温度依赖的固态相位过渡,在4-甲基-氧-化的晶体结构中发生结合
Rao M Uppu1, Sainath Babu1, Frank R Fronczek2
1Department of Environmental Toxicology, Southern University and A&M College, Baton Rouge, LA 70813, USA.
Acta crystallographica. Section E, Crystallographic communications
|February 5, 2024
概括
这项研究揭示了结晶盐 (C7H10NO+·Cl−) 在冷却时的相变. 过渡改变了晶体结构和结合,影响了分子排序和薄膜传播.
科学领域:
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
- 材料科学是一种材料科学.
背景情况:
- 标题盐 (C7H10NO+·Cl−) 在室温下表现出一个正方体结构.
- 之前的晶体学数据报告了在室温下Z'=1的正方体空间组Pbca.
- 固态相位过渡对于理解不同条件下的材料特性和行为至关重要.
研究的目的:
- 为了研究室温和100K之间的标题盐的结构变化和相位过渡.
- 为了描述高温 (250 K) 和低温 (100 K) 晶体结构.
- 分析相变对结和分子排列的影响.
主要方法:
- 采用单晶X射线衍射来确定250K和100K的晶体结构.
- 分析结晶学数据,包括空间组,单元细胞参数和原子坐标.
- 通过结构分析研究结网络和分子构造.
主要成果:
- 在250K和200K之间发生固态相过渡,将结构从正方体 (Pbca) 转变为单临床 (P21/c),Z'=2.2.
- 在低温结构中, (NH3) 原子是有序的,在独立的分子中具有不同的方向,优化N-H···Cl键.
- 在高温结构中,的原子是无序的,甲氧基团与分子几乎保持共平面.
结论:
- 阶段过渡显著影响了组和键网络的排序.
- 观察到的结构变化归因于优化分子间相互作用,特别是N-H···Cl键.
- 该研究提供了详细的结构洞察力,了解结晶盐的温度依赖性行为.
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