Crossed beam study of the reaction of H+3 with D2

Fundamentals of tandem mass spectrometry: a dynamics study of simple C−C bond cleavage in collision-activated dissociation of polyatomic ions at low energy

“…The earlier molecular beam study of the dynamics of methane and propane ion CAD used the QET of mass spectra to interpret the dynamics, The conver-_ sion of translational to internal energy (at a given collision energy) was shown to correlate approximately linearly with scattering angle. Different scattering angles for individual CAD channels result from the different energy requirements for competing dissociation processes, as shown most clearly by the QET breakdown graph for the propane molecular ion [11). A distribution of vibrationally excited ground-state molecular ions are excited by collision to a broad distribution of excited vibronic states of the propane ion.…”

“…Despite these many similarities, the detailed kinetics of the unimolecular decay of excited acetone and propane ions are markedly different. The propane ion has served for many years as an archetypical example of ions whose dissociation processes are welldescribed by the QET of mass spectra [11,12]. For acetone, on the other hand, it has been demonstrated in careful studies by Lifshitz et al [13,14], and by others [15][16][17][18] that the metastable decay and CAD of the acetone ion are bimodal and cannot be explained by the QET, that is, it is an archetypical example of a non-QET molecular ion.…”

Simulations of ion velocity distribution functions taking into account both elastic and charge exchange collisions

“…Angular differential cross sections. Experimental data are shown by the blue curve [18]. The red curve shows the approximation proposed in this paper, Eq.…”

“…However, scattering in the ion-atom collisions can be significant [14][15][16]. Therefore, ion-atom angular differential scattering cross sections [17][18][19][20] have to be taken into account for accurate calculations of IVDF.…”

An Autobiography

“…6 By this time we were totally confident we could drastically modify or create mass analyzers for any purpose and we constructed a crossed beam ion gun supersonic neutral jet apparatus for investigating the dynamics of ion reactions. 7 Shortly thereafter we built the first tandem quadrupole spectrometer. 8 It was an exciting time to work in this field.…”