Fragmentation processes internal

Similarities between mass spectral and thermal fragmentations are particularly common in certain reaction types. Electrocyclic reactions, for example, are frequently similar in the two processes. The thermal process has in general a higher stereoselectivity (because of the higher aromaticity in even-electron systems). Retro-Diels-Alder reactions are typical examples for the similarity of the two processes. Internal displacement reactions may also be similar in the two processes, mainly in the case of internal radical displacements. The relationship between mass spectra and thermal fragmentation is complex, and it is useful to discuss it for separate classes of compounds. 

Then, Qx allows to select the ion of interest. If a collision gas is injected into Q2, (operating in rf only, i.e., with only yrf and with U = 0), M+ will collide with the target gas molecules. Its internal energy will increase, promoting the occurrence of the fragmentation processes. 

Huppertz and Smiddy (2008) demonstrated that application of high pressure (250-300 MPa) led to an initial rapid micellar disruption this was followed by a partial reversal of the high-pressure-induced reassociation of micellar fragments. Partial internal cross-linking of casein micelles by transglutaminase prior to pressure treatment considerably slowed down both the disruption and reassociation processes. 

Hsu F.F., Turk J., Studies on sulfatides by quadrupole ion-trap mass spectrometry with electrospray ionization structural characterization and the fragmentation processes that include an unusual internal galactose residue loss and the classical charge-remote fragmentation, Journal of the American Society for Mass Spectrometry 15 (2004) 536-546. 

Gas phase clusters undergo fragmentation when their internal temperature is high enough. The theoretical study of such fragmentation processes, M - ... 

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