Application of mobility theory to the interpretation of data generated by linear and RF excited ion mobility spectrometers

The theory of operation for linear and radio-frequency (RF)-ion mobility spectrometer (IMS) is briefly summarized. The operation of the linear IMS is best described by the continuity equation, and the operation of the RF-IMS is best described by the momentum balance equation. Simple relationships for the RF-IMS show that the compensation field is directly proportional to ion mobility, along with the cube of the dispersion field. When the relationships are applied to the analysis of field-asymmetric ion mobility spectrometry (FALMS) data collected on a chloride ion, the ion is found to be non-converting (i.e., not clustered with water or nitrogen adducts). For this reason, the chloride ion might be used under controlled conditions to anchor the mobility scale for RF-IMS. Contributions of the electric field to the effective ion temperature influence not only the mobility of the ion, but also its cluster activity. (Int J Mass Spectrom 214 (2002) 95-104) (C) 2002 Published by Elsevier Science B.V.