论文标题
在扰动重新归一化方法中有效的激发和光谱
Efficient excitations and spectra within a perturbative renormalization approach
论文作者
论文摘要
我们提出了一种自洽的方法，用于计算迭代$ \ Mathcal {O} [o} [n^5] $计算时间的带电激发的相关准粒子谱。这是基于辅助二阶Green的功能方法[O. Backhouse \ textit {et al。}，JCTC（2020）]，其中通过系统地将自能源能力化的动力学效应在二阶扰动理论中的动力学效应构建来构建。从跨W4-11分子测试集的广泛基准测试，我们表明，与Benchmark值相比，由$ 2H1P $和1H2P $空间产生的有效动力分辨率的迭代重新归如此和有效动力分辨率的截断可以显着提高产生的电离电位和电子亲和力预测的质量。在此测试集中，所得的方法在精度上表现出优于EOM-CC2和ADC（2）中带电激发的量子化学方法的较高精度，而自谐度也消除了对基本均值场参考的依赖性。该方法还允许对整个准粒子光谱进行单次计算，该光谱应用于苯甲喹酮分子，并证明了由于相关物理学而导致的单粒子间隙的减少，并直接访问了dyson轨道的定位。
We present a self-consistent approach for computing the correlated quasiparticle spectrum of charged excitations in iterative $\mathcal{O}[N^5]$ computational time. This is based on the auxiliary second-order Green's function approach [O. Backhouse \textit{et al.}, JCTC (2020)], in which a self-consistent effective Hamiltonian is constructed by systematically renormalizing the dynamical effects of the self-energy at second-order perturbation theory. From extensive benchmarking across the W4-11 molecular test set, we show that the iterative renormalization and truncation of the effective dynamical resolution arising from the $2h1p$ and $1h2p$ spaces can substantially improve the quality of the resulting ionization potential and electron affinity predictions compared to benchmark values. The resulting method is shown to be superior in accuracy to similarly scaling quantum chemical methods for charged excitations in EOM-CC2 and ADC(2), across this test set, while the self-consistency also removes the dependence on the underlying mean-field reference. The approach also allows for single-shot computation of the entire quasiparticle spectrum, which is applied to the benzoquinone molecule and demonstrates the reduction in the single-particle gap due to the correlated physics, and gives direct access to the localization of the Dyson orbitals.
