Iskandar W, Rescigno T N, Orel A E, Larsen K A, Severt T, Streeter Z L, Jochim B, Griffin B, Call D, Davis V, McCurdy C W, Lucchese R R, Williams J B, Ben-Itzhak I, Slaughter D S, Weber T
Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Chemical Engineering, University of California, Davis, California 95616, USA.
J Chem Phys. 2024 Jul 28;161(4). doi: 10.1063/5.0219029.
We applied reaction microscopy to elucidate fast non-adiabatic dissociation dynamics of deuterated water molecules after direct photo-double ionization at 61 eV with synchrotron radiation. For the very rare D+ + O+ + D breakup channel, the particle momenta, angular, and energy distributions of electrons and ions, measured in coincidence, reveal distinct electronic dication states and their dissociation pathways via spin-orbit coupling and charge transfer at crossings and seams on the potential energy surfaces. Notably, we could distinguish between direct and fast sequential dissociation scenarios. For the latter case, our measurements reveal the geometry and orientation of the deuterated water molecule with respect to the polarization vector that leads to this rare 3-body molecular breakup channel. Aided by multi-reference configuration-interaction calculations, the dissociation dynamics could be traced on the relevant potential energy surfaces and particularly their crossings and seams. This approach also unraveled the ultrafast time scales governing these processes.
我们应用反应显微镜来阐明氘代水分子在61电子伏特同步辐射直接光双电离后的快速非绝热解离动力学。对于极其罕见的D⁺ + O⁺ + D解离通道，同时测量的电子和离子的粒子动量、角度和能量分布揭示了不同的双电离态及其通过自旋 - 轨道耦合以及势能面上交叉点和接缝处的电荷转移的解离途径。值得注意的是，我们能够区分直接解离和快速连续解离的情况。对于后一种情况，我们的测量揭示了氘代水分子相对于极化矢量的几何形状和取向，正是这种取向导致了这种罕见的三体分子解离通道。借助多参考组态相互作用计算，可以在相关势能面上，特别是它们的交叉点和接缝处追踪解离动力学。这种方法还揭示了控制这些过程的超快时间尺度。
