Properties and performance of a quadrupole mass filter used for resonance ionization mass spectrometry

The performance of commercial quadrupole mass spectrometers (QMS) with a nu mber of imperfections, as compared to the ideal hyperbolic geometry, has be en characterized using the computer simulation program SIMION 3D version 6. 0. The analysis of simulated QMS geometries focuses primarily on modeling o f the internal potential, the study of field deviations, and the influence of finite length on performance of the QMS. The computer simulation of ion trajectories in the QMS field yields predictions for optimum working condit ions and provides estimates for the resolving power and the maximum isotopi c abundance sensitivity. Experimental measurements that confirm these expec tations are presented. Optimization of the geometry and various operational parameters of the QMS is an important step in the development of a system for highly selective ultratrace determination using laser-based resonance i onization mass spectrometry. (Int J Mass Spectrom 181 (1998) 67-87) (C) 199 8 Elsevier Science B.V.