変化を観察しました 形状を保全する ゆっくりとした変化を観察しました
科学分野:
- 固体化学
- クリスタルグラフィー
- 材料科学
背景:
- 結晶物質はしばしば多形体として存在し,温度や圧力の変動で固体から固体への移行を経験します.
- これらの多形変換の正確なメカニズムを理解することは,それらの典型的急速な速度のために重要な課題です.
- 現在の力学的な洞察は,往々にして,移行前の結晶構造と移行後の結晶構造を比較することによって推論され,詳細な理解を制限しています.
研究 の 目的:
- 結晶物質における多形相変異のメカニズムを研究する.
- 形を維持する多形変異の過程で結晶性が維持されるという一般的な仮定に異議を唱える.
- 固体-固体変換における中間相の役割を解明する.
主な方法:
- シングルクリスタルX線微分分析
- ZnCl2 ((1,3-ディエチリミダゾール-2-チオン) 2ポリモルフにおけるゆっくりとした固体相移行の観察
- 中間無形相の特徴
主要な成果:
- ZnCl2 ((1,3-ディエチリミダゾール-2-チオン) 2の多形変異は異常なほど遅いことが観察された.
- 変形は無形な中間段階を経て進行した.
- 形状の保存は単結晶から単結晶の変換まで維持された.
結論:
- この研究は,無形な中間物質を含む多形相移行の新しいメカニズムを明らかにしています.
- この発見は,形を維持する固体-固体変換の間に結晶性が保たれているという長年の見解に異議を唱える.
- この特定の移行の遅さは,以前には達成できなかった詳細なメカニズム的な洞察を可能にしました.
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