Dissociation Dynamics of Anionic Carbon Dioxide in the Shape Resonant State ²Π_u

Abstract

Dissociative electron attachments via the lowest shape resonant state 2 Π u of CO 2 − , e − + CO 2 → O − + CO, are investigated with our high-resolution anion velocity map imaging apparatus. The production efficiency curve of O − obtained in this work is consistent with those reported previously. The forward− backward asymmetric distribution superimposed on the isotopic background is observed in the time-sliced velocity image of O − yield, implying that the dissociation of CO 2 − ( 2 Π u ) proceeds through a combinational motion of bond stretching and bending. Thereby, the coproduct CO is proposed to be in the rovibrational states. The long-standing arguments about the dissociation dynamics of CO 2 − ( 2 Π u ) are settled.

Electron and Positron Scattering Cross Sections from CO2: A Comparative Study over a Broad Energy Range (0.1–5000 eV)

“…− anion. These features were confirmed later by Cicman al., 63 and more recently by Fan et al, 64 assigning the main structures to the vibrational states of CO over much weaker and narrower structures due to the transient CO 2…”

“…They attributed this structure to the final vibrational states of the formed CO molecule together with the vibrational structure of the intermediate CO 2 – anion. These features were confirmed later by Cicman al., and more recently by Fan et al, assigning the main structures to the vibrational states of CO over much weaker and narrower structures due to the transient CO 2 – anion. Above this π u shape resonance, some structures can be distinguished in the present data which are not visible in the Itikawa’s recommended TCS values.…”

Dissociation Dynamics of Anionic Nitrogen Dioxide in the Low-Lying Resonant States

“…The operation frequency is 50 kHz, and a off-line data analyses. 13 In our experiments, the commercial NO 2 gas sample (with a purity of 99.999%) was introduced into the chamber with an inlet nozzle, and the ambient pressure in the reaction chamber was controlled at ∼1.0 × 10 −6 mbar during the measurements.…”

“…In the DEA dynamics studies, we initiated the high-resolution VMI project a few years ago − and recently achieved near-threshold VMI measurements . The energy spread (100–150 meV) of the monochromatized electrons for the high-resolution VMI measurements is much smaller than that (500–600 meV) of the thermal electrons emitted directly from the filament, and it is not worsened seriously under the electron-pulsed mode . Using the high-resolution VMI apparatus, − here we report an experimental study of the near-threshold DEA process of nitrogen dioxide [e – + NO 2 (X 2 A 1 ) → NO 2 – → NO (X 2 Π) + O – ( 2 P)].…”

“…In contrast to the conventional turntable ion detection (e.g., see ref ), VMI has exhibited merit in detecting the charged yields; , more noticeably, a very high resolution was achieved with the slow photoelectron VMI technique . In the DEA dynamics studies, we initiated the high-resolution VMI project a few years ago − and recently achieved near-threshold VMI measurements . The energy spread (100–150 meV) of the monochromatized electrons for the high-resolution VMI measurements is much smaller than that (500–600 meV) of the thermal electrons emitted directly from the filament, and it is not worsened seriously under the electron-pulsed mode .…”