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化甲酸集群及其与电子的相互作用

Kevin Li¹, Jozef Ďurana², Barbora Kocábková²

¹Lehrstuhl für Physikalische Chemie, TUM School of Natural Sciences, Technische Universität München, Lichtenbergstraße 4, 85748, Garching, Germany.

Chemphyschem : a European journal of chemical physics and physical chemistry

|February 19, 2024

概括

研究与水合甲酸 (FA) 集群的电子相互作用,揭示了不同的离子形成路径. 电子电离主要产生质子离子,而电子附着显示大小和能量依赖的碎片化,影响集群组成分析.

科学领域:

物理化学物理化学
化学物理化学物理
材料科学材料科学材料科学

背景情况:

了解水合集群的行为对于各种化学和物理过程至关重要.
酸 (FA) 和水集群作为研究溶解和电离现象的模型系统.
电子-物质相互作用是许多化学反应和分析技术的基础.

研究的目的:

为了研究在化甲酸 (FA) 集群中在电子冲击时的离子形成.
阐明电子电离 (EI) 和电子附着 (EA) 下的离子形成和碎片化的机制.
确定集群大小,水化水平和电子能量对离子光谱和集群组成分析的影响.

主要方法:

使用可变能量的电子在水合甲基酸集群中对离子形成的实验研究.
专注于70 eV的电子电离 (EI) 和1.515 eV的低能电子附着 (EA).
对正负离子质谱的分析,以确定碎片离子和评估集群组成.

主要成果:

电子电离 (EI) 主要在富含FA的星团中产生质子化[FAm+H]+离子和稳定的环结构,围绕H3O+形成.
低能电子附着 (EA) 有利于完整的[FAm·Wn]−离子的形成,而更高的能量则促进了对[FAm·Wn-H]−的碎片化.
集群内部的离子-分子反应会影响更高电子能量的碎片化路径.
集群中的水蒸发高度依赖于电离方法,这使得从质谱中计算中性集群大小的估计变得复杂.

结论:

电离方法显著决定了水合甲基酸集群中的离子形成路径和碎片化模式.
富含FA的星团的质谱可以提供对其大小和组成的见解,但必须考虑水蒸发的影响.
从质谱中准确确定中性水合集群大小是具有挑战性的,因为依赖于电离的水损失.

关键词:

通过键结合,形成键.离子-分子反应是离子-分子反应.电离化的电离.质谱测量质谱测量质谱测量质谱测量质量测量质谱测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量质量测量溶剂的作用是溶剂的作用.

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