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パラセタモールのポリモルフの予測,形態,および機械的性質
1Centre for Theoretical and Computational Chemistry, Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, United Kingdom.
Journal of the American Chemical Society
|July 18, 2001
まとめ
研究者はパラセタモール (アセトアミノフェン) の結晶構造を予測し,安定した形態と多くの可能なポリモルフを特定しました. 弾性特性と成長形態学は,特徴のない形態の候補者を絞り込むのに役立ちました.
科学分野:
- 固体化学 固体化学
- マテリアルサイエンス 材料科学
- 計算化学はコンピュータ化学である.
背景:
- パラセタモール (アセトアミノフェン) は,複数の結晶形 (ポリモルフ) で存在します.
- 既知のポリモルフには,安定した形態と,有利な錠剤形成特性を持つ変形安定した形態が含まれています.
- パラセタモールの特徴のない転移性ポリモルフも報告されています.
研究 の 目的:
- パラセタモールの潜在的な結晶構造を,格子エネルギー最小化を使用して体系的に予測する.
- 実験的に重要なポリモルフと仮説的な構造を区別するための基準を特定する.
- 特徴づけられていないパラセタモールポリモルフの候補者を調査する.
主な方法:
- 格子エネルギー最小化を使用して結晶構造の予測.
- 第2導関数解析による弾性特性の推定.
- 結合エネルギーモデルを用いた蒸気成長形態の評価.
主要な成果:
- 安定したモノクリン型パラセタモールポリモルフは,地球規模の格子エネルギー最小値として特定されました.
- 12以上のエネルギー的に実現可能な仮説的な結晶構造が予測されました.
- 弾性特性と成長形態学の計算は,既知の多形体の実験データと合理的な一致を示した.
- 予測されたいくつかの構造は,低い成長率または機械的な安定性が低いため,可能性が低いと判断されました.
結論:
- 計算方法により,パラセタモールのポリモルフを効果的に予測できます.
- 弾性や形状などの物理的性質を組み込むことは,仮説的な構造をフィルタリングするのに役立ちます.
- この研究では,特徴づけられていないパラセタモールポリモルフの潜在的な候補者を特定し,さらなる調査を正当化しました.
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