论文标题
运动方程式多级CC3的振荡器强度
Oscillator strengths in the framework of equation of motion multilevel CC3
论文作者
论文摘要
我们提出了在电子结构程序ET中使用封闭壳多级耦合群集单打（MLCC3）的封闭壳多层耦合群集单打的有效实现。轨道空间被分成用CC3处理的活性部分，并在理论的耦合群集单打和双打（CCSD）水平上计算出的不活动部分。渐近地，CC3贡献缩放为$ O（n_ \ text {v} n^3_ \ text {v} n^3_ 3_ \ text {o}）$ floating-point operations（flop），其中$ n_v $，其中$ n_v $是$ n_ \ n_ \ n_ \ n_ \ n_ virt and utive and utive and utive and utive and utive and utive atirual and utive atious {轨道分别。因此，CC3的贡献仅与完整的系统大小线性缩放，并且与CCSD的成本相比，可以忽略不计。我们通过计算偶氮苯的UV-VIS光谱和BETAINE 30的核心激发态，证明了我们实施的能力。
We present an efficient implementation of the equation of motion oscillator strengths for the closed-shell multilevel coupled cluster singles and doubles with perturbative triples method (MLCC3) in the electronic structure program eT. The orbital space is split into an active part treated with CC3 and an inactive part computed at the coupled cluster singles and doubles (CCSD) level of theory. Asymptotically, the CC3 contribution scales as $O(n_\text{V} n^3_\text{v} n^3_\text{o})$ floating-point operations (FLOP), where $n_V$ is the total number of virtual orbitals while $n_\text{v}$ and $n_\text{o}$ are the number of active virtual and occupied orbitals, respectively. The CC3 contribution, thus, only scales linearly with the full system size and can become negligible compared to the cost of CCSD. We demonstrate the capabilities of our implementation by calculating the UV-VIS spectrum of azobenzene and a core excited state of betaine 30 with more than 1000 molecular orbitals.
