Fig. 1. (A) Two typical pathways after electron attachment to XYZ and Morse potential curves of XYZ and XYZ^- (left) and (B) differential cross sections of $\sigma_{\rm{EA}}$ and $\sigma_{\rm{DEA}}$ (right).

Fig. 2. (A) O^- and (B) C^- production efficiency curves of the DEA to CO₂ (reproduced from [32, 34]).

Fig. 3. Schematics of our (A) low- and (B) high- resolution VMI apparatuses.

Fig. 4. High-resolution O^- velocity images of the DEAs to CO₂ at the electron energies of (A) 4.15, (B) 4.55, and (C) 4.95 eV. The electron incident direction (along y axis) is from top (backward) to bottom (forward) and through the image center.

Fig. 5. Assignments with the rotational states $j$=0-25 of CO ($X^1\Sigma^+$, $v$=0) of the O^- kinetic energy distributions in the forward (A, $\theta$ from -15° to 15°) and backward (B, $\theta$ from -165° to 165°) scattering directions. The solid circles are the relative intensities of O^- ions observed in FIG. 4(A), the vertical lines show the intensities of different rotational states, and the red curves show the fitting profiles of all rotational states considered here. In the data fittings, a gaussian function with an energy width of 0.03 eV is used for each rotational state.

Fig. 6. Angular distributions of O^- ions produced in the DEA to CO₂ at 4.15 eV. The co-product CO ($X^1\Sigma^+$, $v$=0) is populated at different rotational states ($j$).

Fig. 7. Renner-Teller split states coupling with the dissociation pathway in Franck-Condon region of electron attachment (A). Time-sliced O^- velocity images of the DEA to CO₂ are recorded at electron energies of 7.7 eV (B), 8.2 eV (C), and \mbox{8.7 eV} (D) \cite{28}. The electron incident direction (along $x$ aix) is from left (backward) to right (forward) and through the image center.

Fig. 8. High-resolution O^- image (A) and the O^- kinetic energy distribution (B) for the DEA to CO₂ at the electron energy of 13 eV. In (A), the electron incident direction (along the $y$ axis) is from top (backward) to bottom (forward) and through the image center.

Fig. 9. Three-dimensional image of C^- of the DEA to CO₂ at the electron energy of 15.9 eV. The red circle is the demarcation of three-body dissociation and two-body dissociation.

Fig. 10. (A) Daytime photoelectrons spectrum in the Earth ionosphere (reproduced from [84]), in which each line represents a different height. (B) Energy spectra of oversampled photoelectrons in the Martian ionosphere, where the electron flows toward and away from Mars are marked in red and green respectively (reproduced from [85]). The vertical bars shaded in blue correspond to the electron energy range investigated in the DEA study [27].

Fig. 11. (A) Energetics comparison between the neutral dissociation and DEA processes of CO₂. (B) Surface catalytic processes of CO₂.