晶体学证据表明氧离子受体在氧离子键中的方向性
Benjamin P Hay1, David A Dixon, Jeffrey C Bryan
1W. R. Wiley Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352, USA. ben.hay@pnl.gov
Journal of the American Chemical Society
|January 10, 2002
概括
这项研究揭示了在晶体结构中涉及氧离子的键的明显方向偏好. 这些键的方向性受到氧离子离子的影响.
科学领域:
- 晶体学 晶体学是指结晶学.
- 无机化学 无机化学
- 计算化学的计算化学
背景情况:
- 键在分子相互作用和晶体工程中至关重要.
- 键受体的几何结构会影响它们的相互作用偏好.
- 氧离子在生物系统和材料科学中很普遍.
研究的目的:
- 研究涉及氧离子受体的键的方向偏好.
- 为了将观察到的键方向性与氧离子几何学相关联.
- 将实验结果与理论静电电位计算进行比较.
主要方法:
- 在晶体结构中分析2632个D-H...O-A键.
- 基于三角平面和四面体的氧化离子几何学的键的分类.
- 对代表性氧离子的静电电位面的计算.
主要成果:
- 在oxyanions中的氧原子接受器中建立了键的独特方向性.
- 三角形平面氧化离子 (例如,酸盐,碳酸盐) 显示平均H...O-A角度为115°,在平面内偏好.
- 四面体氧化离子 (例如,酸盐,硫酸盐) 的平均H...O-A角度为122°,对被遮蔽的二面体角度的偏好很弱.
- 观察到的方向性与计算的静电电位面上的最小值保持一致.
结论:
- 氧离子几何学决定了键受体的方向性.
- 与氧离子的结合表现出可预测的方向偏好.
- 静电电位图准确地预测观察到的键方向性.
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