在2-基乙基酸离子液体系统中的负电荷集群的动力学和热化学
Wenjing Zhou1,2, Jianbo Liu1,2, Steven D Chambreau3
1Department of Chemistry and Biochemistry, Queens College of the City University of New York, 65-30 Kissena Blvd., Queens, New York 11367, USA. jianbo.liu@qc.cuny.edu.
Physical chemistry chemical physics : PCCP
|August 2, 2024
概括
负电荷的2-基乙基酸集群表现出与负电荷的对应物相似的形成和碎片化模式. 关键途径涉及离子对损失和质子转移,解离发生在低能 (<1.5 eV).
科学领域:
- 物理化学 物理化学
- 化学物理 化学物理
- 离子液体研究 离子液体研究
背景情况:
- 离子液体 (ILs) 是100°C以下液态的盐,具有调节性质.
- 了解集群形成和碎片化对于IL应用至关重要.
- 之前的研究探讨了带正电荷的IL集群;这项工作研究了负电荷的对应物.
研究的目的:
- 为了研究负电荷的2-基乙基酸 ([HOCH2CH2NH2NH2]+NO3-,HEHN) 离子液体集群的形成和碎片化机制.
- 为了比较负电荷的HEHN星团与先前报告的正电荷星团的行为.
- 确定这些离子液体集群的结构和热力学特性.
主要方法:
- 使用 Xe 原子进行引导离子束并列质谱与碰撞诱导解离.
- 集群离子组成和解离产物的质量分析.
- 分子动力学模拟和DFT计算 (ωB97XD/6-31+G(d,p)) 用于结构识别和热力学分析.
主要成果:
- 主要观察到的集群离子的质量电荷比 (m/z) 低于350.
- 主要的碎片化途径涉及中性HEHN离子对的损失.
- 内离子对质子转移导致2-基乙基和HNO3的消除是一个重要的次要途径.
- 所有观测到的星团在低于1.5 eV的值能量时分离.
结论:
- 与正电荷集群相比,负电荷的HEHN集群在形成和碎片化学方面表现出了显著的相似之处.
- 这些相似之处归因于HEHN离子液体固有的离子性质和高电导率.
- 这些发现提供了关于阳性和负电荷状态下的离子液体集群的基本行为的见解.
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