RELATIVE DISSOCIATION-ENERGY MEASUREMENTS USING ION-TRAP COLLISIONAL ACTIVATION
RELATIVE DISSOCIATION-ENERGY MEASUREMENTS USING ION-TRAP COLLISIONAL ACTIVATION
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DOI：
10.1016/1044-0305(94)85015-1
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发表时间：
1994-04-01
影响因子：
3.2
通讯作者：
MCLUCKEY, SA
中科院分区：
文献类型：
--
作者：
HART, KJ;MCLUCKEY, SA
四极离子阱碰撞激活实验中多原子离子分解的最小共振激发幅值与文献中的临界能量相对应。本文描述了如何通过四极离子阱中与碰撞诱导离解（即离解速率常数）相关的动力学来推导阈值共振激发振幅的实验。这些阈值与临界能之间的关系是通过使用其他技术测量临界能的分子离子获得的动力学数据来建立的。由于高阶场的影响，最佳共振激励频率随幅值的变化使实验变得复杂。有人提出，阈值共振激发幅值是达到可测量的分解速率所需的母离子群温度变化的量度。目前的结果表明，四极离子阱作为气体离子化学研究的定量工具可能会有新的应用。
The measured minimum resonance excitation amplitudes for decomposition of polyatomic ions in the quadrupole ion trap collisional activation experiment are shown to correlate with literature critical energies. The present article describes how experiments can be performed to derive threshold resonance excitation amplitudes via the kinetics associated with collision-induced dissociation (i.e., dissociation rate constants) in the quadrupole ion trap. The relationship between these threshold values and critical energies is established empirically by using kinetic data acquired for molecular ions with critical energies measured with other techniques. The experiments are complicated by the change in optimum resonance excitation frequency with amplitude, due presumably to contributions from higher order fields. It is proposed that the threshold resonance excitation amplitude is a measure of the change in temperature of the parent ion population required to achieve a measurable rate of decomposition. The present results indicate that the quadrupole ion trap may see new applications as a quantitative tool for the study of gaseous ion chemistry.