从电喷气电离到冷喷气电离:如何评估气态离子的冷却效应?
Emilie Bertrand1, David Rondeau1, Thomas Delhaye1
1Univ Rennes, CNRS, IETR - UMR 6164, Rennes, France.
Journal of mass spectrometry : JMS
|October 30, 2023
概括
两种用于测量离子内部能量的方法进行了比较. 冷喷离子化 (CSI) 与电喷离子化 (ESI) 相比,显著冷却离子,特别是在甲醇中.
科学领域:
- 分析化学 分析化学
- 物理化学 物理化学
- 质谱测量质量谱测量
背景情况:
- 了解气态离子的内部能量对于解释质谱实验至关重要.
- 电喷离子化 (ESI) 和冷喷离子化 (CSI) 是生产离子的常见方法,但它们的能量特性不同.
- 源内碰撞诱导解离 (CID) 是激活离子碎片化和研究其能量的一个关键过程.
研究的目的:
- 研究两种生存产量 (SY) 测量方法,用于评估气态离子的平均内部 (
) 和热 ( ) 能量. - 为了比较ESI和CSI产生的离子的热特性.
- 评估溶剂选择 (甲醇与乙二) 对CSI中的离子温度的影响.
主要方法:
- 研究了两个SY测量方法:内部能量分布 (P(Eint)) 作为Sigmoid导数和MassKinetics软件建模.
- 使用替代的酸和来源的CID用于离子激活.
- 在不同的溶解电压下测量振动温度 (Tvib) 和特征温度 (Tchar) 参数.
主要成果:
- 在离子内部/热能和孔1电压之间发现了线性相关性.
- 推断到零电压表明,在ESI (~650K) 中的离子比CSI (~300K) 更热.
- 与甲醇的CSI导致较大的离子冷却与乙二相比,与ESI不同.
结论:
- 调查的两种方法都有效地评估了离子内部和热能.
- 与ESI相比,CSI对气态离子提供了显著的冷却效应.
- 溶剂的选择会影响CSI中的离子冷却,甲醇比乙二更有效.
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