Tracking the nuclear movement of the carbonyl sulfide cation after strong-field ionization by time-resolved Coulomb-explosion imaging
Xinning Zhao, Ting Xu, Xitao Yu, Dianxiang Ren, Xinyu Zhang, Xiaokai Li, Pan Ma, Chuncheng Wang, Dongdong Zhang, Qinxin Wang, Xiaoqing Hu, Sizuo Luo, Yong Wu, Jianguo Wang, Dajun Ding
Abstract
We studied the ultrafast nuclear dynamics during the dissociation of ${\mathrm{OCS}}^{+}$ molecules using a strong IR-laser pump and probe technique in combination with the coincidence measurement. The nuclear movement is tracked by analyzing the time-dependent kinetic energy release (KER) spectra. The involved dissociation states and pathways are assigned with the help of the semiclassical Landau-Zener surface hopping calculations. The real-time bond-breaking dynamics of the ${3}^{2}\phantom{\rule{0.16em}{0ex}}A{}^{\ensuremath{'}}$ coupling to other states are observed for the two-body dissociation channel and the three-body dissociation channel but with high KER. The three-body dissociation channel with low KER is assigned to the direct breaking process from the ${3}^{2}\phantom{\rule{0.16em}{0ex}}A{}^{\ensuremath{''}}$ state. The overall agreements between the experimental and theoretical results demonstrate that the time-resolved Coulomb-explosion imaging is a valuable way to monitor the bond breaking and structural evolution of complex molecules.