(color online) (a) Plots of electron localization probabilities versus the amplitude of DC electric field for different localization ratios of the three protons, in which a DC electric field is utilized to steer the electron motions of the dissociation states after being excited by a UV laser pulse with a central frequency and intensity of 0.2 a.u. and W/cm², respectively. (b) Snapshot of the common logarithm of the electron-nuclear probability density distribution taken at the end of the dissociation, with the amplitude of the dc electric field being a.u.