mechanisms of collisional activation of ions in mass spectrometry

• Published in: Mass spectrometry reviews 2009-07, Vol.28 (4), p.608-639
• Main Authors: Mayer, Paul M, Poon, Clement
• Format: Article
• Language: English
• Subjects: collision-induced dissociation; collisional energy transfer; curve-crossing excitation; Exact sciences and technology; impulsive collisions; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Mass spectrometers and related techniques; mechanisms of collisional excititation; Physics; slow-heating methods; surface-induced dissociation; tandem mass spectrometry
• ISSN: 0277-7037; 1098-2787
• DOI: 10.1002/mas.20225

This article is a review of the mechanisms responsible for collisional activation of ions in mass spectrometers. Part I gives a general introduction to the processes occurring when a projectile ion and neutral target collide. The theoretical background to the physical phenomena of curve-crossing excitation (for electronic and vibrational excitation), impulsive collisions (for direct translational to vibrational energy transfer), and the formation of long-lived collision intermediates is presented. Part II highlights the experimental and computational investigations that have been made into collisional activation for four experimental conditions: high (>100 eV) and intermediate (1-100 eV) center-of-mass collision energies, slow heating collisions (multiple low-energy collisions) and collisions with surfaces. The emphasis in this section is on the derived post-collision internal energy distributions that have been found to be typical for projectile ions undergoing collisions in these regimes.