Differential Ion Mobility Spectrometry: Nonlinear Ion Transport and Fundamentals of FAIMS

Over the last decade, scientific and engineering interests have been shifting from conventional ion mobility spectrometry (IMS) to field asymmetric waveform ion mobility spectrometry (FAIMS). Differential Ion Mobility Spectrometry: Nonlinear Ion Transport and Fundamentals of FAIMSexplores this new analytical technology that separates and characterizes ions by the difference between their mobility in gases at high and low electric fields. It also covers the novel topics of higher-order differential IMS and IMS with alignment of dipole direction.The book relates the fundamentals of FAIMS and other nonlinear IMS methods to the physics of gas-phase ion transport. It begins with the basics of ion diffusion and mobility in gases, covering the main attributes of conventional IMS that are relevant to all IMS approaches. Building on this foundation, the author reviews diverse high-field transport phenomena that underlie differential IMS. He discusses the conceptual implementation andfirst-principles optimization of FAIMS as a filtering technique, emphasizing the dependence of FAIMS performance metrics on instrumental parameters and properties of ion species. He also explores ion reactions in FAIMS caused by field heating and the effects of inhomogeneous electric field in curved FAIMS gaps. Written by an accomplished scientist in the field, this state-of-the-art book supplies the foundation to understand the new technology of nonlinear IMS methods.

Separation and Characterization of Molecules and Ions Using Gas-Phase Transport Physical Foundation and Definitions Characterization of Molecules by Diffusion Measurements IMS: Ion Dynamics in IMS and Consequent General Features Relating IMS Data to Molecular Structure Fundamentals of High-Field Ion Mobility and Diffusion General Aspects of High-Field Ion Mobility: Standard and Nonstandard Effects Standard High-Field Effect Clustering of Gas Molecules on Ions and Standard High-Field Effect Non-Blanc Phenomena in High-Field Ion Transport Vibrationally Inelastic Collisions Rotational Inelasticity and Collisional Alignment of Ions Dipole Alignment of Ions Unstable High-Field Mobility of Runaway Ions Summary and Significance for Differential IMS Conceptual Implementation of Differential IMS and Separation Properties of FAIMS Strategy for Optimum Differential Ion Mobility Separations Limitations on the Differential IMS Paradigm That Shape FAIMS Approach Trends of FAIMS Separation Parameters Separations in Heteromolecular Media Ion Transformations inside FAIMS and Effect on Separation Performance Separation Performance of FAIMS and Its Control via Instrumental Parameters Approaches to Simulation of FAIMS Operation Separation Properties in Homogeneous Electric Field Ion Focusing in Inhomogeneous Fields and Consequences for FAIMS Performance Beyond FAIMS: New Concepts in Nonlinear Ion Mobility Spectrometry Ion Guidance and Trapping at Atmospheric Pressure Higher-Order Differential (HOD) IMS Methods Ion Mobility Spectrometry with Alignment of Dipole Direction (IMS-ADD) Index References appear at the end of each chapter.