Tandem flowing afterglow-selected ion flow tube and its application to the thermal energy reactions of 18O-

1987 ◽  
Vol 109 (14) ◽  
pp. 4412-4414 ◽  
Author(s):  
Jane M. Van Doren ◽  
Stephan E. Barlow ◽  
Charles H. DePuy ◽  
Veronica M. Bierbaum
Keyword(s):  
Thermal Energy ◽  
Flow Tube ◽  
Flowing Afterglow ◽  
Ion Flow ◽  
Selected Ion Flow Tube

A flowing afterglow selected ion flow tube (FA/SIFT) comparison of SIFT injector flanges and H3+ + N revisited

2000 ◽  
Vol 202 (1-3) ◽  
pp. 351-361 ◽  
Author(s):  
Daniel B Milligan ◽  
David A Fairley ◽  
Colin G Freeman ◽  
Murray J McEwan
Keyword(s):  
Flow Tube ◽  
Flowing Afterglow ◽  
Ion Flow ◽  
Selected Ion Flow Tube

ChemInform Abstract: Reaction of Anions with Activated Olefins in the Gas Phase. A Flowing Afterglow-Selected Ion Flow Tube Study.

ChemInform ◽  
2010 ◽  
Vol 22 (12) ◽  
pp. no-no
Author(s):  
C. F. BERNASCONI ◽  
M. W. STRONACH ◽  
C. H. DEPUY ◽  
S. GRONERT
Keyword(s):  
Gas Phase ◽  
Flow Tube ◽  
Flowing Afterglow ◽  
Ion Flow ◽  
Selected Ion Flow Tube ◽  
Activated Olefins ◽  
Tube Study

scholarly journals Anions in Space and in the Laboratory

2011 ◽  
Vol 7 (S280) ◽  
pp. 383-389 ◽  
Author(s):  
Veronica M. Bierbaum
Keyword(s):  
Reaction Pathway ◽  
Hydrogen Atoms ◽  
Flow Tube ◽  
Flowing Afterglow ◽  
Ion Flow ◽  
Reaction Rate Constants ◽  
Molecular Anions ◽  
Selected Ion Flow Tube ◽  
Reaction Barriers

AbstractThe astronomical detection of molecular anions has prompted our study of their chemical reactions with atomic species that are abundant in the interstellar medium. We have recently explored the chemistry of a variety of Cx Ny− anions with hydrogen atoms and determined their reaction rate constants and products using the flowing afterglow-selected ion flow tube technique. Computational studies allow characterization of the structures of reactants and products, as well as the energetics along the reaction pathway. For anions containing one or two nitrogen atoms, reactions with hydrogen atoms are facile, and proceed primarily by associative detachment. In contrast, anions containing three nitrogen atoms are unreactive with hydrogen atoms due to reaction barriers and unfavorable thermodynamics.

Fragmentations of Deprotonated Alkyl Hydroperoxides (ROO− Upon Collisional Activation: A Combined Experimental and Computational Study

2003 ◽  
Vol 56 (5) ◽  
pp. 459 ◽  
Author(s):  
Stephen J. Blanksby ◽  
Shuji Kato ◽  
Veronica Bierbaum ◽  
G. Barney Ellison
Keyword(s):  
Mass Spectra ◽  
Computational Study ◽  
Flow Tube ◽  
Flowing Afterglow ◽  
Ion Flow ◽  
Alkyl Hydroperoxides ◽  
Ionic Fragment ◽  
Selected Ion Flow Tube ◽  
Subsequent Decomposition ◽  
Structure Calculations

The collision-induced dissociation (CID) mass spectra of the [M − H]– anions of methyl, ethyl, and tert-butyl hydroperoxides have been measured over a range of collision energies in a flowing afterglow–selected ion flow tube (FA-SIFT) mass spectrometer. Activation of the CH3OO– anion is found to give predominantly HO– fragment anions whilst CH3CH2OO− and (CH3)3COO– produce HOO– as the major ionic fragment. These results, and other minor fragmentation pathways, can be rationalized in terms of unimolecular rearrangement of the activated anions with subsequent decomposition. The rearrangement reactions occur via initial abstraction of a proton from the α-carbon in the case of CH3OO– or the β-carbon for CH3CH2OO– and (CH3)3COO–. Electronic structure calculations suggest that for the CH3CH2OO– anion, which can theoretically undergo both α- and β-proton abstraction, the latter pathway, resulting in HOO– + CH2CH2, is energetically preferred.

Reactions of Ar+with Selected Volatile Organic Compounds. A Flowing Afterglow and Selected Ion Flow Tube Study

2000 ◽  
Vol 104 (48) ◽  
pp. 11318-11327 ◽  
Author(s):  
Michael H. Cohen ◽  
Cynthia Barckholtz ◽  
Brian T. Frink ◽  
Joshua J. Bond ◽  
C. Michael Geise ◽  
...  
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Flow Tube ◽  
Flowing Afterglow ◽  
Ion Flow ◽  
Volatile Organic ◽  
Selected Ion Flow Tube ◽  
Tube Study

Acid catalysis in the gas phase: dissociative proton transfer to formate and acetate esters

1979 ◽  
Vol 57 (22) ◽  
pp. 2996-3004 ◽  
Author(s):  
A. C. Hopkinson ◽  
G. I. Mackay ◽  
D. K. Bohme
Keyword(s):  
Proton Transfer ◽  
Gas Phase ◽  
Major Product ◽  
Flow Tube ◽  
Flowing Afterglow ◽  
Phase Measurements ◽  
Ion Flow ◽  
Intrinsic Kinetics ◽  
Selected Ion Flow Tube ◽  
Kinetics Of

The flowing afterglow and selected ion flow tube techniques are employed in gas-phase measurements of the intrinsic kinetics of protonation of methyl formate, n-propyl formate, ethyl acetate, and n-propyl acetate and subsequent fragmentation according to[Formula: see text]with R = H and CH3, R′ = CH3, C2H5, and (CH2)2CH3, and A = H2, CH4, CO, and H2O. Protonation by the acids, AH+, with relative strengths spanning a range of 65 kcal mol−1, is observed to proceed extremely rapidly with rate constants at 299 ± 2 K encompassing values of 2.9 to 8.5 × 10−9 cm3 molecule−1 s−1. Fragmentation is observed for HCOOCH3 only with the strongest acid, H3+, to produce CH3OH2+. For HCOO(CH2)2CH3, fragmentation is observed to produce C3H7+ with H3O+, and also HCOOH2+ with H3+. Little fragmentation of CH3COOC2H5 occurs with H3O+ but with H3+ the major product is CH3COOH2+ with smaller amounts of CH3CO+ and C2H5+. Proton transfer from H3O+ to CH3COO(CH2)2CH3 results in considerable dissociation to form CH3COOH2+. The fragmentation of these esters is discussed in terms of known reaction energetics and in terms of mechanisms for unimolecular acyl–oxygen, AAc1, and alkyl–oxygen, AA11, fission often invoked for analogous reactions in solution as well as modifications of these mechanisms which have been proposed in the context of recent gas-phase measurements.

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