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Title: Theoretical and experimental evaluation of the low m/z transmission of an electrodynamic ion funnel

Abstract

The transmission of ions at low m/z can be either necessary for an application or problematic (e.g. when large numbers of low m/z ions consume a large fraction of an ion trap’s capacity). The low m/z ion transmission limit of an electrodynamic ion funnel has been characterized using both experimental and theoretical approaches. A theoretical model is developed based on a series of infinite wire conductors that represent the ring electrodes of the ion funnel. Mathematical relationships for both low and high m/z cutoffs of the idealized two-dimensional system are derived. The low m/z cutoff is also evaluated through a series of experiments that show it is influenced by both the RF frequency and the DC electric field gradient. However, unlike multipole ion guides, there is no marked dependence of the low m/z cutoff on the RF amplitude, in agreement with theoretical results. With this new understanding, ion funnels can be designed and configured to better match the m/z range requirements for various applications.

Authors:
; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
878668
Report Number(s):
PNNL-SA-47277
Journal ID: ISSN 1044-0305; JAMSEF; 17797; 400412000; TRN: US200613%%123
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the American Society for Mass Spectrometry, 17(4):586-592; Journal Volume: 17; Journal Issue: 4
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CAPACITY; ELECTRIC FIELDS; ELECTRODES; ELECTRODYNAMICS; EVALUATION; MULTIPOLES; IONS; MATHEMATICAL MODELS; MASS SPECTROMETERS; Environmental Molecular Sciences Laboratory

Citation Formats

Page, Jason S., Tolmachev, Aleksey V., Tang, Keqi, and Smith, Richard D. Theoretical and experimental evaluation of the low m/z transmission of an electrodynamic ion funnel. United States: N. p., 2006. Web. doi:10.1016/j.jasms.2005.12.013.
Page, Jason S., Tolmachev, Aleksey V., Tang, Keqi, & Smith, Richard D. Theoretical and experimental evaluation of the low m/z transmission of an electrodynamic ion funnel. United States. doi:10.1016/j.jasms.2005.12.013.
Page, Jason S., Tolmachev, Aleksey V., Tang, Keqi, and Smith, Richard D. Sat . "Theoretical and experimental evaluation of the low m/z transmission of an electrodynamic ion funnel". United States. doi:10.1016/j.jasms.2005.12.013.
@article{osti_878668,
title = {Theoretical and experimental evaluation of the low m/z transmission of an electrodynamic ion funnel},
author = {Page, Jason S. and Tolmachev, Aleksey V. and Tang, Keqi and Smith, Richard D.},
abstractNote = {The transmission of ions at low m/z can be either necessary for an application or problematic (e.g. when large numbers of low m/z ions consume a large fraction of an ion trap’s capacity). The low m/z ion transmission limit of an electrodynamic ion funnel has been characterized using both experimental and theoretical approaches. A theoretical model is developed based on a series of infinite wire conductors that represent the ring electrodes of the ion funnel. Mathematical relationships for both low and high m/z cutoffs of the idealized two-dimensional system are derived. The low m/z cutoff is also evaluated through a series of experiments that show it is influenced by both the RF frequency and the DC electric field gradient. However, unlike multipole ion guides, there is no marked dependence of the low m/z cutoff on the RF amplitude, in agreement with theoretical results. With this new understanding, ion funnels can be designed and configured to better match the m/z range requirements for various applications.},
doi = {10.1016/j.jasms.2005.12.013},
journal = {Journal of the American Society for Mass Spectrometry, 17(4):586-592},
number = 4,
volume = 17,
place = {United States},
year = {Sat Apr 01 00:00:00 EST 2006},
month = {Sat Apr 01 00:00:00 EST 2006}
}
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