Extended Data Fig. 5: Late-time charge evolution.
From: X-ray multiphoton-induced Coulomb explosion images complex single molecules
Late-time charge evolution for 2-iodopyridine for (A) I+ + N+ coincidences (continuation of Fig. 2D), and (B) I4+ + N2+ coincidences (continuation of Extended Data Fig. 3B). The error bars in (B) correspond to the standard error of the mean, in (A), those errors are smaller than the data point markers. The final charge states, in particular of iodine, are only reached at the end of the propagation time, after about 1 ps, which can be understood as follows: photo- and Auger electrons are treated as classical particles in XMDYN. If they are captured in the attractive potential created by all charged ions, they are no longer considered free particles, but delocalized electrons. If their kinetic energy is lower than the electrostatic attraction towards a given ion, they are trapped in its field and the ion’s charge is correspondingly reduced by − 1. The decrease/increase in (A)/(B) is caused by an increase/decrease in the average number of electrons trapped around iodine. A possible reason for the increase of the iodine charge in (B) is autoionization-like events between two trapped electrons, or between a delocalized electron and a trapped one, where one trapped electron receives enough energy to leave the field around the ion.
