Size-to-Charge Dispersion of Collision-Induced Dissociation Product Ions for Enhancement of Structural Information and Product Ion Identification

The role of some excited ions in laboratory ion–molecule reactions has been investigated, and their possible importance in the upper atmosphere considered. The mass spectrometer techniques of Aston banding and of comparing I.P. curves of parent and product ions have been applied to studies of collision-induced dissociation and charge exchange of oxygen and nitrogen in their parent gas. In every case studied, cross sections depended markedly upon the presence in the ion beam of ions in metastable or long-lived radiative states. In order that an ion reach the collision region, it had to have a mean lifetime greater than 3 μsec.The a 4Πu and b 4Σg excited states of O2+ were identified in the collision[Formula: see text]Higher states of O2+, which have not as yet been identified spectroscopically, were found in the collision[Formula: see text]The thresholds of these new states are 23.9, 27.9, 31.3, and 34.1 eV with an uncertainty ±0.2 eV. From the collision-induced dissociation of N2+, the A 2Πu and the [Formula: see text] states have been identified. Also, the reported transfer of the ν = 3 level of the B [Formula: see text] to the ν = 14 level of the A 2Πu was found.The cross section for 10/01 charged exchange of N2+ in N2 exhibited a marked decrease as excited-state ions diluted the beam. The 10/01 collisions of N+ in N2 and O+ in O2 exhibited an increase in cross section as metastables were added to the parent ion beam. The 10/20 reaction of O2+ in O2 was also observed to depend on excited O2+ ions.

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Competitive McLafferty-type rearrangements of sodium adduct of anti-2,3-dihydroxy-1-phenylpentane-1,4-dione compounds in tandem mass spectrometry

European Journal of Mass Spectrometry ◽

10.1177/1469066718803082 ◽

2018 ◽

Vol 24 (6) ◽

pp. 437-441 ◽

Cited By ~ 1

Author(s):

Xiayan Zhang ◽

Xu Xu ◽

Xinmeng Chen ◽

Lin Chen ◽

Xiaoying Xu ◽

...

Keyword(s):

Density Functional ◽

Mass Difference ◽

Fragmentation Pathway ◽

Density Functional Theory Calculations ◽

Sodium Cation ◽

Membered Ring ◽

Collision Induced Dissociation ◽

Sodium Adducts ◽

Main Fragmentation Pathway ◽

Product Ions

Sodium adducts of anti-2,3-dihydroxy-1-phenylpentane-1,4-dione compounds with different substituents were studied by collision-induced dissociation. McLafferty-type rearrangements preceding fragmentation were found as their main fragmentation pathway. Coordination of sodium cation to the oxygen functions may either lead to formation of a five-membered or a six-membered ring. Two McLafferty-type rearrangement product ions exhibiting a mass difference of 2 u indicated that two competitive McLafferty-type rearrangements through a six-membered ring coordination occurred. Relative abundances of the corresponding product ions were studied by energy-resolved collision-induced dissociation experiments and density functional theory calculations. Furthermore, the influence of different substituents was probed.

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An algorithm for interpretation of low-energy collision-induced dissociation product ion spectra forde novo sequencing of peptides

Rapid Communications in Mass Spectrometry ◽

10.1002/rcm.1892 ◽

2005 ◽

Vol 19 (8) ◽

pp. 1084-1096 ◽

Cited By ~ 7

Author(s):

Hongying Zhong ◽

Liang Li

Keyword(s):

Low Energy ◽

Collision Induced Dissociation ◽

Energy Collision ◽

Dissociation Product ◽

Product Ion Spectra

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Collision-Induced Dissociation of Peptide Thioesters: The Influence of Peptide Length on Fragmentation

European Journal of Mass Spectrometry ◽

10.1255/ejms.709 ◽

2005 ◽

Vol 11 (1) ◽

pp. 31-34 ◽

Cited By ~ 3

Author(s):

Corinne Buré ◽

Olivier Boujard ◽

Marylène Bertrand ◽

Catherine Lange ◽

Agnès F. Delmas

Keyword(s):

Mass Spectra ◽

Structural Information ◽

Neutral Loss ◽

Collision Induced Dissociation ◽

Quadrupole Mass ◽

Triple Quadrupole Mass Spectrometer ◽

Peptide Length ◽

Electrospray Source ◽

Peptide Thioesters ◽

Made In

Five peptide thioesters of increasing length were fragmented using two processes, in-source and in-collision cell fragmentation, using an electrospray source coupled to a triple quadrupole mass spectrometer. Comparison of their fragmentations was made in regard to their length. The two fragmentation conditions show that the peptide length has no influence on structural information and that the fragmentation efficiency is higher for the smallest peptides than for the longest. The particularity of these peptide thioesters consists of the neutral loss of ethanethiol. The absence of the a3 fragment ion and the presence of the (a3–17) ion on the collision-induced dissociation mass spectra are noted.

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