Charge transfer dissociative

Dissociative charge transfer. Occurs when an ion/molecule reaction takes place in which the charge on the ion is transferred to the neutral species. The new ion then dissociates to one or more fragment ions. 

A sample of 14N15NO was used to investigate whether Reaction 14 proceeds through a dissociative charge transfer mechanism involving an... 

The problems of distinguishing H+ produced from H2 by electron impact from the product of dissociative charge transfer reactions between He + and H2 can be studied by determining the kinetic energy distribution in the product H+ (6). The reaction He+ + H2 is exothermic by 6.5 e.v. if the products are atoms or atomic ions. If the reaction is studied with HD substituted for H2, then the maximum kinetic energy that can be deposited in the D + is approximately 2.16 e.v. On the other hand, D + can be produced by electron impact with 5.5 e.v. kinetic energy. If a retarding potential is applied at the repeller in the ion-source of a mass spectrometer, then it is possible to obtain curves related to the kinetic... 

Dissociative Charge Transfer. Knewstubb and Sugden (27) have observed mass spectrometrically that NO+ ions are formed when 1% of NO is supplied to the unburned gases of an atmospheric-pressure H2/02/N2 flame at 2300°K. These authors originally suggested that their results could be accounted for in terms of the dissociative charge transfer... 

Mass spectrometric studies of the ionic species which arrive at the cathode of both glow and corona discharges yield useful information regarding ion-molecule reactions which occur within these systems. Glow discharges have been used to study endothermic reactions, and their usefulness and limitations have been demonstrated by studies of the dissociative charge transfer reactions Ar+ + N2 N+ + N + Ar N2+ + N2 N+ + N + N2 N2+ + 02 0+ + O + N2. Exo-... 

The corrected data thus obtained could be used to evaluate the variation of the cross-section of the dissociative charge-transfer reaction with ion energy. 

The nomenclature used here and throughout the tables presented in this review to designate ion-neutral reactions conforms to that currently in use (see Ref. Id, p. 104). For collisional dissociation and dissociative charge transfer, we have adopted the notations AB (X X B)A and A+(BC A,B)C, respectively. 

Many dissociative charge-transfer reactions6 that are endoergic for ground-state ions also become energetically allowed for some electronically excited state of the reactant ion. For example, the reaction of excited Kr + ions with methane has been observed18,19... 

Charge-transfer and dissociative-charge-transfer reactions of diatomic ions with various molecules that yield luminescence spectra are summarized in Table IV.B, part 3. In some of these, for example, the H2+ —N2 reaction, vibrational and rotational excitation have again been observed to accompany electronic excitation.155, 426 Molecular-ion reactions are generally accompanied by more extensive rotational excitation of the products than occurs with atomic-ion reactions.439... 

The effect of reactant internal vibrational energy on molecular fragment ion ratios resulting from dissociative charge transfer of some large alkanes has also been accurately predicted by the QET.476... 

SiH3+ ions are easily formed in the reactions of noble gas cations and other small ions with SiFLt via dissociative charge transfer (equation l)11. 

Nonsymmetric charge transfer Symmetric (resonance) charge transfer Dissociative charge transfer Associative ionization Photoionization Cumulative ionization... 

Rutherford and Vroom studied A1+ collisions with O2 and N2 at ion energies ranging from 1 to 5000 eV in a crossed beam apparatus involving a modulated neutral beam. ° The aluminum ions were produced by surface ionization of AICI3 vapor on a hot tungsten filament and product ions were detected mass spectrometrically. In the AI+ + O2 collision system, the 02" " formation cross section was found to be at the detection limit of 0.01 A at 1 keV ion energy ( 115 km/s), after which it rose to values above 0.1 A at 5 keV. N2" formation in A1+ -f N2 collisions was only measurable above 1.5 keV ( 150 km/s). The dissociative charge transfer processes ... 

VOCs mostly react with 02+ via charge transfer (Equation (21)) or dissociative charge transfer (Equation (22)) however, this reagent ion has found most use in monitoring NO, N02, and CS2 as NO+, N02 +, and CS2 + , respectively. 

Ar" " and Nj have similar recombination energies and for some reactions have similar reactivity even though one is atomic and the other diatomic. The similarities and differences in the reactions of these two ions with O2 was described above. The reactions of these ions with CO2 and SO2 have also been studied in the HTFA. " The reactions with CO2 proceed exclusively by charge transfer and the SO2 reaction is mainly charge transfer except at high temperature/energy where SO" " is produced by dissociative charge transfer, a process which is endothermic at room temperature. 

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