溶液から結晶化した2,4,6-トリニトロトールエンの多形性
R M Vrcelj1, H G Gallagher, J N Sherwood
1Contribution from the Department of Pure and Applied Chemistry and Department of Physics and Applied Physics, University of Strathclyde, Glasgow G1 1XL, Scotland, UK.
Journal of the American Chemical Society
|July 18, 2001
まとめ
溶媒のタイプは,構造的指針によってではなく,溶解性や超飽和性に影響を及ぼし,異なる結晶形に導いて,2,4,6-トリニートロトルエーネ (TNT) のポリモルフィズムに影響します. これはオストワルドと一致する.
科学分野:
- 結晶化科学 結晶化科学とは
- 材料化学 材料化学について
- 物理化学 物理化学
背景:
- 2,4,6-トリニトロトールーエン (TNT) の多形性は,その安定性および特性にとって重要である.
- 以前の研究では,溶媒の種類がTNTの多形形状を直接決定することを示唆していた.
- 溶媒の効果を理解することは,結晶化プロセスを制御する鍵です.
研究 の 目的:
- 2,4,6-トリニトロトルーエン (TNT) 降水のポリモルフィック性における溶媒タイプの役割を調査する.
- 溶媒のステレオ特異的誘導または溶解性が多形的な結果を決定するかどうかを判断する.
- TNTおよび関連化合物のメタステーブル形態を分離するための規則を定めること.
主な方法:
- 様々な溶媒から2,4,6-トリニトロトールエーン (TNT) の降水.
- 段階移行を研究するためのカロリメトリック技術.
- 構造分析のためにシンクロトロン放射を用いたインシットゥ・クリスタライゼーション研究.
主要な成果:
- ポリモルフ的変異は,溶解性および超飽和度に関連しており,直接的な溶媒構造指針ではありません.
- メタステーブルなオーソロンビック相が最初に沈殿し,その後,安定したモノクリニック形態への変換が続きます.
- 溶媒媒介相変換は,溶解性と運動学によって影響を受けます.
結論:
- TNTのポリモルフィズムに対する溶媒の効果は,主に運動性および溶解性によるものであり,ステレオ特異的ではありません.
- 結果はオストワルドの段階法則と一致し,転移安定形態の初期降水を説明しています.
- 策定されたルールは,関連系における,元安定ポリモルフ形態の分離を導くことができる.
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