Communication: Rovibrationally selected study of the N2+(X; v+ = 1, N+ = 0−8) + Ar charge transfer reaction using the vacuum ultraviolet laser pulsed field ionization-photoion method

Abstract

Rovibrationally selected ion-molecule collision study using the molecular beam vacuum ultraviolet laser pulsed A vacuum-ultraviolet laser pulsed field ionization-photoelectron study of sulfur monoxide (SO) and its cation (SO +

Communication: Rovibrationally selected absolute total cross sections for the reaction H2O+(X2B1; v1+v2+v3+ = 000; N+Ka+Kc+) + D2: Observation of the rotational enhancement effect

“…The H 2 O beam thus formed traveled along the central axis of the DQDO apparatus, and intersected the VUV laser beam at the photoionization/photoexcitation (PI/PEX) region, resulting in the formation of prompt H 2 O + ions as well as excited H 2 O*(n ≈ 100) in high-n Rydberg states. By employing the pulsing scheme to the PI/PEX region as that described previously in detail, 15,16 we were able to generate a rovibrationally selected…”

“…15,16 Since the H 2 O + reactant ions react with D 2 in the reaction gas cell, the E cm value for the present cross section measurement depends not only on the E lab value for the reactant ion beam, but also the thermal motion of the D 2 gas in the gas cell at the temperature T = 298 K. Chantry has shown that the E cm value or the Doppler width caused by the thermal motion of the target gas alone is W 1/2 = (11.1γ kTE cm ) 1 Figs. 1(a) and 1(b), respectively.…”

“…We have recently implemented a high-resolution VUV laser PFI-PI ion source with a double-quadrupoledouble-octopole (DQDO) ion guide apparatus for absolute total cross section measurements of state-selected ion-molecule reactions. 15,16 The application of a novel electric-field pulsing scheme for the VUV laser PFI-PI ion source has made possible the preparation of a rovibrationally selected reactant PFI-PI N 2 + (X 2 g + ; v + = 0-2, N + = 0-9) ion beam with not only single quantum state purity, but also high laboratory kinetic energy (E lab ) resolution. The absolute total cross section for the N 2 + (X 2 g + ; v + = 0-2) + Ar charge transfer reaction is found to be independent of rotational excitation in the range of N + = 0-9.…”

“…the investigation of kinetic, 9 vibrational, and electronic energy effects of reactant ions. [2][3][4][5][6][7][8] Up to the present, five stateselected ion-molecule reaction studies 1,[10][11][12][13][14][15][16] have been reported aiming to examine the reactivity of ions in different rotational levels. All of these studies were concerned with the rotational selection of diatomic reactant ions, H 2 + , NO + , CO + , HBr + , and N 2 + , prepared by the autoionization, resonance-enhanced multi-photon ionization, or pulsed field ionization-photoion 17 (PFI-PI) methods.…”

“…15 The experimental arrangement and procedures for using the VUV laser PFI-PI DQDO ion guide apparatus for absolute total cross section measurements of ion-molecule collisions involving rovibronically selected reactant ions have been described in detail. 15,16 The coherent VUV radiation used was generated by resonance-enhanced four-wave sumfrequency mixing using a Xe jet as the nonlinear medium. 21,22 The H 2 O molecular beam was produced by supersonic expansion of a H 2 O/He mixture (mixing ratio H 2 O:He = 1:99) at a total stagnation pressure of ≈1500 Torr through a pulsed valve with a nozzle diameter of 0.5 mm.…”