title: Determination of E/N Influence on K0Values within the Low Field Region of Ion Mobility Spectrometry.
abstract: The established theory of ion motion within weak electric fields predicts that reduced ion mobility (K0) remains constant as a function of the ratio of electric field strength to drift gas number density (E/N). However, upon increasing the accuracy and precision of K0value measurements during a previous study, a new relationship was seen in which the K0values of ions decreased as a function of increasing E/N at field strengths below 4 Td. Here the effect of E/N on the K0value of an ion has been investigated in order to validate the reality of the phenomenon and determine its cause. The pertinent measurements of voltage and drift time were verified in order to ensure the authenticity of the trend and that it was not a result of a systematic error in parametric measurements. The trend was also replicated on a separate ion mobility spectrometer drift tube in order to further validate its authenticity. As a result, the theory of ion motion within weak electric fields should be revised to reflect the behavior seen here.
authors.affiliation: Department of Chemistry, Washington State University , 305 Fulmer Hall, Pullman, Washington 99164, United States.
authors.forename: Brian C
authors.identifier: http://orcid.org/0000-0002-1054-0575
authors.initials: BC
authors.lastname: Hauck
authors.affiliation: Department of Chemistry, Washington State University , 305 Fulmer Hall, Pullman, Washington 99164, United States.
authors.forename: William F
authors.initials: WF
authors.lastname: Siems
authors.affiliation: LEIDOS-U.S. Army Edgewood Chemical Biological Center Operations , P.O. Box 68, Gunpowder, Maryland 21010, United States.
authors.forename: Charles S
authors.initials: CS
authors.lastname: Harden
authors.affiliation: U.S. Army Edgewood Chemical Biological Center , Aberdeen Proving Ground, Maryland 21010, United States.
authors.forename: Vincent M
authors.initials: VM
authors.lastname: McHugh
authors.affiliation: Department of Chemistry, Washington State University , 305 Fulmer Hall, Pullman, Washington 99164, United States.
authors.forename: Herbert H
authors.initials: HH
authors.lastname: Hill