Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany.
J Phys Chem A. 2011 Apr 28;115(16):3755-65. doi: 10.1021/jp106355n. Epub 2010 Oct 13.
We present the extension of our field-induced surface hopping method for the description of the photoionization process and the simulation of time-resolved photoelectron spectra (TRPES). This is based on the combination of nonadiabatic molecular dynamics "on the fly" in the framework of TDDFT generalized for open shell systems under the influence of laser fields with the approximate quantum mechanical description of the photoionization process. Since arbitrary pulse shapes can be employed, this method can be also combined with the optimal control theory in order to steer the photoionization or to shape the outgoing electronic wavepackets. We illustrate our method for the simulation of TRPES on the prototype system of Ag(3), which involves excitation from the equilibrium triangular geometry, as well as excitation from the linear transition state, where in both cases nonadiabatic relaxation takes place in a complex manifold of electronic states. Our approach represents a generally applicable method for the prediction of time-resolved photoelectron spectra and their analysis in systems with complex electronic structure as well as many nuclear degrees freedom. This theoretical development should serve to stimulate new ultrafast experiments.
我们提出了一种扩展的场致表面跳跃方法，用于描述光致电离过程和模拟时间分辨光电子能谱（TRPES）。这是基于在激光场影响下，对开壳层体系进行时间域密度泛函理论（TDDFT）的非绝热分子动力学“实时”组合，以及对光致电离过程的近似量子力学描述。由于可以采用任意的脉冲形状，因此该方法还可以与最优控制理论相结合，以引导光致电离或塑造出射电子波包。我们以 Ag(3) 的原型系统为例，说明了我们用于模拟 TRPES 的方法，该系统涉及从平衡三角形几何结构的激发，以及从线性过渡态的激发，在这两种情况下，非绝热弛豫都发生在一个复杂的电子态流形中。我们的方法代表了一种普遍适用于预测具有复杂电子结构和多个核自由度的系统的时间分辨光电子能谱及其分析的方法。这一理论发展应该有助于激发新的超快实验。
