Fig. 4.

Quantum dynamical wave packet calculations. (A and B) The stretching (Top) of C-S internuclear distance, R_CS, and bending (Bottom) of the S-C-S bond angle, ϕ_SCS, for (A) neutral CS₂ in the ${\stackrel{\sim }{\text{B}}}^1{\text{B}}_2$ state and (B) CS₂⁺ cation. The starting conditions used are (A) neutral CS₂ in the ${\stackrel{\sim }{\text{X}}}^1{\Sigma }_{\text{g}}^{+}$ ground electronic state (1.55 Å, 180°) and (B) neutral CS₂ in the ${\stackrel{\sim }{\text{B}}}^1{\text{B}}_2$ excited electronic state (1.7 Å, 117°). The blue rectangle indicates the initial bending of neutral CS₂. The red (green) oval indicates the relevant structure at around the time of ionization (rescattering), t_i (t_r). Here, molecules are 90° to the laser polarization. In A, t = 0 fs corresponds to the peak of the 85-fs (FWHM) 3.1-μm pulse envelope, while in B the time axis corresponds to the time after ionization. The corresponding laser field is shown as white traces in A and B, Top.