论文标题
实时运动方程CC累积和CC Green的水和水二聚体光发射谱图
Real-time equation-of-motion CC cumulant and CC Green's function simulations of photoemission spectra of water and water dimer
论文作者
论文摘要
新开发的耦合群集（CC）方法可以在范围从核心结合到价值的各种能量尺度中对分子系统的电离电位和光谱函数进行模拟。本文讨论了通过实时运动方程CC累积方法（RT-EOM-CC）以及CC Green功能（CCGF）方法在水和水二聚体分子应用中获得的结果。我们比较了使用这些方法对价区域获得的电离电位与用CCSD（t）公式获得的结果作为N和N-1电子系统能量的差异。所有方法彼此均表现出良好的一致性。它们也与实验非常吻合，而电离电位的误差通常低于0.1 eV。我们还分析了与卫星峰位置相关的光谱函数的独特特征，该卫星峰位置是使用单个和双重激发的RT-EOM-CC和CCGF方法获得的，该方法是单体OH键长的函数，以及二聚体中的质子传递坐标。最后，我们分析了基集效应对计算电离电位质量的影响，并发现基集效应对于增强型集合而言不太明显。
Newly developed coupled-cluster (CC) methods enable simulations of ionization potentials and spectral functions of molecular systems in a wide range of energy scales ranging from core-binding to valence. This paper discusses results obtained with the real-time equation-of-motion CC cumulant approach (RT-EOM-CC), and CC Green's function (CCGF) approaches in applications to the water and water dimer molecules. We compare the ionization potentials obtained with these methods for the valence region with the results obtained with the CCSD(T) formulation as a difference of energies for N and N-1 electron systems. All methods show good agreement with each other. They also agree well with experiment, with errors usually below 0.1 eV for the ionization potentials. We also analyze unique features of the spectral functions, associated with the position of satellite peaks, obtained with the RT-EOM-CC and CCGF methods employing single and double excitations, as a function of the monomer OH bond length and the proton transfer coordinate in the dimer. Finally, we analyze the impact of the basis set effects on the quality of calculated ionization potentials and find that the basis set effects are less pronounced for the augmented-type sets.
