Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka, 558-8585, Japan.
Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, 599-8531, Japan.
Chemphyschem. 2020 May 5;21(9):847-852. doi: 10.1002/cphc.202000021. Epub 2020 Mar 19.
A multiply charged molecule expands the range of a mass window and is utilized as a precursor to provide rich sequence coverage; however, reflectron time-of-flight mass spectrometer has not been well applied to the product ion analysis of multiply charged precursor ions. Here, we demonstrate that the range of the mass-to-charge ratio of measurable product ions is limited in the cases of multiply charged precursor ions. We choose C F as a model molecule to investigate the reactions of multiply charged molecular cations formed in intense femtosecond laser fields. Measurements of the time-of-flight spectrum of C F by changing the potential applied to the reflectron, combined with simulation of the ion trajectory, can identify the species detected behind the reflectron as the neutral species and/or ions formed by the collisional charge transfer. Moreover, the metastable ion dissociations of doubly and triply charged C F are identified. The detection of product ions in this manner can diminish interference by the precursor ion. Moreover, it does not need precursor ion separation before product ion analysis. These advantages would expand the capability of mass spectrometry to obtain information about metastable ion dissociation of multiply charged species.
多电荷分子扩展了质量窗口的范围，并被用作前体，以提供丰富的序列覆盖；然而，反射飞行时间质谱仪尚未很好地应用于多电荷前体离子的产物离子分析。在这里，我们证明了在多电荷前体离子的情况下，可测量产物离子的质荷比范围是有限的。我们选择 CF 作为模型分子，研究在强飞秒激光场中形成的多电荷分子阳离子的反应。通过改变反射器上施加的电势来测量 CF 的飞行时间谱，并结合离子轨迹的模拟，可以识别出反射器后面检测到的物质是中性物质和/或通过碰撞电荷转移形成的离子。此外，还鉴定了双电荷和三电荷 CF 的亚稳离子解离。以这种方式检测产物离子可以减少前体离子的干扰。此外，在进行产物离子分析之前，不需要对前体离子进行分离。这些优势将扩展质谱法获取关于多电荷物质亚稳离子解离信息的能力。
