经典光解离动力学的玻尔量子化

Spectroscopic Signature of Chemical Bond Dissociation Revealed by Calculated Core-Electron Spectra

The advent of ultrashort soft x-ray pulse sources permits the use of established gas phase spectroscopy methods to investigate ultrafast photochemistry in isolated molecules with element and site specificity. In the present study, we simulate excited state wavepacket dynamics of a prototypical process, the ultrafast photodissociation of methyl iodide. Based on the simulation, we calculate time-dependent excited state carbon edge photoelectron and Auger electron spectra. We observe distinct signatures in both types of spectra and show their direct connection to C-I bond dissociation and charge …

Photo-accelerated water dissociation across one-atom-thick electrodes

Recent experiments demonstrated that interfacial water dissociation (H2O = H+ + OH-) could be accelerated exponentially by an electric field applied to graphene electrodes, a phenomenon related to the Wien effect. Here we report an order-of-magnitude acceleration of the interfacial water dissociation reaction under visible-light illumination. This process is accompanied by spatial separation of protons and hydroxide ions across one-atom-thick graphene and enhanced by strong interfacial electric fields. The found photo-effect is attributed to the combination of graphene's perfect selectivity wi…

绘制复杂光化学反应的完整反应路径

Mapping the Complete Reaction Path of a Complex Photochemical Reaction

我们探测的动力学解离CS $_2$分子在整个反应途径激发后。光电子能谱学测量使用实验室产生的飞秒极紫外脉冲监测竞争解离，内部转换，和系统间交叉动力学。解离发生在初始激发的单重态流形中，或者通过系间交叉发生在三重态流形中。两个产物通道进行监测，并显示，尽管更快，单重态解离是次要的产品和三重态产品占主导地位的最终产量。我们解释这一点的考虑单重态和三重态的准确的势能曲线。我们建议，快速的内部转换稳定的单重态人口动态，允许单重态-三重态弛豫通过系统间交叉和有效形成的自旋禁止的解离产物在较长的时间尺度上。该研究表明，测量完整的反应途径，以确定准确的反应机制的重要性。

乙烯电离后的解离与异构化：来自非绝热动力学模拟的见解

Dissociation and isomerization following ionization of ethylene: insights from non-adiabatic dynamics simulations

通过CASSCF非绝热动力学模拟，研究了乙烯阳离子四个最低激发态的解离与异构化机制，发现主要发生在基态，支持H2丢失源于亚乙基，但预测的异构化时间比实验推断更长。

β-TaON (100)/水界面水分解与质子动力学的分子层面见解

Molecular Insights into the Water Dissociation and Proton Dynamics at the $β$-TaON (100)/Water Interface

本研究通过从头算分子动力学模拟揭示β-TaON (100)/水界面因水自发解离和表面重构形成部分羟基化表面及强氢键网络，从而激活低势垒氢键等多种质子传输路径，显著提升界面质子跳跃速率，为TaON基半导体高光催化活性提供了分子层面的解释。

Exciton Dissociation and Charge Separation at Donor-Acceptor Interfaces from Quantum-Classical Dynamics Simulations

In organic photovoltaic (OPV) systems, exciton dissociation and ultrafast charge separation at donor-acceptor heterojunctions both play a key role in controlling the efficiency of the conversion of excitation energy into free charge carriers. In this work, nonadiabatic dynamics simulations based on the quantum-classical Liouville equation, are employed to study the real-time dynamics of exciton dissociation and charge separation at a model donor-acceptor interface. Benchmark comparisons for a variety of low dimensional donor-acceptor chain models are performed to assess the accuracy of the qua…

氨光解离动力学的共振多光子电离探测

Resonant multiphoton ionisation probe of the photodissociation dynamics of ammonia

在光电子能谱学实验中，用共振多光子电离探针研究了氨的$\tilde{A}$态的离解动力学。在多光子电离过程中使用共振中间体改变了电离倾向，当与等效的单光子电离实验相比时，允许进入不同的离子状态。通过$E'$ $^1$ A $_1'$里德伯中间体的电离意味着我们可以在很长一段时间内保持与离子态的重叠，从而使我们能够在几百飞秒内监测激发态的数量。光电子能谱中的振动态显示出两个不同的时间尺度，200 fs和320 fs，我们分别分配给非绝热和绝热解离过程。不同的时间尺度来自于两个解离路径的波包轨迹的差异，这两个解离路径共振激发中间里德堡态的不同振动态。时间尺度与从时间分辨离子动能释放测量获得的时间尺度相似，这表明我们可以测量到锥形交叉区域的不同轨迹。

多原子光解离的半经典统计动力学描述：态分辨分布

Semiclassical statistico-dynamical description of polyatomic photo-dissociations: State-resolved distributions

本文提出了一种研究间接多原子准经典轨道过程的新方法，该方法在提供振转分辨的同时，有效地避免了任何分级或加权过程。初始经典态以角度作用变量开始，以紧密匹配量子实验条件，然后按照最近发表的算法[J. Chem. Phys. 130，114103（2009）]转换为笛卡尔坐标。然后使用“关联”图传播轨迹，即在Hamilton和Brumer [J.Chem.Phys.82，595（1985）]的出口通道校正相空间理论的精神下的逆动力学模拟，这被证明是特别方便的。最后，提供了一个近似的准经典公式，在一般条件下，可以用来添加可能的旋转结构的振动分辨准经典分布。为了介绍该方法并说明其能力，研究了来自最近在308 nm处烯酮的光解离实验的相关平移能量分布[J. Chem. Phys. 124，014303（2006）]。一般来说，整体理论算法减少了要整合的轨迹总数，并允许对多原子实验进行完全理论预测。

强场效应在氢分子在银纳米壳上的光诱导解离中的影响

Strong-field effects in the photo-induced dissociation of the hydrogen molecule on a silver nanoshell

本研究探讨了强场效应在氢分子在银纳米壳上光诱导解离中的作用，揭示了多光子吸收和电离是解离机制。

CO$_{2}$里德堡态的超快动力学：自电离与解离寿命

Ultrafast Dynamics of the Rydberg States of CO$_{2}$: Autoionization and Dissociation Lifetimes

本研究利用阿秒XUV泵浦-探测光电子能谱测量了CO$_{2}$分子Henning锐线里德堡态的超快弛豫动力学，通过建模预解离与自电离的竞争，首次提取了n=4, 5, 6态的自电离和预解离寿命。

Mechanisms and dynamics of the NH$_2^{+}$ + H$^{+}$ and NH$^{+}$ + H$^{+}$ + H fragmentation channels upon single-photon double ionization of NH$_3$

We present state-selective measurements on the NH$_2^{+}$ + H$^{+}$ and NH$^{+}$ + H$^{+}$ + H dissociation channels following single-photon double ionization at 61.5 eV of neutral NH$_{3}$, where the two photoelectrons and two cations are measured in coincidence using 3-D momentum imaging. Three dication electronic states are identified to contribute to the NH$_2^{+}$ + H$^{+}$ dissociation channel, where the excitation in one of the three states undergoes intersystem crossing prior to dissociation, producing a cold NH$_2^+$ fragment. In contrast, the other two states directly dissociate, pro…