首页>
外国专利>
Method of operating quadrupoles with added multipole fields to provide mass analysis in islands of stability
Method of operating quadrupoles with added multipole fields to provide mass analysis in islands of stability
展开▼
机译:在增加的多极场中运行四极以在稳定岛中提供质量分析的方法
展开▼
页面导航
摘要
著录项
相似文献
摘要
A method of processing ions in a quadrupole rod set us provided. The method comprises a) establishing and maintaining a two-dimensional substantially quadrupole field for processing the ions, the field having a quadrupole harmonic with amplitude A2 and a selected higher order harmonic with amplitude Am wherein m is an integer greater than 2, and the magnitude of Am is greater than 0.1% of the magnitude of A2; b)introducing the ions to the two-dimensional substantially quadrupole field and subjecting the ions to both the quadrupole harmonic and the higher order harmonic of the field to radially confine ions having Mathieu parameters a and q within a stability region defined in terms of the Mathieu parameters a and q; c) adding an auxiliary excitation field to transform the stability region into a plurality of smaller stability islands defined in terms of the Mathieu parameters a and q; and, d) adjusting the two-dimensional substantially quadrupole field to place ions within a selected range of mass-to-charge ratios within a selected stability island in the plurality of stability islands to impart stable trajectories to the selected ions within the selected range of mass-to-charge ratios for transmission through the rod set, and to impart unstable trajectories to unselected ions outside of the selected range of mass-to-charge ratios to filter out such ions.
展开▼