Negative ion-atmospheric pressure photoionization: Electron capture, dissociative electron capture, proton transfer, and anion attachment
نویسندگان
چکیده
منابع مشابه
Electron capture atmospheric pressure photoionization mass spectrometry: analysis of fullerenes, perfluorinated compounds, and pentafluorobenzyl derivatives.
An electron capture (EC) ionization mechanism has been found to be highly efficient in negative-ion atmospheric pressure photoionization (APPI) for the analysis of compounds with positive electron affinity (EA). Using negative-ion APPI, we first report the sensitive detection of natural electrophores with limited polarity, such as fullerenes and perfluorinated compounds, by mass spectrometry (M...
متن کاملElectron attachment step in electron capture dissociation (ECD) and electron transfer dissociation (ETD).
We have made use of classical dynamics trajectory simultions and ab initio electronic structure calculations to estimate the cross sections with which electrons are attached (in electron capture dissociation (ECD)) or transferred (in electron transfer dissociation (ETD)) to a model system that contained both an S-S bond that is cleaved and a -NH(3)(+) positively charged site. We used a Landau-Z...
متن کاملDistance dependence of through-bond electron transfer rates in electron-capture and electron-transfer dissociation
Ab initio electronic structure calculations on model cations containing a disulfide linkage and a protonated amine site are carried out to examine ow the rate of electron transfer from a Rydberg orbital on the amine site to the S S * orbital depends upon the distance between these two rbitals. These simulations are relevant to both electron-capture and electron-transfer dissociation mass spectr...
متن کاملDissociative electron attachment to DNA.
Electron-stimulated desorption of anions from thin films of linear and supercoiled DNA is investigated in the range 3-20 eV. Resonant structures are observed with maxima at 9.4+/-0.3, 9.2+/-0.3, and 9.2+/-0.3 eV, respectively, in the yield dependence of H-, O-, and OH- on the incident electron energy. Their formation is attributed to dissociative electron attachment.
متن کاملAnion Dependence in the Partitioning between Proton and Electron Transfer in Ion/Ion Reactions
Gas-phase reactions of singly-charged anions with multiply-protonated peptides, in a RF quadrupole linear ion trap, leads to either peptide deprotonation (proton transfer) or electron deposition (electron transfer). The former process induces peptide backbone cleavage through a reaction scheme analogous to electron capture dissociation (ECD). Here we characterize the preferred reaction pathways...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of the American Society for Mass Spectrometry
سال: 2007
ISSN: 1044-0305,1879-1123
DOI: 10.1016/j.jasms.2007.07.015