We use a propagation step size of 0.002 fs (∼0.08268 a.u.). Trajectories with an applied sinusoidal external field have been generated by perturbing the molecules from their ground states. Trajectories with a delta-kick perturbation are generated by applying a constant electric field to the ground state self-consistent field calculation before beginning electron propagation. The TDHF trajectories have been generated using the GAUSSIAN program and the TDCIS trajectories have been generated using an in-house Python code that uses the GAUSSIAN generated CIS energies and transition dipoles as input parameters.