酸作为质子水集群中的客分子:对I(H2O) n+的FT-ICR/DFT联合研究
1Institut für Physikalische und Theoretische Chemie, Technische Universität München, Lichtenbergstrasse 4, 85747 Garching, Germany.
Journal of the American Chemical Society
|June 21, 2001
概括
阴离子-水集群的碎片化率随着大小的增加而增加. 这些聚合物与HCl反应,形成合物,与阴离子聚合物不同,并揭示了对质子水结构的洞察力.
科学领域:
- 物理化学 物理化学
- 化学物理 化学物理
- 频谱学是一种光谱学.
背景情况:
- 研究水合离子的行为为溶解动力学提供了基本的见解.
- 了解集群离子结构对于模拟各种环境中的化学反应至关重要.
研究的目的:
- 描述阴离子-水团I(H2O) n+的结构和反应性.
- 为了比较阴离子-水集群与它们的阳离子对应物的特性.
主要方法:
- 使用激光蒸发源生成阴离子-水集群.
- FT-ICR质谱分析集群组成和碎片化.
- 在无碰撞条件下研究黑体辐射诱导的碎片化.
- 密度函数计算以建模集群结构和能量学.
主要成果:
- 单分子碎片化速率常数与I(H2O) n+,n = 3-15的集群大小线性增加.
- 阴离子团I(H2O) n+,n > 13,与HCl反应形成ICl和质子化水团.
- 密度函数计算显示,I(H2O) n+集群最好被描述为具有低酸部分的质子水集群.
结论:
- 阴离子-水团的碎片化行为取决于大小,与其他水合离子相似.
- 与HCl的反应突出了阴离子和阳离子-水集团化学之间的差异.
- 阴离子集群的结构涉及质子化酸,在H2IO+和H4IO2+核心离子之间进行过渡.
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