Reliability of Fourier transform-ion cyclotron resonance determinations of rate constants for ion/molecule reactions

1996 ◽  
Vol 2 (1) ◽  
pp. 213 ◽  
Author(s):  
Renaud Grover ◽  
Michèle Decouzon ◽  
Pierre- Charles Maria ◽  
Jean- François Gal
Keyword(s):  
Fourier Transform ◽  
Rate Constants ◽  
Cyclotron Resonance ◽  
Ion Cyclotron Resonance ◽  
Ion Molecule Reactions ◽  
Ion Cyclotron

Mechanism and Structure in the Ion Chemistry of Tetramethyldiphosphine: An Ion Cyclotron Resonance Spectrometric Study

1976 ◽  
Vol 31 (5) ◽  
pp. 414-421 ◽  
Author(s):  
Karl-Peter Wanczek
Keyword(s):  
Mass Spectrum ◽  
Rate Constants ◽  
Cyclotron Resonance ◽  
Double Resonance ◽  
Ion Cyclotron Resonance ◽  
Spectrometric Study ◽  
Ion Chemistry ◽  
Ion Molecule Reactions ◽  
Ion Cyclotron ◽  
Ion Cyclotron Resonance Spectrometry

Abstract The mass spectrum of tetramethyldiphosphine and the ion chemistries of this compound and of its mixtures with phosphine and dimethylphosphine have been investigated by ion cyclotron resonance spectrometry. Numerous ion molecule reactions have been observed. The rate constants of the two most abundant ions formed by the molecular ion, the tetramethyldiphosphonium ion, H(CH3)2P-P(CH3)2+ and the hexamethyltriphosphonium ion, P3(CH3)6+ , are k2.35≦0.1X10-10 cm3 molecule-1 s-1 and k2.40 = 1.5 X10-10 cm3 molecule -1 s -1 respectively. The structures of several ions have been determined with the aid of their ion-molecule reactions. The ions m/e = 79 and 93 are thought to have the structures HP - P(CH3)H+ and HP-P(CH3)2+ . The most probable structures of the ions m/e = 169 and 183 are HP(CH3)2-P(CH3)-P(CH3)2+ and (CH3)2P-P(CH3) - P(CH3)3+ . The protonated molecule undergoes several ion-molecule reactions, which proceed via an intermediate, m/e = 183, [(CH3)6P3+]* which is detected by double resonance experiments.

Mass Spectra and Ion Chemistry of Methylphosphine, Dimethylphosphine and Dimethyldeuterophosphine, Investigated by Ion Cyclotron Resonance Spectrometry

1975 ◽  
Vol 30 (3) ◽  
pp. 329-339 ◽  
Author(s):  
Karl-Peter Wanczek
Keyword(s):  
Rate Constants ◽  
Cyclotron Resonance ◽  
Mass Spectra ◽  
Ion Cyclotron Resonance ◽  
Exchange Reactions ◽  
Ion Chemistry ◽  
Ion Molecule Reactions ◽  
Ion Cyclotron ◽  
Product Ions ◽  
Ion Cyclotron Resonance Spectrometry

The mass spectra and the ion molecule reactions of methylphosphine, dimethylphosphine and dimethyldeuterophosphine have been studied by ion cyclotron resonance spectrometry. About 50 ion molecule reaction are observed for each compound. The product ions can be classified as ions with two phosphorus atoms: P2R5+, P2R3+, P2R2+ and P2R+ (R = CH3 or H), as phosphonium and phosphinium ions and ions resulting from collision dissociations and charge exchange reactions. Tertiary ions with three phosphorus atoms like CH3P3H2+ (from CH3PH2) and (CH3)4P3H2 (from (CH3)2PH) have also been detected. The mechanisms of the ion molecule reactions, rearrangements, P -H- and C-H-reactivities and product ion structures are discussed, using in the case of dimethylphosphine the results obtained with the deuterated compound. Rate constants of formation of the more abundant product ions from the molecular ion and the CH3P+ ion, both odd electron particles, have been determined. The reactions with dimethylphosphine have much smaller rate constants than the reactions with methylphosphine.

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