Balbi Alice, Skeidsvoll Andreas S, Koch Henrik
Scuola Normale Superiore, Piazza dei Cavalieri, 7, I-56126 Pisa, Italy.
Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
J Phys Chem A. 2023 Oct 19;127(41):8676-8684. doi: 10.1021/acs.jpca.3c03678. Epub 2023 Oct 9.
Time-dependent equation-of-motion coupled cluster (TD-EOM-CC) is used to simulate impulsive stimulated X-ray Raman scattering (ISXRS) of ultrashort laser pulses by neon, carbon monoxide, pyrrole, and -aminophenol. The TD-EOM-CC equations are expressed in the basis of field-free EOM-CC states, where the calculation of the core-excited states is simplified through the use of the core-valence separation (CVS) approximation. The transfer of electronic population from the ground state to the core- and valence-excited states is calculated for different numbers of included core- and valence-excited states, as well as for electric field pulses with different polarizations and carrier frequencies. The results indicate that Gaussian pulses can transfer significant electronic populations to the valence states through the Raman process. The sensitivity of this population transfer to the model parameters is analyzed. The time-dependent electronic density for -aminophenol is also showcased, supporting the interpretation that ISXRS involves localized core excitations and can be used to rapidly generate valence wavepackets.
含时运动方程耦合簇方法（TD-EOM-CC）用于模拟氖、一氧化碳、吡咯和对氨基苯酚对超短激光脉冲的脉冲受激X射线拉曼散射（ISXRS）。TD-EOM-CC方程在场自由EOM-CC态的基础上表示，其中通过使用芯价分离（CVS）近似简化了芯激发态的计算。针对不同数量的包含的芯激发态和价激发态，以及不同偏振和载波频率的电场脉冲，计算了电子布居从基态到芯激发态和价激发态的转移。结果表明，高斯脉冲可以通过拉曼过程将大量电子布居转移到价态。分析了这种布居转移对模型参数的敏感性。还展示了对氨基苯酚的含时电子密度，支持了ISXRS涉及局域芯激发且可用于快速生成价波包的解释。
