通过密度功能理论和振动光谱学探索L-氨酸多态的稳定性和混乱性
John Kendrick1, Andrew David Burnett1
1University of Leeds, Leeds, LS2 9JT, United Kingdom.
Crystal growth & design
|August 7, 2023
概括
密度函数计算揭示了l-氨酸多态如何改变结构和键. 分子动力学模拟显示,在300 K的l-氨酸晶体中出现疾病.
科学领域:
- 计算化学是一种计算化学.
- 固态物理 固态物理
- 晶体学 晶体学是指结晶学.
背景情况:
- 在l-氨酸中的多态性影响其物理和化学特性.
- 了解晶体结构和动态对于材料科学应用至关重要.
研究的目的:
- 研究压力下的l-氨酸多态体的相对自由能量.
- 分析二面角在键图案中的作用.
- 在l-cysteine形式I中探索实验性障碍的模型.
- 预测光谱性质并与实验数据进行比较.
主要方法:
- 静态和动态密度函数理论 (DFT) 的计算.
- 自由能源计算的和近似.
- 分子动力学 (MD) 模拟.分子动力学 (MD) 模拟.
- 对二面角旋转和键过渡的分析.
- 红外 (IR) 和太赫兹 (THz) 吸收光谱的预测.
主要成果:
- 确定l-氨酸多态的相对自由能量作为压力的函数.
- 双面角旋转使S-H··S和S-H··O结基因之间的过渡成为可能.
- 对于每个多态形体,计算了二面角旋转的障碍.
- 研究了I形式的障碍模型 (域和分散).
- 模拟MD显示,在形式I和形式IV的300K时出现键障碍.
- 预测的IR和THz光谱与实验数据进行了比较.
结论:
- 二面角是l-氨酸多态的结构差异和结行为的一个关键因素.
- 在相关温度下,分散性障碍和动态键转换发生在l-氨酸晶体中.
- 计算预测与实验光谱保持一致,有助于理解疾病的影响.
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