阴离子诱导的变化导致了加密子的结构变化
Oscar H Lloyd Williams1, Claudia S Cox1, Meng Yuan Zhang1
1School of Chemistry, UNSW Sydney, Sydney, NSW, 2052, Australia. n.rijs@unsw.edu.au.
Dalton transactions (Cambridge, England : 2003)
|October 1, 2024
概括
抗密素与的复合物显示出惊人的尺寸变化. 气相研究揭示了影响封装和结构趋势的竞争物理效应.
科学领域:
- 超分子化学 超分子化学
- 物理化学 物理化学
- 分析化学 分析化学
背景情况:
- 隐形生物是能够封装客物种的宏环分子.
- 了解宿主-客人相互作用对于分子识别和传感至关重要.
- 气相研究为复杂的形成提供了独特的见解,这与凝结相行为不同.
研究的目的:
- 为了研究抗密度的气相复杂化与各种单离子客体.
- 用离子移动性质谱法确定这些复合物的结构趋势和封装机制.
- 为了比较气相发现与冷凝相复杂化数据.
主要方法:
- 使用高分辨率离子移动性质谱法 (HR-IM-MS) 来测量移动性,并推导出阴离子加密复合体的碰撞截面.
- 密度函数理论 (DFT) 的计算被用来建模和确认封装路径.
- 同热度定位热度计 (ITC) 和其他凝聚相技术提供了比较数据.
主要成果:
- 观察到结构收缩的悖论趋势,大多数金属和酸的离子体大小增加.
- 电离子 (Li+) 显示出更喜欢链接协调而不是完全封装,从而产生更大的结构.
- 与阴离体复合体相比,质子化体形成了显著更大的,爆破的结构.
- 气相结果证实了缩相研究中观察到的趋势.
结论:
- 相互竞争的物理效应,包括离子大小,协调偏好和加密结构灵活性,决定了复合物的观察到的非周期性大小趋势.
- 由DFT支持的气相实验数据,提供了对加密封封装机制的详细了解.
- 这项研究强调了HR-IM-MS在阐明气相中宿主-客人相互作用中的实用性.
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