Severt Travis, Streeter Zachary L, Iskandar Wael, Larsen Kirk A, Gatton Averell, Trabert Daniel, Jochim Bethany, Griffin Brandon, Champenois Elio G, Brister Matthew M, Reedy Dylan, Call Demitri, Strom Richard, Landers Allen L, Dörner Reinhard, Williams Joshua B, Slaughter Daniel S, Lucchese Robert R, Weber Thorsten, McCurdy C William, Ben-Itzhak Itzik
J. R. Macdonald Laboratory, Physics Department, Kansas State University, Manhattan, KS, 66506, USA.
Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
Nat Commun. 2022 Sep 1;13(1):5146. doi: 10.1038/s41467-022-32836-6.
The double photoionization of a molecule by one photon ejects two electrons and typically creates an unstable dication. Observing the subsequent fragmentation products in coincidence can reveal a surprisingly detailed picture of the dynamics. Determining the time evolution and quantum mechanical states involved leads to deeper understanding of molecular dynamics. Here in a combined experimental and theoretical study, we unambiguously separate the sequential breakup via D + OD intermediates, from other processes leading to the same D + D + O final products of double ionization of water by a single photon. Moreover, we experimentally identify, separate, and follow step by step, two pathways involving the b Σ and a Δ electronic states of the intermediate OD ion. Our classical trajectory calculations on the relevant potential energy surfaces reproduce well the measured data and, combined with the experiment, enable the determination of the internal energy and angular momentum distribution of the OD intermediate.
一个光子对分子的双光电离会逐出两个电子，通常会产生一个不稳定的双阳离子。同时观测随后的碎片产物能够揭示出令人惊讶的详细动力学图景。确定所涉及的时间演化和量子力学状态有助于更深入地理解分子动力学。在这项结合了实验与理论的研究中，我们明确地将经由D + OD中间体的相继解离过程，与导致水单光子双电离产生相同D + D + O最终产物的其他过程区分开来。此外，我们通过实验识别、分离并逐步追踪了涉及中间体OD离子的b Σ和a Δ电子态的两条路径。我们在相关势能面上进行的经典轨迹计算很好地再现了测量数据，并与实验相结合，得以确定OD中间体的内能和角动量分布。
