Miniature ion trap mass spectrometer enables mass-to-charge ratio analysis of ions via quadrupole field in a low vacuum environment. It plays an important role in on-site detection due to its portability and specificity. In order to gain a deeper understanding of the analysis mechanism of miniature ion trap mass spectrometers, a quadrupole MS ion trajectory numerical simulation model (QITNS) is established in this paper for ions trajectory calculation under the action of quadrupole field, exciting field and neutral gas molecule collision. Compared with the existing methods, the model in this paper is simpler and more direct, which effectively explored the effects of dipole excitation and quadrupole excitation on ion manipulation under high background pressure. The simulation results demonstrate that high RF amplitude, low auxiliary AC amplitude and quadrupole excitation can effectively improve the isolation resolution. Besides, it clarified the difference between the analysis mechanism of ion trap mass spectrometers under high background pressure (above 13.332 Pa) and absolute vacuum conditions. The relevant results are consistent with the conclusions of previous experiments and other theories, proving the applicability and accuracy of the proposed calculation model and solution method. This research bears the guiding significance for further understanding the mechanism of quadrupole mass spectrometry as well as designing and developing miniature mass spectrometers.

中文翻译：

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简单的数值模拟模型可以阐明设计小型化离子阱质谱仪的关键因素


微型离子阱质谱仪能够在低真空环境下通过四极场对离子进行质荷比分析。由于其便携性和特异性，在现场检测中发挥着重要作用。为了更深入地了解微型离子阱质谱仪的分析机理，本文建立了四极杆质谱离子轨迹数值模拟模型（QITNS），用于四极杆场、激励场和中性气体作用下的离子轨迹计算分子碰撞。与现有方法相比，本文的模型更加简单、直接，有效地探讨了偶极子激发和四极子激发对高背景压力下离子操控的影响。仿真结果表明，高射频幅度、低辅助交流幅度和四极激励可以有效提高隔离分辨率。此外，还阐明了离子阱质谱仪在高背景压力（13.332 Pa以上）和绝对真空条件下分析机制的差异。相关结果与前期实验和其他理论的结论一致，证明了所提出的计算模型和求解方法的适用性和准确性。该研究对于进一步认识四极杆质谱的机理以及设计和开发微型质谱仪具有指导意义。