Correlated electron-nuclear dynamics in above-threshold multiphoton ionization of asymmetric molecule.
Correlated electron-nuclear dynamics in above-threshold multiphoton ionization of asymmetric molecule.
复制标题
不对称分子阈值以上多光子电离中的相关电子-核动力学
DOI：
10.1038/srep42585
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发表时间：
2017-02-20
影响因子：
4.6
通讯作者：
Lu P
中科院分区：
文献类型：
--
作者：
Wang Z;Li M;Zhou Y;Lan P;Lu P
在激光与分子相互作用中，光子能量在分子子系统中的分配决定了许多光子诱导的化学和物理动力学。分子多光子电离产生的电子-核能量共享已被用来揭示电子和碎片的相关动力学。然而，大多数以前的研究集中在对称分子。本文通过求解一维含时薛定谔方程（TDSE），研究了HeH ~（2+）强场光电离过程中的电子-核能分。与对称分子相比，HeH ~（2+）的电子-核能谱（JES）在一定的能量范围内出现了异常的能量移动，而在较高和较低的能量范围内，这种能量移动消失.通过追踪束缚态波包的时间演化，我们发现这种能量移动是由与永久偶极子有关的Stark位移和强场中2 p σ和2sσ态耦合引起的Autler-Townes效应共同作用的结果。只有当斯塔克效应和奥特勒-汤斯效应同时起重要作用时，JES的能移才会出现在一定的核距离上。我们进一步证明，电子-核能量共享可以通过改变激光强度来控制不对称分子，为更复杂的分子提供了操纵光化学反应的替代方法。
The partition of the photon energy into the subsystems of molecules determines many photon-induced chemical and physical dynamics in laser-molecule interactions. The electron-nuclear energy sharing from multiphoton ionization of molecules has been used to uncover the correlated dynamics of the electron and fragments. However, most previous studies focus on symmetric molecules. Here we study the electron-nuclear energy sharing in strong-field photoionization of HeH2+by solving the one-dimensional time-dependent Schrödinger equation (TDSE). Compared with symmetric molecules, the joint electron-nuclear energy spectrum (JES) of HeH2+reveals an anomalous energy shift at certain nuclear energies, while it disappears at higher and lower nuclear energies. Through tracing the time evolution of the wavepacket of bound states, we identify that this energy shift originates from the joint effect of the Stark shift, associated with the permanent dipole, and the Autler-Townes effect due to the coupling of the 2pσand 2sσstates in strong fields. The energy shift in the JES appears at certain nuclear distances only when both Stark effect and Autler-Townes effect play important roles. We further demonstrate that the electron-nuclei energy sharing can be controlled by varying laser intensity for asymmetric molecules, providing alternative approaches to manipulate photochemical reactions for more complex molecules.