Author: C. H. Watson
Publisher:
ISBN:
Category :
Languages : en
Pages : 28
Book Description
Collision induced dissociation and infrared multiphoton dissociation of ions formed in di- and triethylamine, di- and tri-n-propylamine, and diisopropylamine were investigated by Fourier transform ion cyclotron resonance mass spectrometry. Molecular ions of all amines except di-n-propylamine produced similar fragment ions when subjected to either dissociation technique. The initial fragmentation involved C(alpha)-C(beta) bond cleavage, loss of an alkyl radical, and formation of an immonium ion. Subsequent fragmentations of the immonium ions produced by both dissociation mechanisms involved McLafferty type rearrangements and loss of alkenes. The molecular ion of di-n-propylamine fragmented by a different mechanism when subjected to infrared irradiation. Protonated molecules of di- and tri-n-propylamine yielded C3H6 and an ammonium ion upon infrared multiphoton dissociation, while protonated molecules of the other amines did not dissociate using this technique. Collision induced dissociation, on the other hand, produced fragmentation for all protonated molecules. Explanation of the different fragmentations observed for the two dissociation techniques is given in terms of a mechanism involving a tight transition state for protonated di- and tri-n-propylamine dissociation. Keywords: Infrared Multiphoton Dissociation; Collision Induced Dissociation; Alkylamines; Fourier Transform Ion Cyclotron Resonance Mass Spectrometry.
Infrared Multiphoton and Collision Induced Dissociation Studies of Some Gaseous Alkylamine Ions
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages :
Book Description
Infrared Multiphoton Dissociation of Gaseous Ions Studied by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry
Author: Clifford Hunter Watson
Publisher:
ISBN:
Category : Ion cyclotron resonance spectrometry
Languages : en
Pages : 304
Book Description
Publisher:
ISBN:
Category : Ion cyclotron resonance spectrometry
Languages : en
Pages : 304
Book Description
Government Reports Announcements & Index
Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 1278
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 1278
Book Description
Government Reports Annual Index
Author:
Publisher:
ISBN:
Category : Government reports announcements & index
Languages : en
Pages : 900
Book Description
Publisher:
ISBN:
Category : Government reports announcements & index
Languages : en
Pages : 900
Book Description
Molecular Beam Studies of Infrared Multiphoton Dissociation and Inelastic Gas-surface Scattering
Author: Cindy Linea Berrie
Publisher:
ISBN:
Category :
Languages : en
Pages : 210
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 210
Book Description
Infrared Multiphoton Dissociation of Gaseous Ions in a Quadrupole Ion Storage Trap
Author: Alexander Baldwin Young
Publisher:
ISBN:
Category : Water
Languages : en
Pages : 226
Book Description
Publisher:
ISBN:
Category : Water
Languages : en
Pages : 226
Book Description
Angle and Energy Resolved Studies of the Collision Induced Dissociation of Polyatomic Molecular Ions
Author: Stephen Gee Anderson
Publisher:
ISBN:
Category : Collision spectroscopy
Languages : en
Pages : 636
Book Description
Publisher:
ISBN:
Category : Collision spectroscopy
Languages : en
Pages : 636
Book Description
Energy-resolved Collision-induced Dissociation Studies for Ion Thermochemistry
Author: Alex Andrew Nickel
Publisher:
ISBN:
Category : Electronic books
Languages : en
Pages : 398
Book Description
Energy-resolved competitive threshold collision-induced dissociation (TCID) measurements for radical species relevant to combustion were made using a guided ion beam tandem mass spectrometer. These ion thermochemistry methods can be used to obtain thermochemical properties of these neutral radicals through the use of thermochemical cycles. The high reactivity of radical species often makes them challenging to directly measure. Study of the peroxyformate anion (HC(O)OO−) revealed a singlet-triplet crossing in the oxygen-oxygen bond dissociation channel. Analysis of the thresholds gives the first experimentally determined enthalpies of formation for both peroxyformic acid and the peroxyformyl radical. We have also studied the TCID of linear and branched hexanol (C6H13OH) complexed with fluoride and acetylide to determine their gas-phase acidities. The role of conformation on the gas-phase acidities of 1-hexanol and 3, 3-dimethyl-1-butanol was explored using modified microcanonical statistical rate theory (RRKM) models with internal rotations treated as one-dimensional hindered rotors. These six-carbon primary alcohols have the same “intrinsic” gas-phase acidity, defined as deprotonation without conformational relaxation, but differ in observed acidity due to conformational stabilization of the anion.
Publisher:
ISBN:
Category : Electronic books
Languages : en
Pages : 398
Book Description
Energy-resolved competitive threshold collision-induced dissociation (TCID) measurements for radical species relevant to combustion were made using a guided ion beam tandem mass spectrometer. These ion thermochemistry methods can be used to obtain thermochemical properties of these neutral radicals through the use of thermochemical cycles. The high reactivity of radical species often makes them challenging to directly measure. Study of the peroxyformate anion (HC(O)OO−) revealed a singlet-triplet crossing in the oxygen-oxygen bond dissociation channel. Analysis of the thresholds gives the first experimentally determined enthalpies of formation for both peroxyformic acid and the peroxyformyl radical. We have also studied the TCID of linear and branched hexanol (C6H13OH) complexed with fluoride and acetylide to determine their gas-phase acidities. The role of conformation on the gas-phase acidities of 1-hexanol and 3, 3-dimethyl-1-butanol was explored using modified microcanonical statistical rate theory (RRKM) models with internal rotations treated as one-dimensional hindered rotors. These six-carbon primary alcohols have the same “intrinsic” gas-phase acidity, defined as deprotonation without conformational relaxation, but differ in observed acidity due to conformational stabilization of the anion.
American Chemical Society Directory of Graduate Research, 1987
Author: American Chemical Society, Committee on Professional Training Staff
Publisher:
ISBN: 9780841214187
Category : Science
Languages : en
Pages : 1390
Book Description
Publisher:
ISBN: 9780841214187
Category : Science
Languages : en
Pages : 1390
Book Description