Molecular bond stabilization in the strong-field dissociation of O2+
Molecular bond stabilization in the strong-field dissociation of O2+
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O2 强场解离中的分子键稳定
DOI：
10.1103/physreva.101.043410
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发表时间：
2020
影响因子：
2.9
通讯作者：
Thumm, U.
中科院分区：
文献类型：
--
作者：
Abanador, P. M.;Pauly, T.;Thumm, U.
我们从理论上研究了在当代泵浦探测实验中实现的条件下，分子离子暴露于强、短激光脉冲下的旋转和振动动力学。我们在玻恩-奥本海默近似下求解了随机排列分子离子初始分布的含时薛定谔方程。对于固定的峰值强度，我们的数值计算结果表明，总的角度integrateddissociation产率不单调增加，增加红外探测脉冲的持续时间。我们发现这种脉冲持续时间相关的稳定是一致的瞬态捕获的核概率密度在光诱导（键硬化）的势能面和强大的旋转激发。我们分析了这种稳定化效应及其潜在的键硬化机制（i）在时域中，通过以下的偶极耦合和阳离子态的部分核概率密度的演变，和（ii）在频域中，通过检查与这些状态相关的部分核概率密度的演变的振转量子拍谱。我们的分析揭示了键硬化机制的特征时间尺度，并解释了足够长的脉冲持续时间的键稳定的发病。
We theoretically examine the rotational and vibrational dynamics ofmolecular ions exposed to intense, short laser pulses for conditions realized in contemporary pump-probe experiments. We solve the time-dependent Schrödinger equation within the Born-Oppenheimer approximation for an initial distribution of randomly aligned molecular ions. For fixed peak intensities, our numerical results show that total, angle-integrateddissociation yields do not monotonically increase with increasing infrared-probe pulse duration. We find this pulse-duration-dependent stabilization to be consistent with the transient trapping of nuclear probability density in a light-induced (bond-hardening) potential-energy surface and robust against rotational excitation. We analyze this stabilization effect and its underlying bond-hardening mechanism (i) in the time domain, by following the evolution of partial nuclear probability densities associated with the dipole-coupledandcationic states, and (ii) in the frequency domain, by examining rovibrational quantum-beat spectra for the evolution of the partial nuclear probability densities associated with these states. Our analysis reveals the characteristic timescale for the bond-hardening mechanism inand explains the onset of bond stabilization for sufficiently long pulse durations.